Merge from trunk revision 104c05c5284b7822d770ee51a7d91946c7e56d50.

98 files changed, 5653 insertions, 3076 deletions

diff --git a/libphobos/ChangeLog b/libphobos/ChangeLog
index 235af5b..fa1aef7 100644
--- a/libphobos/ChangeLog
+++ b/libphobos/ChangeLog
@@ -1,3 +1,223 @@
+2021-09-01  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* m4/druntime/os.m4: Update comment for DRUNTIME_OS_SOURCES.
+
+2021-09-01  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* src/Makefile.am: Don't add zlib when ENABLE_LIBDRUNTIME_ONLY.
+	* src/Makefile.in: Regenerate.
+
+2021-08-30  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* configure: Regenerate.
+	* m4/autoconf.m4 (AC_LANG_PROGRAM): Declare module name 'object'.
+	* m4/gcc_support.m4 (WITH_LOCAL_DRUNTIME): Compile tests with
+	-fno-druntime.
+
+2021-06-11  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/100999
+	* src/MERGE: Merge upstream phobos 55bb17543.
+
+2021-05-14  Bernd Edlinger  <bernd.edlinger@hotmail.de>
+
+	* src/std/process.d (unittest): Remove tmpname on exit.
+	* src/MERGE: Merge upstream phobos 63f4caa90.
+
+2021-05-13  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/MERGE: Merge upstream druntime 98c6ff0c.
+
+2021-05-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* src/MERGE: Merge upstream phobos 32cfe9b61.
+
+2021-04-21  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/core/thread/osthread.d (callWithStackShell): Statically
+	generate PPC and PPC64 asm implementations, and conditionally remove
+	PPC register names on non-Darwin targets.
+
+2021-04-20  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/98584
+	* libdruntime/gcc/deh.d (scanLSDA): Update calls to read_uleb128 and
+	read_encoded_value.
+	(actionTableLookup): Update calls to read_sleb128 and
+	read_encoded_value_with_base.
+	* libdruntime/gcc/unwind/pe.d (read_uleb128): Update signature.
+	(read_sleb128): Update signature.
+	(read_unaligned): New function.
+	(read_encoded_value_with_base): Update signature.  Call read_unaligned
+	instead of unsafe pointer dereferencing.
+	(read_encoded_value): Update signature.
+
+2021-04-19  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/98494
+	* libdruntime/MERGE: Merge upstream druntime 89f870b7.
+	* src/MERGE: Merge upstream phobos e6907ff3e.
+
+2021-04-19  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/98058
+	* configure: Regenerate.
+	* libdruntime/Makefile.am (DRUNTIME_DSOURCES_DARWIN): Add
+	core/sys/darwin/config.d
+	* libdruntime/Makefile.in: Regenerate.
+	* libdruntime/config/powerpc/switchcontext.S: Implement
+	fiber_switchContext for __MACH__.
+	* libdruntime/config/x86/switchcontext.S: Likewise.
+	* libdruntime/core/sys/darwin/config.d: New file.
+	* libdruntime/core/thread/fiber.d (Fiber.getThis): Mark noinline.
+	(UnsafeFiberMigration): Define for OSX/X86 and OSX/X86_64.
+	* libdruntime/core/thread/osthread.d (callWithStackShell): Add inline
+	assembler implementation for X86, X86_64, PPC, and PPC64.
+	* libdruntime/core/thread/threadbase.d (ThreadBase.getThis): Mark
+	noinline.
+	* libdruntime/gcc/deh.d (FuncTable): Remove definition.
+	* m4/druntime/os.m4 (DRUNTIME_OS_MINFO_BRACKETING): Check for right
+	bracket symbol on darwin* targets.
+	* testsuite/libphobos.thread/fiber_guard_page.d: Update test to
+	support ucontext-based Fibers.
+
+2021-04-19  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/99794
+	* libdruntime/Makefile.am (DRUNTIME_SOURCES_CONFIGURED): Add
+	config/mingw/msvc.c on DRUNTIME_OS_MINGW.
+	* libdruntime/Makefile.in: Regenerate.
+	* libdruntime/config/mingw/msvc.c: New file.
+	* libdruntime/config/mingw/switchcontext.S (fiber_switchContext): Fix
+	function definition.
+	* libdruntime/gcc/deh.d (__gdc_personality_seh0): Fix call to
+	_GCC_specific_handler.
+	* libdruntime/gcc/gthread.d (__gthread_once_t): Fix definition.
+	* libdruntime/gcc/unwind/generic.d (_GCC_specific_handler): Fix
+	declaration.
+	* libdruntime/rt/dmain2.d (rt_loadLibrary): Remove function.
+	(rt_loadLibraryW): Remove function.
+	(initLibrary): Remove function.
+	(rt_unloadLibrary): Remove function.
+
+2021-04-19  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/99691
+	* configure: Regenerate.
+	* libdruntime/config/common/threadasm.S: Add __OpenBSD__.
+	* libdruntime/gcc/backtrace.d: Import core.sys.openbsd.dlfcn on
+	OpenBSD platforms.
+	* libdruntime/gcc/sections/elf.d (SharedElf): Define on OpenBSD.
+	(linkMapForHandle): Implement for OpenBSD.
+	(exeLinkMap): Remove.
+	(getDependencies): Adjust dlpi_addr on OpenBSD.
+	(handleForName): Implement for OpenBSD.
+	(IterateManually): Define on OpenBSD.
+	* libdruntime/gcc/sections/package.d (SectionsElf): Define on OpenBSD.
+	* m4/druntime/libraries.m4 (DRUNTIME_LIBRARIES_ATOMIC): Test for
+	enable_libatomic.
+	(DRUNTIME_LIBRARIES_BACKTRACE): Test for enable_libbacktrace.
+
+2021-04-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* Makefile.in: Regenerate.
+	* configure: Regenerate.
+	* configure.ac: Call DRUNTIME_SECTION_FLAGS.
+	* libdruntime/Makefile.am: Add SECTION_FLAGS to AM_DFLAGS.
+	* libdruntime/Makefile.in: Regenerate.
+	* m4/druntime.m4 (DRUNTIME_SECTION_FLAGS): New macro.
+	* src/Makefile.am: Add SECTION_FLAGS to AM_DFLAGS.
+	* src/Makefile.in: Regenerate.
+	* testsuite/Makefile.in: Regenerate.
+
+2021-04-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/Makefile.am (DRUNTIME_DSOURCES): Removed
+	gcc/sections/android.d, elf_shared.d, osx.d, win32.d, and win64.d.
+	Added gcc/sections/common.d, elf.d macho.d, and pecoff.d.
+	* libdruntime/Makefile.in: Regenerate.
+	* libdruntime/core/thread/osthread.d: Update externDFunc FQDN names to
+	use platform independant section function names.
+	* libdruntime/gcc/sections/elf_shared.d: Renamed to...
+	* libdruntime/gcc/sections/elf.d: ...this.  Mangle functions for
+	core.thread interface as if they come from the gcc.sections module.
+	* libdruntime/gcc/sections/package.d: Update public imports, declare
+	functions for core.thread interface.
+	* libdruntime/gcc/sections/android.d: Removed.
+	* libdruntime/gcc/sections/osx.d: Removed.
+	* libdruntime/gcc/sections/win32.d: Removed.
+	* libdruntime/gcc/sections/win64.d: Removed.
+	* libdruntime/gcc/sections/common.d: New file.
+	* libdruntime/gcc/sections/macho.d: New file.
+	* libdruntime/gcc/sections/pecoff.d: New file.
+
+2021-04-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* testsuite/libphobos.druntime/druntime.exp: Compile all tests with
+	-static-libphobos.
+	* testsuite/libphobos.phobos/phobos.exp: Likewise.
+
+2021-04-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* testsuite/libphobos.druntime/druntime.exp: Remove
+	is-effective-target static.
+	* testsuite/libphobos.phobos/phobos.exp: Likewise.
+
+2021-04-10  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	PR d/99812
+	* testsuite/libphobos.druntime_shared/druntime_shared.exp: Re-add
+	-fno-moduleinfo flag to dg-runtest.
+	* testsuite/libphobos.phobos_shared/phobos_shared.exp: Likewise.
+
+2021-04-08  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/Makefile.am (DRUNTIME_DSOURCES): Add
+	  gcc/attributes.d.
+	* libdruntime/Makefile.in: Regenerate.
+	* libdruntime/gcc/attribute.d: Deprecate module, publicly import
+	gcc.attributes.
+	* libdruntime/gcc/deh.d: Update imports.
+	* libdruntime/gcc/attributes.d: New file.
+
+2021-04-06  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/MERGE: Merge upstream druntime 1134b710.
+
+2021-04-03  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* libdruntime/MERGE: Merge upstream druntime 483bc129.
+	* libdruntime/Makefile.am (DRUNTIME_DSOURCES_DARWIN): Add
+	core/sys/darwin/fcntl.d.
+	(DRUNTIME_DSOURCES_OPENBSD): Add core/sys/openbsd/unistd.d.
+	(DRUNTIME_DSOURCES_WINDOWS): Add core/sys/windows/stdc/malloc.d.
+	* libdruntime/Makefile.in: Regenerate.
+	* src/MERGE: Merge upstream phobos f89dc217a.
+	* src/Makefile.am (PHOBOS_DSOURCES): Add std/regex/internal/tests2.d.
+	* src/Makefile.in: Regenerate.
+	* testsuite/libphobos.exceptions/chain.d: Fix format arguments.
+	* testsuite/libphobos.exceptions/line_trace.d: Likewise.
+
+2021-03-26  Iain Buclaw  <ibuclaw@gdcproject.org>
+
+	* Makefile.in: Regenerate.
+	* configure: Regenerate.
+	* configure.ac: Substitute enable_shared, enable_static, and
+	phobos_lt_pic_flag.
+	* libdruntime/Makefile.am (AM_DFLAGS): Replace
+	  phobos_compiler_pic_flag with phobos_lt_pic_flags, and
+	  phobos_compiler_shared_flag.
+	* libdruntime/Makefile.in: Regenerate.
+	* src/Makefile.am (AM_DFLAGS): Replace phobos_compiler_pic_flag
+	  with phobos_lt_pic_flag, and phobos_compiler_shared_flag.
+	* src/Makefile.in: Regenerate.
+	* testsuite/Makefile.in: Regenerate.
+	* testsuite/libphobos.druntime_shared/druntime_shared.exp: Remove
+	-fversion=Shared and -fno-moduleinfo from default extra test flags.
+	* testsuite/libphobos.phobos_shared/phobos_shared.exp: Likewise.
+	* testsuite/testsuite_flags.in: Add phobos_compiler_shared_flag to
+	--gdcflags.
+
 2021-02-04  Iain Buclaw  <ibuclaw@gdcproject.org>
 
 	PR d/98910
diff --git a/libphobos/Makefile.in b/libphobos/Makefile.in
index d422484..a8f7e16 100644
--- a/libphobos/Makefile.in
+++ b/libphobos/Makefile.in
@@ -271,6 +271,7 @@ PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
 RANLIB = @RANLIB@
+SECTION_FLAGS = @SECTION_FLAGS@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
 SHELL = @SHELL@
@@ -298,6 +299,8 @@ datadir = @datadir@
 datarootdir = @datarootdir@
 docdir = @docdir@
 dvidir = @dvidir@
+enable_shared = @enable_shared@
+enable_static = @enable_static@
 exec_prefix = @exec_prefix@
 gcc_version = @gcc_version@
 gdc_include_dir = @gdc_include_dir@
@@ -327,6 +330,7 @@ oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
 phobos_compiler_pic_flag = @phobos_compiler_pic_flag@
 phobos_compiler_shared_flag = @phobos_compiler_shared_flag@
+phobos_lt_pic_flag = @phobos_lt_pic_flag@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
diff --git a/libphobos/configure b/libphobos/configure
index c940a40..14298a0 100755
--- a/libphobos/configure
+++ b/libphobos/configure
@@ -700,11 +700,15 @@ DRUNTIME_CPU_ARM_FALSE
 DRUNTIME_CPU_ARM_TRUE
 DRUNTIME_CPU_AARCH64_FALSE
 DRUNTIME_CPU_AARCH64_TRUE
+SECTION_FLAGS
 libphobos_srcdir
 libphobos_builddir
 get_gcc_base_ver
 phobos_compiler_shared_flag
 phobos_compiler_pic_flag
+phobos_lt_pic_flag
+enable_static
+enable_shared
 OTOOL64
 OTOOL
 LIPO
@@ -5378,7 +5382,7 @@ fi
 
 
   gdc_save_DFLAGS=$GDCFLAGS
-  GDCFLAGS="-fno-moduleinfo -nostdinc -I $phobos_cv_abs_srcdir/libdruntime  $GDCFLAGS"
+  GDCFLAGS="-fno-druntime -nostdinc -I $phobos_cv_abs_srcdir/libdruntime  $GDCFLAGS"
 
   ac_ext=d
 ac_compile='$GDC -c $GDCFLAGS conftest.$ac_ext >&5'
@@ -5388,7 +5392,7 @@ ac_compiler_gnu=yes
     { $as_echo "$as_me:${as_lineno-$LINENO}: checking If $GDC can compile D sources" >&5
 $as_echo_n "checking If $GDC can compile D sources... " >&6; }
     cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
 
 
 extern(C) int main() {
@@ -11746,7 +11750,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11749 "configure"
+#line 11753 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -11852,7 +11856,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 11855 "configure"
+#line 11859 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -12093,7 +12097,7 @@ CC="$lt_save_CC"
 
 
   gdc_save_DFLAGS=$GDCFLAGS
-  GDCFLAGS="-fno-moduleinfo -nostdinc -I $phobos_cv_abs_srcdir/libdruntime  $GDCFLAGS"
+  GDCFLAGS="-fno-druntime -nostdinc -I $phobos_cv_abs_srcdir/libdruntime  $GDCFLAGS"
 
 
 # Source file extension for D test sources.
@@ -13997,8 +14001,14 @@ CFLAGS=$lt_save_CFLAGS
   GDCFLAGS=$gdc_save_DFLAGS
 
 
+
+
 # libtool variables for Phobos shared and position-independent compiles.
 #
+# Use phobos_lt_pic_flag to designate the automake variable
+# used to encapsulate the default libtool approach to creating objects
+# with position-independent code. Default: -prefer-pic.
+#
 # Use phobos_compiler_shared_flag to designate the compile-time flags for
 # creating shared objects. Default: -fversion=Shared.
 #
@@ -14010,26 +14020,23 @@ CFLAGS=$lt_save_CFLAGS
 # libtool, and so we make it here.  How it is handled is that in shared
 # compilations the `lt_prog_compiler_pic_D' variable is used to instead
 # ensure that conditional compilation of shared runtime code is compiled in.
-# The original PIC flags are then used in the compilation of every object.
-#
-# Why are objects destined for libgphobos.a compiled with -fPIC?
-# Because -fPIC is not harmful to use for objects destined for static
-# libraries. In addition, using -fPIC will allow the use of static
-# libgphobos.a in the creation of other D shared libraries.
 if test "$enable_shared" = yes; then
+  phobos_lt_pic_flag="-prefer-pic"
   phobos_compiler_pic_flag="$lt_prog_compiler_pic_D"
   phobos_compiler_shared_flag="-fversion=Shared"
 else
+  phobos_lt_pic_flag=
   phobos_compiler_pic_flag=
   phobos_compiler_shared_flag=
 fi
 
 
 
+
 # Override the libtool's pic_flag and pic_mode.
 # Do this step after AM_PROG_LIBTOOL, but before AC_OUTPUT.
 # NB: this impacts --with-pic and --without-pic.
-lt_prog_compiler_pic_D="$phobos_compiler_shared_flag"
+lt_prog_compiler_pic_D="$phobos_compiler_pic_flag $phobos_compiler_shared_flag"
 pic_mode='default'
 
 # Determine what GCC version number to use in filesystem paths.
@@ -14079,6 +14086,48 @@ fi
   fi
 
 
+
+
+  gdc_save_DFLAGS=$GDCFLAGS
+  GDCFLAGS="-fno-druntime -nostdinc -I $phobos_cv_abs_srcdir/libdruntime -nophoboslib $GDCFLAGS"
+
+    ac_ext=d
+ac_compile='$GDC -c $GDCFLAGS conftest.$ac_ext >&5'
+ac_link='$GDC -o conftest$ac_exeext $GDCFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=yes
+
+    GDCFLAGS="$GDCFLAGS -g -Werror -ffunction-sections -fdata-sections"
+    cat > conftest.$ac_ext <<_ACEOF
+module object;
+int foo; void bar() { }
+
+extern(C) int main() {
+  return 0;
+}
+_ACEOF
+if ac_fn_d_try_compile "$LINENO"; then :
+  ac_fdsections=yes
+else
+  ac_fdsections=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+    if test "x$ac_fdsections" = "xyes"; then
+      SECTION_FLAGS='-ffunction-sections -fdata-sections'
+    fi
+    { $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_fdsections" >&5
+$as_echo "$ac_fdsections" >&6; }
+    ac_ext=c
+ac_cpp='$CPP $CPPFLAGS'
+ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
+ac_link='$CC -o conftest$ac_exeext $CFLAGS $CPPFLAGS $LDFLAGS conftest.$ac_ext $LIBS >&5'
+ac_compiler_gnu=$ac_cv_c_compiler_gnu
+
+
+  GDCFLAGS=$gdc_save_DFLAGS
+
+
+
+
   druntime_target_cpu_parsed=""
   case "$target_cpu" in
       aarch64*)
@@ -14373,6 +14422,8 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
+
+
   ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'
 ac_compile='$CC -c $CFLAGS $CPPFLAGS conftest.$ac_ext >&5'
@@ -14381,17 +14432,29 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
   { $as_echo "$as_me:${as_lineno-$LINENO}: checking for minfo section bracketing" >&5
 $as_echo_n "checking for minfo section bracketing... " >&6; }
+  case "$druntime_cv_target_os" in
+      darwin*)
+	section="__DATA,__minfodata"
+	start="section\$start\$__DATA\$__minfodata"
+	stop="section\$end\$__DATA\$__minfodata"
+	;;
+      *)
+	section="minfo"
+	start="__start_minfo"
+	stop="__stop_minfo"
+	;;
+  esac
   cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
-    void* module_info_ptr __attribute__((section ("minfo")));
-    extern void* __start_minfo __attribute__((visibility ("hidden")));
-    extern void* __stop_minfo __attribute__((visibility ("hidden")));
+    void* module_info_ptr __attribute__((section ("$section")));
+    extern void* start_minfo __asm__("$start") __attribute__((visibility ("hidden")));
+    extern void* stop_minfo __asm__("$stop") __attribute__((visibility ("hidden")));
 
     int main()
     {
         // Never run, just to prevent compiler from optimizing access
-        return &__start_minfo == &__stop_minfo;
+        return (int)(&stop_minfo - &start_minfo);
     }
 
 _ACEOF
@@ -14499,7 +14562,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
   gdc_save_DFLAGS=$GDCFLAGS
-  GDCFLAGS="-fno-moduleinfo -nostdinc -I $phobos_cv_abs_srcdir/libdruntime -nophoboslib $GDCFLAGS"
+  GDCFLAGS="-fno-druntime -nostdinc -I $phobos_cv_abs_srcdir/libdruntime -nophoboslib $GDCFLAGS"
 
   ac_ext=d
 ac_compile='$GDC -c $GDCFLAGS conftest.$ac_ext >&5'
@@ -14513,7 +14576,7 @@ if ${ac_cv_search_malloc+:} false; then :
 else
   ac_func_search_save_LIBS=$LIBS
 cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
  extern(C) int malloc();
 
 extern(C) int main() {
@@ -14559,7 +14622,7 @@ if ${ac_cv_search_pthread_create+:} false; then :
 else
   ac_func_search_save_LIBS=$LIBS
 cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
  extern(C) int pthread_create();
 
 extern(C) int main() {
@@ -14605,7 +14668,7 @@ if ${ac_cv_search_cosf+:} false; then :
 else
   ac_func_search_save_LIBS=$LIBS
 cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
  extern(C) int cosf();
 
 extern(C) int main() {
@@ -14651,7 +14714,7 @@ if ${ac_cv_search_clock_gettime+:} false; then :
 else
   ac_func_search_save_LIBS=$LIBS
 cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
  extern(C) int clock_gettime();
 
 extern(C) int main() {
@@ -14702,7 +14765,7 @@ $as_echo_n "checking for atomic builtins for byte... " >&6; }
 else
 
     cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
 import gcc.builtins;
 
 extern(C) int main() {
@@ -14736,7 +14799,7 @@ $as_echo_n "checking for atomic builtins for short... " >&6; }
 else
 
     cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
 import gcc.builtins;
 
 extern(C) int main() {
@@ -14770,7 +14833,7 @@ $as_echo_n "checking for atomic builtins for int... " >&6; }
 else
 
     cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
 import gcc.builtins;
 
 extern(C) int main() {
@@ -14804,7 +14867,7 @@ $as_echo_n "checking for atomic builtins for long... " >&6; }
 else
 
     cat > conftest.$ac_ext <<_ACEOF
-module mod;
+module object;
 import gcc.builtins;
 
 extern(C) int main() {
@@ -14868,7 +14931,7 @@ fi
 
   DCFG_HAVE_LIBATOMIC=false
   LIBATOMIC=
-  if test "x$with_libatomic" != "xno"; then :
+  if test "x$enable_libatomic" != "xno" && test "x$with_libatomic" != "xno"; then :
 
     DCFG_HAVE_LIBATOMIC=true
     LIBATOMIC=../../libatomic/libatomic_convenience.la
@@ -14904,7 +14967,7 @@ if test "${with_libbacktrace+set}" = set; then :
 fi
 
 
-  if test "x$with_libbacktrace" != "xno"; then :
+  if test "x$enable_libbacktrace" != "xno" && test "x$with_libbacktrace" != "xno"; then :
 
     LIBBACKTRACE=../../libbacktrace/libbacktrace.la
 
diff --git a/libphobos/configure.ac b/libphobos/configure.ac
index cc9af29..3b5a830 100644
--- a/libphobos/configure.ac
+++ b/libphobos/configure.ac
@@ -91,9 +91,15 @@ AC_SUBST(CFLAGS_FOR_BUILD)
 LT_INIT(dlopen)
 AM_PROG_LIBTOOL
 WITH_LOCAL_DRUNTIME([LT_LANG([D])], [])
+AC_SUBST(enable_shared)
+AC_SUBST(enable_static)
 
 # libtool variables for Phobos shared and position-independent compiles.
 #
+# Use phobos_lt_pic_flag to designate the automake variable
+# used to encapsulate the default libtool approach to creating objects
+# with position-independent code. Default: -prefer-pic.
+#
 # Use phobos_compiler_shared_flag to designate the compile-time flags for
 # creating shared objects. Default: -fversion=Shared.
 #
@@ -105,26 +111,23 @@ WITH_LOCAL_DRUNTIME([LT_LANG([D])], [])
 # libtool, and so we make it here.  How it is handled is that in shared
 # compilations the `lt_prog_compiler_pic_D' variable is used to instead
 # ensure that conditional compilation of shared runtime code is compiled in.
-# The original PIC flags are then used in the compilation of every object.
-#
-# Why are objects destined for libgphobos.a compiled with -fPIC?
-# Because -fPIC is not harmful to use for objects destined for static
-# libraries. In addition, using -fPIC will allow the use of static
-# libgphobos.a in the creation of other D shared libraries.
 if test "$enable_shared" = yes; then
+  phobos_lt_pic_flag="-prefer-pic"
   phobos_compiler_pic_flag="$lt_prog_compiler_pic_D"
   phobos_compiler_shared_flag="-fversion=Shared"
 else
+  phobos_lt_pic_flag=
   phobos_compiler_pic_flag=
   phobos_compiler_shared_flag=
 fi
+AC_SUBST(phobos_lt_pic_flag)
 AC_SUBST(phobos_compiler_pic_flag)
 AC_SUBST(phobos_compiler_shared_flag)
 
 # Override the libtool's pic_flag and pic_mode.
 # Do this step after AM_PROG_LIBTOOL, but before AC_OUTPUT.
 # NB: this impacts --with-pic and --without-pic.
-lt_prog_compiler_pic_D="$phobos_compiler_shared_flag"
+lt_prog_compiler_pic_D="$phobos_compiler_pic_flag $phobos_compiler_shared_flag"
 pic_mode='default'
 
 # Determine what GCC version number to use in filesystem paths.
@@ -134,6 +137,7 @@ GCC_BASE_VER
 DRUNTIME_CONFIGURE
 DRUNTIME_MULTILIB
 DRUNTIME_WERROR
+DRUNTIME_SECTION_FLAGS
 DRUNTIME_CPU_SOURCES
 DRUNTIME_OS_SOURCES
 DRUNTIME_OS_THREAD_MODEL
diff --git a/libphobos/libdruntime/MERGE b/libphobos/libdruntime/MERGE
index a4a9a94..0d554e0 100644
--- a/libphobos/libdruntime/MERGE
+++ b/libphobos/libdruntime/MERGE
@@ -1,4 +1,4 @@
-0fd4364c4a4eb2ce0ebb8f613092c5bed7a63bf9
+98c6ff0cf1241a0cfac196bf8a0523b1d4ecd3ac
 
 The first line of this file holds the git revision number of the last
 merge done from the dlang/druntime repository.
diff --git a/libphobos/libdruntime/Makefile.am b/libphobos/libdruntime/Makefile.am
index 945271e..a2e2bff 100644
--- a/libphobos/libdruntime/Makefile.am
+++ b/libphobos/libdruntime/Makefile.am
@@ -23,8 +23,8 @@ D_EXTRA_DFLAGS=-nostdinc -I $(srcdir) -I .
 
 # D flags for compilation
 AM_DFLAGS= \
-	$(phobos_compiler_pic_flag) \
-	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(CET_DFLAGS)
+	$(phobos_lt_pic_flag) $(phobos_compiler_shared_flag) \
+	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(SECTION_FLAGS) $(CET_DFLAGS)
 
 # Flags for other kinds of sources
 AM_CFLAGS=$(CET_FLAGS)
@@ -69,7 +69,8 @@ if DRUNTIME_OS_LINUX
     DRUNTIME_SOURCES_CONFIGURED += $(DRUNTIME_DSOURCES_LINUX)
 endif
 if DRUNTIME_OS_MINGW
-    DRUNTIME_SOURCES_CONFIGURED += $(DRUNTIME_DSOURCES_WINDOWS)
+    DRUNTIME_SOURCES_CONFIGURED += $(DRUNTIME_DSOURCES_WINDOWS) \
+				   config/mingw/msvc.c
 endif
 if DRUNTIME_OS_SOLARIS
     DRUNTIME_SOURCES_CONFIGURED += $(DRUNTIME_DSOURCES_SOLARIS)
@@ -184,20 +185,19 @@ DRUNTIME_DSOURCES = core/atomic.d core/attribute.d core/bitop.d \
 	core/thread/threadbase.d core/thread/threadgroup.d core/thread/types.d \
 	core/time.d core/vararg.d core/volatile.d gc/bits.d gc/config.d \
 	gc/gcinterface.d gc/impl/conservative/gc.d gc/impl/manual/gc.d gc/os.d \
-	gc/pooltable.d gc/proxy.d gcc/attribute.d gcc/backtrace.d \
-	gcc/builtins.d gcc/deh.d gcc/emutls.d gcc/gthread.d \
-	gcc/sections/android.d gcc/sections/elf_shared.d gcc/sections/osx.d \
-	gcc/sections/package.d gcc/sections/win32.d gcc/sections/win64.d \
-	gcc/unwind/arm.d gcc/unwind/arm_common.d gcc/unwind/c6x.d \
-	gcc/unwind/generic.d gcc/unwind/package.d gcc/unwind/pe.d object.d \
-	rt/aApply.d rt/aApplyR.d rt/aaA.d rt/adi.d rt/arrayassign.d \
-	rt/arraycast.d rt/arraycat.d rt/cast_.d rt/config.d rt/critical_.d \
-	rt/deh.d rt/dmain2.d rt/invariant.d rt/lifetime.d rt/memory.d \
-	rt/minfo.d rt/monitor_.d rt/obj.d rt/qsort.d rt/sections.d \
-	rt/switch_.d rt/tlsgc.d rt/util/array.d rt/util/container/array.d \
-	rt/util/container/common.d rt/util/container/hashtab.d \
-	rt/util/container/treap.d rt/util/random.d rt/util/typeinfo.d \
-	rt/util/utf.d
+	gc/pooltable.d gc/proxy.d gcc/attribute.d gcc/attributes.d \
+	gcc/backtrace.d gcc/builtins.d gcc/deh.d gcc/emutls.d gcc/gthread.d \
+	gcc/sections/common.d gcc/sections/elf.d gcc/sections/macho.d \
+	gcc/sections/package.d gcc/sections/pecoff.d gcc/unwind/arm.d \
+	gcc/unwind/arm_common.d gcc/unwind/c6x.d gcc/unwind/generic.d \
+	gcc/unwind/package.d gcc/unwind/pe.d object.d rt/aApply.d rt/aApplyR.d \
+	rt/aaA.d rt/adi.d rt/arrayassign.d rt/arraycast.d rt/arraycat.d \
+	rt/cast_.d rt/config.d rt/critical_.d rt/deh.d rt/dmain2.d \
+	rt/invariant.d rt/lifetime.d rt/memory.d rt/minfo.d rt/monitor_.d \
+	rt/obj.d rt/qsort.d rt/sections.d rt/switch_.d rt/tlsgc.d \
+	rt/util/array.d rt/util/container/array.d rt/util/container/common.d \
+	rt/util/container/hashtab.d rt/util/container/treap.d rt/util/random.d \
+	rt/util/typeinfo.d rt/util/utf.d
 
 DRUNTIME_DSOURCES_STDCXX = core/stdcpp/exception.d \
 	core/stdcpp/typeinfo.d
@@ -206,9 +206,10 @@ DRUNTIME_DSOURCES_BIONIC = core/sys/bionic/err.d \
 	core/sys/bionic/fcntl.d core/sys/bionic/stdlib.d \
 	core/sys/bionic/string.d core/sys/bionic/unistd.d
 
-DRUNTIME_DSOURCES_DARWIN = core/sys/darwin/crt_externs.d \
-	core/sys/darwin/dlfcn.d core/sys/darwin/err.d \
-	core/sys/darwin/execinfo.d core/sys/darwin/ifaddrs.d \
+DRUNTIME_DSOURCES_DARWIN = core/sys/darwin/config.d \
+	core/sys/darwin/crt_externs.d core/sys/darwin/dlfcn.d \
+	core/sys/darwin/err.d core/sys/darwin/execinfo.d \
+	core/sys/darwin/fcntl.d core/sys/darwin/ifaddrs.d \
 	core/sys/darwin/mach/dyld.d core/sys/darwin/mach/getsect.d \
 	core/sys/darwin/mach/kern_return.d core/sys/darwin/mach/loader.d \
 	core/sys/darwin/mach/nlist.d core/sys/darwin/mach/port.d \
@@ -275,7 +276,8 @@ DRUNTIME_DSOURCES_OPENBSD = core/sys/openbsd/dlfcn.d \
 	core/sys/openbsd/sys/elf.d core/sys/openbsd/sys/elf32.d \
 	core/sys/openbsd/sys/elf64.d core/sys/openbsd/sys/elf_common.d \
 	core/sys/openbsd/sys/link_elf.d core/sys/openbsd/sys/mman.d \
-	core/sys/openbsd/sys/sysctl.d core/sys/openbsd/time.d
+	core/sys/openbsd/sys/sysctl.d core/sys/openbsd/time.d \
+	core/sys/openbsd/unistd.d
 
 DRUNTIME_DSOURCES_POSIX = core/sys/posix/aio.d \
 	core/sys/posix/arpa/inet.d core/sys/posix/config.d \
@@ -382,22 +384,22 @@ DRUNTIME_DSOURCES_WINDOWS = core/sys/windows/accctrl.d \
 	core/sys/windows/sqlext.d core/sys/windows/sqltypes.d \
 	core/sys/windows/sqlucode.d core/sys/windows/sspi.d \
 	core/sys/windows/stacktrace.d core/sys/windows/stat.d \
-	core/sys/windows/stdc/time.d core/sys/windows/subauth.d \
-	core/sys/windows/threadaux.d core/sys/windows/tlhelp32.d \
-	core/sys/windows/tmschema.d core/sys/windows/unknwn.d \
-	core/sys/windows/uuid.d core/sys/windows/vfw.d \
-	core/sys/windows/w32api.d core/sys/windows/winbase.d \
-	core/sys/windows/winber.d core/sys/windows/wincon.d \
-	core/sys/windows/wincrypt.d core/sys/windows/windef.d \
-	core/sys/windows/windows.d core/sys/windows/winerror.d \
-	core/sys/windows/wingdi.d core/sys/windows/winhttp.d \
-	core/sys/windows/wininet.d core/sys/windows/winioctl.d \
-	core/sys/windows/winldap.d core/sys/windows/winnetwk.d \
-	core/sys/windows/winnls.d core/sys/windows/winnt.d \
-	core/sys/windows/winperf.d core/sys/windows/winreg.d \
-	core/sys/windows/winsock2.d core/sys/windows/winspool.d \
-	core/sys/windows/winsvc.d core/sys/windows/winuser.d \
-	core/sys/windows/winver.d core/sys/windows/wtsapi32.d \
-	core/sys/windows/wtypes.d
+	core/sys/windows/stdc/malloc.d core/sys/windows/stdc/time.d \
+	core/sys/windows/subauth.d core/sys/windows/threadaux.d \
+	core/sys/windows/tlhelp32.d core/sys/windows/tmschema.d \
+	core/sys/windows/unknwn.d core/sys/windows/uuid.d \
+	core/sys/windows/vfw.d core/sys/windows/w32api.d \
+	core/sys/windows/winbase.d core/sys/windows/winber.d \
+	core/sys/windows/wincon.d core/sys/windows/wincrypt.d \
+	core/sys/windows/windef.d core/sys/windows/windows.d \
+	core/sys/windows/winerror.d core/sys/windows/wingdi.d \
+	core/sys/windows/winhttp.d core/sys/windows/wininet.d \
+	core/sys/windows/winioctl.d core/sys/windows/winldap.d \
+	core/sys/windows/winnetwk.d core/sys/windows/winnls.d \
+	core/sys/windows/winnt.d core/sys/windows/winperf.d \
+	core/sys/windows/winreg.d core/sys/windows/winsock2.d \
+	core/sys/windows/winspool.d core/sys/windows/winsvc.d \
+	core/sys/windows/winuser.d core/sys/windows/winver.d \
+	core/sys/windows/wtsapi32.d core/sys/windows/wtypes.d
 
 DRUNTIME_DISOURCES = __entrypoint.di __main.di
diff --git a/libphobos/libdruntime/Makefile.in b/libphobos/libdruntime/Makefile.in
index 06c0296..cb2e372 100644
--- a/libphobos/libdruntime/Makefile.in
+++ b/libphobos/libdruntime/Makefile.in
@@ -117,7 +117,9 @@ target_triplet = @target@
 @DRUNTIME_OS_NETBSD_TRUE@am__append_6 = $(DRUNTIME_DSOURCES_NETBSD)
 @DRUNTIME_OS_OPENBSD_TRUE@am__append_7 = $(DRUNTIME_DSOURCES_OPENBSD)
 @DRUNTIME_OS_LINUX_TRUE@am__append_8 = $(DRUNTIME_DSOURCES_LINUX)
-@DRUNTIME_OS_MINGW_TRUE@am__append_9 = $(DRUNTIME_DSOURCES_WINDOWS)
+@DRUNTIME_OS_MINGW_TRUE@am__append_9 = $(DRUNTIME_DSOURCES_WINDOWS) \
+@DRUNTIME_OS_MINGW_TRUE@				   config/mingw/msvc.c
+
 @DRUNTIME_OS_SOLARIS_TRUE@am__append_10 = $(DRUNTIME_DSOURCES_SOLARIS)
 # CPU specific sources
 @DRUNTIME_CPU_AARCH64_TRUE@am__append_11 = config/aarch64/switchcontext.S
@@ -209,11 +211,11 @@ am__objects_1 = core/atomic.lo core/attribute.lo core/bitop.lo \
 	core/thread/types.lo core/time.lo core/vararg.lo \
 	core/volatile.lo gc/bits.lo gc/config.lo gc/gcinterface.lo \
 	gc/impl/conservative/gc.lo gc/impl/manual/gc.lo gc/os.lo \
-	gc/pooltable.lo gc/proxy.lo gcc/attribute.lo gcc/backtrace.lo \
-	gcc/builtins.lo gcc/deh.lo gcc/emutls.lo gcc/gthread.lo \
-	gcc/sections/android.lo gcc/sections/elf_shared.lo \
-	gcc/sections/osx.lo gcc/sections/package.lo \
-	gcc/sections/win32.lo gcc/sections/win64.lo gcc/unwind/arm.lo \
+	gc/pooltable.lo gc/proxy.lo gcc/attribute.lo gcc/attributes.lo \
+	gcc/backtrace.lo gcc/builtins.lo gcc/deh.lo gcc/emutls.lo \
+	gcc/gthread.lo gcc/sections/common.lo gcc/sections/elf.lo \
+	gcc/sections/macho.lo gcc/sections/package.lo \
+	gcc/sections/pecoff.lo gcc/unwind/arm.lo \
 	gcc/unwind/arm_common.lo gcc/unwind/c6x.lo \
 	gcc/unwind/generic.lo gcc/unwind/package.lo gcc/unwind/pe.lo \
 	object.lo rt/aApply.lo rt/aApplyR.lo rt/aaA.lo rt/adi.lo \
@@ -254,9 +256,10 @@ am__objects_3 = core/sys/posix/aio.lo core/sys/posix/arpa/inet.lo \
 	core/sys/posix/time.lo core/sys/posix/ucontext.lo \
 	core/sys/posix/unistd.lo core/sys/posix/utime.lo
 @DRUNTIME_OS_POSIX_TRUE@am__objects_4 = $(am__objects_3)
-am__objects_5 = core/sys/darwin/crt_externs.lo \
-	core/sys/darwin/dlfcn.lo core/sys/darwin/err.lo \
-	core/sys/darwin/execinfo.lo core/sys/darwin/ifaddrs.lo \
+am__objects_5 = core/sys/darwin/config.lo \
+	core/sys/darwin/crt_externs.lo core/sys/darwin/dlfcn.lo \
+	core/sys/darwin/err.lo core/sys/darwin/execinfo.lo \
+	core/sys/darwin/fcntl.lo core/sys/darwin/ifaddrs.lo \
 	core/sys/darwin/mach/dyld.lo core/sys/darwin/mach/getsect.lo \
 	core/sys/darwin/mach/kern_return.lo \
 	core/sys/darwin/mach/loader.lo core/sys/darwin/mach/nlist.lo \
@@ -322,7 +325,8 @@ am__objects_15 = core/sys/openbsd/dlfcn.lo core/sys/openbsd/err.lo \
 	core/sys/openbsd/sys/elf32.lo core/sys/openbsd/sys/elf64.lo \
 	core/sys/openbsd/sys/elf_common.lo \
 	core/sys/openbsd/sys/link_elf.lo core/sys/openbsd/sys/mman.lo \
-	core/sys/openbsd/sys/sysctl.lo core/sys/openbsd/time.lo
+	core/sys/openbsd/sys/sysctl.lo core/sys/openbsd/time.lo \
+	core/sys/openbsd/unistd.lo
 @DRUNTIME_OS_OPENBSD_TRUE@am__objects_16 = $(am__objects_15)
 am__objects_17 = core/sys/linux/config.lo core/sys/linux/dlfcn.lo \
 	core/sys/linux/elf.lo core/sys/linux/epoll.lo \
@@ -408,24 +412,26 @@ am__objects_19 = core/sys/windows/accctrl.lo \
 	core/sys/windows/sql.lo core/sys/windows/sqlext.lo \
 	core/sys/windows/sqltypes.lo core/sys/windows/sqlucode.lo \
 	core/sys/windows/sspi.lo core/sys/windows/stacktrace.lo \
-	core/sys/windows/stat.lo core/sys/windows/stdc/time.lo \
-	core/sys/windows/subauth.lo core/sys/windows/threadaux.lo \
-	core/sys/windows/tlhelp32.lo core/sys/windows/tmschema.lo \
-	core/sys/windows/unknwn.lo core/sys/windows/uuid.lo \
-	core/sys/windows/vfw.lo core/sys/windows/w32api.lo \
-	core/sys/windows/winbase.lo core/sys/windows/winber.lo \
-	core/sys/windows/wincon.lo core/sys/windows/wincrypt.lo \
-	core/sys/windows/windef.lo core/sys/windows/windows.lo \
-	core/sys/windows/winerror.lo core/sys/windows/wingdi.lo \
-	core/sys/windows/winhttp.lo core/sys/windows/wininet.lo \
-	core/sys/windows/winioctl.lo core/sys/windows/winldap.lo \
-	core/sys/windows/winnetwk.lo core/sys/windows/winnls.lo \
-	core/sys/windows/winnt.lo core/sys/windows/winperf.lo \
-	core/sys/windows/winreg.lo core/sys/windows/winsock2.lo \
-	core/sys/windows/winspool.lo core/sys/windows/winsvc.lo \
-	core/sys/windows/winuser.lo core/sys/windows/winver.lo \
-	core/sys/windows/wtsapi32.lo core/sys/windows/wtypes.lo
-@DRUNTIME_OS_MINGW_TRUE@am__objects_20 = $(am__objects_19)
+	core/sys/windows/stat.lo core/sys/windows/stdc/malloc.lo \
+	core/sys/windows/stdc/time.lo core/sys/windows/subauth.lo \
+	core/sys/windows/threadaux.lo core/sys/windows/tlhelp32.lo \
+	core/sys/windows/tmschema.lo core/sys/windows/unknwn.lo \
+	core/sys/windows/uuid.lo core/sys/windows/vfw.lo \
+	core/sys/windows/w32api.lo core/sys/windows/winbase.lo \
+	core/sys/windows/winber.lo core/sys/windows/wincon.lo \
+	core/sys/windows/wincrypt.lo core/sys/windows/windef.lo \
+	core/sys/windows/windows.lo core/sys/windows/winerror.lo \
+	core/sys/windows/wingdi.lo core/sys/windows/winhttp.lo \
+	core/sys/windows/wininet.lo core/sys/windows/winioctl.lo \
+	core/sys/windows/winldap.lo core/sys/windows/winnetwk.lo \
+	core/sys/windows/winnls.lo core/sys/windows/winnt.lo \
+	core/sys/windows/winperf.lo core/sys/windows/winreg.lo \
+	core/sys/windows/winsock2.lo core/sys/windows/winspool.lo \
+	core/sys/windows/winsvc.lo core/sys/windows/winuser.lo \
+	core/sys/windows/winver.lo core/sys/windows/wtsapi32.lo \
+	core/sys/windows/wtypes.lo
+@DRUNTIME_OS_MINGW_TRUE@am__objects_20 = $(am__objects_19) \
+@DRUNTIME_OS_MINGW_TRUE@	config/mingw/libgdruntime_la-msvc.lo
 am__objects_21 = core/sys/solaris/dlfcn.lo core/sys/solaris/elf.lo \
 	core/sys/solaris/err.lo core/sys/solaris/execinfo.lo \
 	core/sys/solaris/libelf.lo core/sys/solaris/link.lo \
@@ -460,24 +466,26 @@ am_libgdruntime_la_OBJECTS = $(am__objects_33)
 libgdruntime_la_OBJECTS = $(am_libgdruntime_la_OBJECTS)
 am__DEPENDENCIES_2 = $(am__DEPENDENCIES_1) $(am__DEPENDENCIES_1)
 am__objects_34 = core/stdc/libgdruntime_convenience_la-errno_.lo
-@DRUNTIME_CPU_AARCH64_TRUE@am__objects_35 = config/aarch64/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_ARM_TRUE@am__objects_36 = config/arm/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_MIPS_TRUE@am__objects_37 = config/mips/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_POWERPC_TRUE@am__objects_38 = config/powerpc/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_X86_TRUE@@DRUNTIME_OS_MINGW_TRUE@am__objects_39 = config/mingw/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_X86_TRUE@@DRUNTIME_OS_MINGW_FALSE@am__objects_40 = config/x86/libgdruntime_convenience_la-switchcontext.lo
-@DRUNTIME_CPU_SYSTEMZ_TRUE@am__objects_41 = config/systemz/libgdruntime_convenience_la-get_tls_offset.lo
-@DRUNTIME_CPU_S390_TRUE@am__objects_42 = config/s390/libgdruntime_convenience_la-get_tls_offset.lo
-am__objects_43 = $(am__objects_4) $(am__objects_6) $(am__objects_8) \
+@DRUNTIME_OS_MINGW_TRUE@am__objects_35 = $(am__objects_19) \
+@DRUNTIME_OS_MINGW_TRUE@	config/mingw/libgdruntime_convenience_la-msvc.lo
+@DRUNTIME_CPU_AARCH64_TRUE@am__objects_36 = config/aarch64/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_ARM_TRUE@am__objects_37 = config/arm/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_MIPS_TRUE@am__objects_38 = config/mips/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_POWERPC_TRUE@am__objects_39 = config/powerpc/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_X86_TRUE@@DRUNTIME_OS_MINGW_TRUE@am__objects_40 = config/mingw/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_X86_TRUE@@DRUNTIME_OS_MINGW_FALSE@am__objects_41 = config/x86/libgdruntime_convenience_la-switchcontext.lo
+@DRUNTIME_CPU_SYSTEMZ_TRUE@am__objects_42 = config/systemz/libgdruntime_convenience_la-get_tls_offset.lo
+@DRUNTIME_CPU_S390_TRUE@am__objects_43 = config/s390/libgdruntime_convenience_la-get_tls_offset.lo
+am__objects_44 = $(am__objects_4) $(am__objects_6) $(am__objects_8) \
 	$(am__objects_10) $(am__objects_12) $(am__objects_14) \
-	$(am__objects_16) $(am__objects_18) $(am__objects_20) \
-	$(am__objects_22) $(am__objects_35) $(am__objects_36) \
-	$(am__objects_37) $(am__objects_38) $(am__objects_39) \
-	$(am__objects_40) $(am__objects_41) $(am__objects_42)
-am__objects_44 = $(am__objects_1) $(am__objects_34) $(am__objects_43) \
+	$(am__objects_16) $(am__objects_18) $(am__objects_35) \
+	$(am__objects_22) $(am__objects_36) $(am__objects_37) \
+	$(am__objects_38) $(am__objects_39) $(am__objects_40) \
+	$(am__objects_41) $(am__objects_42) $(am__objects_43)
+am__objects_45 = $(am__objects_1) $(am__objects_34) $(am__objects_44) \
 	$(am__objects_32)
-am__objects_45 = $(am__objects_44)
-am_libgdruntime_convenience_la_OBJECTS = $(am__objects_45)
+am__objects_46 = $(am__objects_45)
+am_libgdruntime_convenience_la_OBJECTS = $(am__objects_46)
 libgdruntime_convenience_la_OBJECTS =  \
 	$(am_libgdruntime_convenience_la_OBJECTS)
 AM_V_P = $(am__v_P_@AM_V@)
@@ -632,6 +640,7 @@ PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
 RANLIB = @RANLIB@
+SECTION_FLAGS = @SECTION_FLAGS@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
 SHELL = @SHELL@
@@ -659,6 +668,8 @@ datadir = @datadir@
 datarootdir = @datarootdir@
 docdir = @docdir@
 dvidir = @dvidir@
+enable_shared = @enable_shared@
+enable_static = @enable_static@
 exec_prefix = @exec_prefix@
 gcc_version = @gcc_version@
 gdc_include_dir = @gdc_include_dir@
@@ -688,6 +699,7 @@ oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
 phobos_compiler_pic_flag = @phobos_compiler_pic_flag@
 phobos_compiler_shared_flag = @phobos_compiler_shared_flag@
+phobos_lt_pic_flag = @phobos_lt_pic_flag@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
@@ -720,8 +732,8 @@ D_EXTRA_DFLAGS = -nostdinc -I $(srcdir) -I .
 
 # D flags for compilation
 AM_DFLAGS = \
-	$(phobos_compiler_pic_flag) \
-	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(CET_DFLAGS)
+	$(phobos_lt_pic_flag) $(phobos_compiler_shared_flag) \
+	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(SECTION_FLAGS) $(CET_DFLAGS)
 
 
 # Flags for other kinds of sources
@@ -810,20 +822,19 @@ DRUNTIME_DSOURCES = core/atomic.d core/attribute.d core/bitop.d \
 	core/thread/threadbase.d core/thread/threadgroup.d core/thread/types.d \
 	core/time.d core/vararg.d core/volatile.d gc/bits.d gc/config.d \
 	gc/gcinterface.d gc/impl/conservative/gc.d gc/impl/manual/gc.d gc/os.d \
-	gc/pooltable.d gc/proxy.d gcc/attribute.d gcc/backtrace.d \
-	gcc/builtins.d gcc/deh.d gcc/emutls.d gcc/gthread.d \
-	gcc/sections/android.d gcc/sections/elf_shared.d gcc/sections/osx.d \
-	gcc/sections/package.d gcc/sections/win32.d gcc/sections/win64.d \
-	gcc/unwind/arm.d gcc/unwind/arm_common.d gcc/unwind/c6x.d \
-	gcc/unwind/generic.d gcc/unwind/package.d gcc/unwind/pe.d object.d \
-	rt/aApply.d rt/aApplyR.d rt/aaA.d rt/adi.d rt/arrayassign.d \
-	rt/arraycast.d rt/arraycat.d rt/cast_.d rt/config.d rt/critical_.d \
-	rt/deh.d rt/dmain2.d rt/invariant.d rt/lifetime.d rt/memory.d \
-	rt/minfo.d rt/monitor_.d rt/obj.d rt/qsort.d rt/sections.d \
-	rt/switch_.d rt/tlsgc.d rt/util/array.d rt/util/container/array.d \
-	rt/util/container/common.d rt/util/container/hashtab.d \
-	rt/util/container/treap.d rt/util/random.d rt/util/typeinfo.d \
-	rt/util/utf.d
+	gc/pooltable.d gc/proxy.d gcc/attribute.d gcc/attributes.d \
+	gcc/backtrace.d gcc/builtins.d gcc/deh.d gcc/emutls.d gcc/gthread.d \
+	gcc/sections/common.d gcc/sections/elf.d gcc/sections/macho.d \
+	gcc/sections/package.d gcc/sections/pecoff.d gcc/unwind/arm.d \
+	gcc/unwind/arm_common.d gcc/unwind/c6x.d gcc/unwind/generic.d \
+	gcc/unwind/package.d gcc/unwind/pe.d object.d rt/aApply.d rt/aApplyR.d \
+	rt/aaA.d rt/adi.d rt/arrayassign.d rt/arraycast.d rt/arraycat.d \
+	rt/cast_.d rt/config.d rt/critical_.d rt/deh.d rt/dmain2.d \
+	rt/invariant.d rt/lifetime.d rt/memory.d rt/minfo.d rt/monitor_.d \
+	rt/obj.d rt/qsort.d rt/sections.d rt/switch_.d rt/tlsgc.d \
+	rt/util/array.d rt/util/container/array.d rt/util/container/common.d \
+	rt/util/container/hashtab.d rt/util/container/treap.d rt/util/random.d \
+	rt/util/typeinfo.d rt/util/utf.d
 
 DRUNTIME_DSOURCES_STDCXX = core/stdcpp/exception.d \
 	core/stdcpp/typeinfo.d
@@ -832,9 +843,10 @@ DRUNTIME_DSOURCES_BIONIC = core/sys/bionic/err.d \
 	core/sys/bionic/fcntl.d core/sys/bionic/stdlib.d \
 	core/sys/bionic/string.d core/sys/bionic/unistd.d
 
-DRUNTIME_DSOURCES_DARWIN = core/sys/darwin/crt_externs.d \
-	core/sys/darwin/dlfcn.d core/sys/darwin/err.d \
-	core/sys/darwin/execinfo.d core/sys/darwin/ifaddrs.d \
+DRUNTIME_DSOURCES_DARWIN = core/sys/darwin/config.d \
+	core/sys/darwin/crt_externs.d core/sys/darwin/dlfcn.d \
+	core/sys/darwin/err.d core/sys/darwin/execinfo.d \
+	core/sys/darwin/fcntl.d core/sys/darwin/ifaddrs.d \
 	core/sys/darwin/mach/dyld.d core/sys/darwin/mach/getsect.d \
 	core/sys/darwin/mach/kern_return.d core/sys/darwin/mach/loader.d \
 	core/sys/darwin/mach/nlist.d core/sys/darwin/mach/port.d \
@@ -901,7 +913,8 @@ DRUNTIME_DSOURCES_OPENBSD = core/sys/openbsd/dlfcn.d \
 	core/sys/openbsd/sys/elf.d core/sys/openbsd/sys/elf32.d \
 	core/sys/openbsd/sys/elf64.d core/sys/openbsd/sys/elf_common.d \
 	core/sys/openbsd/sys/link_elf.d core/sys/openbsd/sys/mman.d \
-	core/sys/openbsd/sys/sysctl.d core/sys/openbsd/time.d
+	core/sys/openbsd/sys/sysctl.d core/sys/openbsd/time.d \
+	core/sys/openbsd/unistd.d
 
 DRUNTIME_DSOURCES_POSIX = core/sys/posix/aio.d \
 	core/sys/posix/arpa/inet.d core/sys/posix/config.d \
@@ -1008,23 +1021,23 @@ DRUNTIME_DSOURCES_WINDOWS = core/sys/windows/accctrl.d \
 	core/sys/windows/sqlext.d core/sys/windows/sqltypes.d \
 	core/sys/windows/sqlucode.d core/sys/windows/sspi.d \
 	core/sys/windows/stacktrace.d core/sys/windows/stat.d \
-	core/sys/windows/stdc/time.d core/sys/windows/subauth.d \
-	core/sys/windows/threadaux.d core/sys/windows/tlhelp32.d \
-	core/sys/windows/tmschema.d core/sys/windows/unknwn.d \
-	core/sys/windows/uuid.d core/sys/windows/vfw.d \
-	core/sys/windows/w32api.d core/sys/windows/winbase.d \
-	core/sys/windows/winber.d core/sys/windows/wincon.d \
-	core/sys/windows/wincrypt.d core/sys/windows/windef.d \
-	core/sys/windows/windows.d core/sys/windows/winerror.d \
-	core/sys/windows/wingdi.d core/sys/windows/winhttp.d \
-	core/sys/windows/wininet.d core/sys/windows/winioctl.d \
-	core/sys/windows/winldap.d core/sys/windows/winnetwk.d \
-	core/sys/windows/winnls.d core/sys/windows/winnt.d \
-	core/sys/windows/winperf.d core/sys/windows/winreg.d \
-	core/sys/windows/winsock2.d core/sys/windows/winspool.d \
-	core/sys/windows/winsvc.d core/sys/windows/winuser.d \
-	core/sys/windows/winver.d core/sys/windows/wtsapi32.d \
-	core/sys/windows/wtypes.d
+	core/sys/windows/stdc/malloc.d core/sys/windows/stdc/time.d \
+	core/sys/windows/subauth.d core/sys/windows/threadaux.d \
+	core/sys/windows/tlhelp32.d core/sys/windows/tmschema.d \
+	core/sys/windows/unknwn.d core/sys/windows/uuid.d \
+	core/sys/windows/vfw.d core/sys/windows/w32api.d \
+	core/sys/windows/winbase.d core/sys/windows/winber.d \
+	core/sys/windows/wincon.d core/sys/windows/wincrypt.d \
+	core/sys/windows/windef.d core/sys/windows/windows.d \
+	core/sys/windows/winerror.d core/sys/windows/wingdi.d \
+	core/sys/windows/winhttp.d core/sys/windows/wininet.d \
+	core/sys/windows/winioctl.d core/sys/windows/winldap.d \
+	core/sys/windows/winnetwk.d core/sys/windows/winnls.d \
+	core/sys/windows/winnt.d core/sys/windows/winperf.d \
+	core/sys/windows/winreg.d core/sys/windows/winsock2.d \
+	core/sys/windows/winspool.d core/sys/windows/winsvc.d \
+	core/sys/windows/winuser.d core/sys/windows/winver.d \
+	core/sys/windows/wtsapi32.d core/sys/windows/wtypes.d
 
 DRUNTIME_DISOURCES = __entrypoint.di __main.di
 all: all-am
@@ -1201,6 +1214,7 @@ gcc/$(am__dirstamp):
 	@$(MKDIR_P) gcc
 	@: > gcc/$(am__dirstamp)
 gcc/attribute.lo: gcc/$(am__dirstamp)
+gcc/attributes.lo: gcc/$(am__dirstamp)
 gcc/backtrace.lo: gcc/$(am__dirstamp)
 gcc/builtins.lo: gcc/$(am__dirstamp)
 gcc/deh.lo: gcc/$(am__dirstamp)
@@ -1209,12 +1223,11 @@ gcc/gthread.lo: gcc/$(am__dirstamp)
 gcc/sections/$(am__dirstamp):
 	@$(MKDIR_P) gcc/sections
 	@: > gcc/sections/$(am__dirstamp)
-gcc/sections/android.lo: gcc/sections/$(am__dirstamp)
-gcc/sections/elf_shared.lo: gcc/sections/$(am__dirstamp)
-gcc/sections/osx.lo: gcc/sections/$(am__dirstamp)
+gcc/sections/common.lo: gcc/sections/$(am__dirstamp)
+gcc/sections/elf.lo: gcc/sections/$(am__dirstamp)
+gcc/sections/macho.lo: gcc/sections/$(am__dirstamp)
 gcc/sections/package.lo: gcc/sections/$(am__dirstamp)
-gcc/sections/win32.lo: gcc/sections/$(am__dirstamp)
-gcc/sections/win64.lo: gcc/sections/$(am__dirstamp)
+gcc/sections/pecoff.lo: gcc/sections/$(am__dirstamp)
 gcc/unwind/$(am__dirstamp):
 	@$(MKDIR_P) gcc/unwind
 	@: > gcc/unwind/$(am__dirstamp)
@@ -1339,10 +1352,12 @@ core/sys/posix/utime.lo: core/sys/posix/$(am__dirstamp)
 core/sys/darwin/$(am__dirstamp):
 	@$(MKDIR_P) core/sys/darwin
 	@: > core/sys/darwin/$(am__dirstamp)
+core/sys/darwin/config.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/crt_externs.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/dlfcn.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/err.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/execinfo.lo: core/sys/darwin/$(am__dirstamp)
+core/sys/darwin/fcntl.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/ifaddrs.lo: core/sys/darwin/$(am__dirstamp)
 core/sys/darwin/mach/$(am__dirstamp):
 	@$(MKDIR_P) core/sys/darwin/mach
@@ -1507,6 +1522,7 @@ core/sys/openbsd/sys/link_elf.lo:  \
 core/sys/openbsd/sys/mman.lo: core/sys/openbsd/sys/$(am__dirstamp)
 core/sys/openbsd/sys/sysctl.lo: core/sys/openbsd/sys/$(am__dirstamp)
 core/sys/openbsd/time.lo: core/sys/openbsd/$(am__dirstamp)
+core/sys/openbsd/unistd.lo: core/sys/openbsd/$(am__dirstamp)
 core/sys/linux/$(am__dirstamp):
 	@$(MKDIR_P) core/sys/linux
 	@: > core/sys/linux/$(am__dirstamp)
@@ -1687,6 +1703,8 @@ core/sys/windows/stat.lo: core/sys/windows/$(am__dirstamp)
 core/sys/windows/stdc/$(am__dirstamp):
 	@$(MKDIR_P) core/sys/windows/stdc
 	@: > core/sys/windows/stdc/$(am__dirstamp)
+core/sys/windows/stdc/malloc.lo:  \
+	core/sys/windows/stdc/$(am__dirstamp)
 core/sys/windows/stdc/time.lo: core/sys/windows/stdc/$(am__dirstamp)
 core/sys/windows/subauth.lo: core/sys/windows/$(am__dirstamp)
 core/sys/windows/threadaux.lo: core/sys/windows/$(am__dirstamp)
@@ -1720,6 +1738,10 @@ core/sys/windows/winuser.lo: core/sys/windows/$(am__dirstamp)
 core/sys/windows/winver.lo: core/sys/windows/$(am__dirstamp)
 core/sys/windows/wtsapi32.lo: core/sys/windows/$(am__dirstamp)
 core/sys/windows/wtypes.lo: core/sys/windows/$(am__dirstamp)
+config/mingw/$(am__dirstamp):
+	@$(MKDIR_P) config/mingw
+	@: > config/mingw/$(am__dirstamp)
+config/mingw/libgdruntime_la-msvc.lo: config/mingw/$(am__dirstamp)
 core/sys/solaris/$(am__dirstamp):
 	@$(MKDIR_P) core/sys/solaris
 	@: > core/sys/solaris/$(am__dirstamp)
@@ -1769,9 +1791,6 @@ config/powerpc/$(am__dirstamp):
 	@: > config/powerpc/$(am__dirstamp)
 config/powerpc/libgdruntime_la-switchcontext.lo:  \
 	config/powerpc/$(am__dirstamp)
-config/mingw/$(am__dirstamp):
-	@$(MKDIR_P) config/mingw
-	@: > config/mingw/$(am__dirstamp)
 config/mingw/libgdruntime_la-switchcontext.lo:  \
 	config/mingw/$(am__dirstamp)
 config/x86/$(am__dirstamp):
@@ -1796,6 +1815,8 @@ libgdruntime.la: $(libgdruntime_la_OBJECTS) $(libgdruntime_la_DEPENDENCIES) $(EX
 	$(AM_V_GEN)$(libgdruntime_la_LINK) -rpath $(toolexeclibdir) $(libgdruntime_la_OBJECTS) $(libgdruntime_la_LIBADD) $(LIBS)
 core/stdc/libgdruntime_convenience_la-errno_.lo:  \
 	core/stdc/$(am__dirstamp)
+config/mingw/libgdruntime_convenience_la-msvc.lo:  \
+	config/mingw/$(am__dirstamp)
 config/aarch64/libgdruntime_convenience_la-switchcontext.lo:  \
 	config/aarch64/$(am__dirstamp)
 config/arm/libgdruntime_convenience_la-switchcontext.lo:  \
@@ -1991,9 +2012,15 @@ config/s390/libgdruntime_convenience_la-get_tls_offset.lo: config/s390/get_tls_o
 core/stdc/libgdruntime_la-errno_.lo: core/stdc/errno_.c
 	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(libgdruntime_la_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o core/stdc/libgdruntime_la-errno_.lo `test -f 'core/stdc/errno_.c' || echo '$(srcdir)/'`core/stdc/errno_.c
 
+config/mingw/libgdruntime_la-msvc.lo: config/mingw/msvc.c
+	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(libgdruntime_la_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o config/mingw/libgdruntime_la-msvc.lo `test -f 'config/mingw/msvc.c' || echo '$(srcdir)/'`config/mingw/msvc.c
+
 core/stdc/libgdruntime_convenience_la-errno_.lo: core/stdc/errno_.c
 	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(libgdruntime_convenience_la_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o core/stdc/libgdruntime_convenience_la-errno_.lo `test -f 'core/stdc/errno_.c' || echo '$(srcdir)/'`core/stdc/errno_.c
 
+config/mingw/libgdruntime_convenience_la-msvc.lo: config/mingw/msvc.c
+	$(AM_V_CC)$(LIBTOOL) $(AM_V_lt) --tag=CC $(libgdruntime_convenience_la_LIBTOOLFLAGS) $(LIBTOOLFLAGS) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o config/mingw/libgdruntime_convenience_la-msvc.lo `test -f 'config/mingw/msvc.c' || echo '$(srcdir)/'`config/mingw/msvc.c
+
 mostlyclean-libtool:
 	-rm -f *.lo
 
diff --git a/libphobos/libdruntime/config/common/threadasm.S b/libphobos/libdruntime/config/common/threadasm.S
index 1e9bc76..3546217 100644
--- a/libphobos/libdruntime/config/common/threadasm.S
+++ b/libphobos/libdruntime/config/common/threadasm.S
@@ -22,7 +22,7 @@ a copy of the GCC Runtime Library Exception along with this program;
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */
 
-#if (__linux__ || __FreeBSD__ || __NetBSD__ || __DragonFly__) && __ELF__
+#if (__linux__ || __FreeBSD__ || __NetBSD__ || __OpenBSD__ || __DragonFly__) && __ELF__
 /*
  * Mark the resulting object file as not requiring execution permissions on
  * stack memory. The absence of this section would mark the whole resulting
diff --git a/libphobos/libdruntime/config/mingw/msvc.c b/libphobos/libdruntime/config/mingw/msvc.c
new file mode 100644
index 0000000..da40718
--- /dev/null
+++ b/libphobos/libdruntime/config/mingw/msvc.c
@@ -0,0 +1,169 @@
+/* Windows support code to wrap differences between different
+   versions of the Microsoft C libaries.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+<http://www.gnu.org/licenses/>.  */
+
+#ifdef __MINGW32__
+#include <_mingw.h>
+#endif
+#include <stdio.h>
+
+/* The D runtime library defines stdin, stdout, and stderr as extern(C) symbols
+   in the core.stdc.stdio module, and require initializing at start-up.  */
+__attribute__((weakref ("stdin")))
+static FILE *core_stdc_stdin;
+
+__attribute__((weakref ("stdout")))
+static FILE *core_stdc_stdout;
+
+__attribute__((weakref ("stderr")))
+static FILE *core_stdc_stderr;
+
+/* Set to 1 if runtime is using libucrt.dll.  */
+unsigned char msvcUsesUCRT;
+
+void
+init_msvc (void)
+{
+  core_stdc_stdin = stdin;
+  core_stdc_stdout = stdout;
+  core_stdc_stderr = stderr;
+
+#if __MSVCRT_VERSION__ >= 0xE00
+  msvcUsedUCRT = 1;
+#endif
+}
+
+/* Phobos std.stdio module assumes these functions are present at link time,
+   and not absent or macros.  */
+#ifdef _fgetc_nolock
+#undef _fgetc_nolock
+
+int
+_fgetc_nolock (FILE *fp)
+{
+  fp->_cnt--;
+  if (fp->_cnt >= 0)
+    {
+      const int c = *fp->_ptr;
+      fp->_ptr++;
+      return c & 0xff;
+    }
+  else
+    return _filbuf (fp);
+}
+
+#endif /* _fgetc_nolock */
+
+#ifdef _fputc_nolock
+#undef _fputc_nolock
+
+int
+_fputc_nolock (int c, FILE *fp)
+{
+  fp->_cnt--;
+  if (fp->_cnt >= 0)
+    {
+      *fp->_ptr = (char) c;
+      fp->_ptr++;
+      return c & 0xff;
+    }
+  else
+    return _flsbuf (c, fp);
+}
+
+#endif /* _fputc_nolock */
+
+#ifdef rewind
+#undef rewind
+
+void
+rewind (FILE *fp)
+{
+  fseek (fp, 0, SEEK_SET);
+  fp->_flag &= ~_IOERR;
+}
+
+#endif /* rewind */
+
+#ifdef clearerr
+#undef clearerr
+
+void
+clearerr (FILE *fp)
+{
+  fp->_flag &= ~(_IOERR | _IOEOF);
+}
+
+#endif /* clearerr */
+
+#ifdef feof
+#undef feof
+
+int
+feof (FILE *fp)
+{
+  return fp->_flag & _IOEOF;
+}
+
+#endif /* feof */
+
+#ifdef ferror
+#undef ferror
+
+int
+ferror (FILE *fp)
+{
+  return fp->_flag & _IOERR;
+}
+
+#endif /* ferror */
+
+#ifdef fileno
+#undef fileno
+
+int
+fileno (FILE *fp)
+{
+  return fp->_file;
+}
+
+#endif /* fileno */
+
+/* Phobos std.stdio module has a dependency on the UCRT library, so provide
+   stubs that forward to the nearest equivalent.  */
+#if __MSVCRT_VERSION__ < 0x800
+
+wint_t
+_fgetwc_nolock (FILE *fp)
+{
+  return fgetwc (fp);
+}
+
+wint_t
+_fputwc_nolock (wchar_t c, FILE *fp)
+{
+    return fputwc(c, fp);
+}
+
+#endif /* __MSVCRT_VERSION__ < 0x800*/
diff --git a/libphobos/libdruntime/config/mingw/switchcontext.S b/libphobos/libdruntime/config/mingw/switchcontext.S
index 6592ff6..0cb8b01 100644
--- a/libphobos/libdruntime/config/mingw/switchcontext.S
+++ b/libphobos/libdruntime/config/mingw/switchcontext.S
@@ -28,7 +28,10 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 
     .text
     .globl CSYM(fiber_switchContext)
-    .type CSYM(fiber_switchContext), @function
+    .def CSYM(fiber_switchContext)
+    .scl 2
+    .type 32
+    .endef
     .align 16
 CSYM(fiber_switchContext):
     .cfi_startproc
@@ -63,13 +66,15 @@ CSYM(fiber_switchContext):
     popq %RCX;
     jmp *%RCX;
     .cfi_endproc
-    .size CSYM(fiber_switchContext),.-CSYM(fiber_switchContext)
 
 #elif defined(_X86_)
 
     .text
     .globl CSYM(fiber_switchContext)
-    .type CSYM(fiber_switchContext), @function
+    .def CSYM(fiber_switchContext)
+    .scl 2
+    .type 32
+    .endef
     .align 16
 CSYM(fiber_switchContext):
     .cfi_startproc
@@ -104,6 +109,5 @@ CSYM(fiber_switchContext):
     // 'return' to complete switch
     ret;
     .cfi_endproc
-    .size CSYM(fiber_switchContext),.-CSYM(fiber_switchContext)
 
 #endif
diff --git a/libphobos/libdruntime/config/powerpc/switchcontext.S b/libphobos/libdruntime/config/powerpc/switchcontext.S
index d4ea577..74395b0 100644
--- a/libphobos/libdruntime/config/powerpc/switchcontext.S
+++ b/libphobos/libdruntime/config/powerpc/switchcontext.S
@@ -24,7 +24,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 
 #include "../common/threadasm.S"
 
-#if !defined(__PPC64__)
+#if !defined(__PPC64__) && !defined(__MACH__)
 
 /**
  * Performs a context switch.
@@ -151,4 +151,278 @@ CSYM(fiber_switchContext):
     .cfi_endproc
     .size CSYM(fiber_switchContext),.-CSYM(fiber_switchContext)
 
-#endif /* !defined(__PPC64__) */
+#elif defined(__MACH__)
+
+/* Implementation for Darwin/macOS preserving callee-saved regs.
+
+   FIXME : There is no unwind frame.
+   FIXME : not sure if we should save the vsave reg (perhaps using the slot we have
+           r11 in at present).  */
+
+/* Darwin has a red zone (220 bytes for PPC 288 for PPC64) which we can write
+   to before the stack is updated without worrying about it being clobbered by
+   signals or hardware interrupts.
+
+   The stack will be 16byte aligned on entry with:
+						  PPC	PPC64
+   SP-> +---------------------------------------+
+	| back chain to caller			| 0	  0
+	+---------------------------------------+
+	| slot to save CR			| 4       8
+	+---------------------------------------+
+	| slot to save LR			| 8       16
+	+---------------------------------------+
+	| etc.. etc.. as per C calling conv.    |  */
+
+# if __PPC64__
+#  define LD ld
+#  define ST std
+#  define STU stdu
+#  define SZ 8
+#  define MACHINE ppc64
+#  define RED_ZONE 288
+# else
+#  define LD lwz
+#  define ST stw
+#  define STU stwu
+#  define SZ 4
+#  define MACHINE ppc7400
+#  define RED_ZONE 220
+# endif
+
+# define SAVE_VECTORS 0
+/**
+ * Performs a context switch.
+ *
+ * r3 - old context pointer
+ * r4 - new context pointer
+ *
+ */
+    .machine MACHINE
+    .text
+    .globl CSYM(fiber_switchContext)
+    .align 2
+CSYM(fiber_switchContext):
+LFB0:
+    /* Get the link reg. */
+    mflr  r0
+    /* Get the callee-saved crs (well all of them, actually). */
+    mfcr  r12
+
+    /* Save GPRs, we save the static chain here too although it is not clear if we need to.  */
+    ST    r31, ( -1 * SZ)(r1)
+    ST    r30, ( -2 * SZ)(r1)
+    ST    r29, ( -3 * SZ)(r1)
+    ST    r28, ( -4 * SZ)(r1)
+    ST    r27, ( -5 * SZ)(r1)
+    ST    r26, ( -6 * SZ)(r1)
+    ST    r25, ( -7 * SZ)(r1)
+    ST    r24, ( -8 * SZ)(r1)
+    ST    r23, ( -9 * SZ)(r1)
+    ST    r22, (-10 * SZ)(r1)
+    ST    r21, (-11 * SZ)(r1)
+    ST    r20, (-12 * SZ)(r1)
+    ST    r19, (-13 * SZ)(r1)
+    ST    r18, (-14 * SZ)(r1)
+    ST    r17, (-15 * SZ)(r1)
+    ST    r16, (-16 * SZ)(r1)
+    ST    r15, (-17 * SZ)(r1)
+    ST    r14, (-18 * SZ)(r1)
+    ST    r13, (-19 * SZ)(r1)
+
+    /* Save the lr and cr into the normal function linkage area.  */
+    ST    r0, 2*SZ(r1)
+    ST    r12, SZ(r1)
+
+    /* We update the stack pointer here, since we do not want the GC to
+       scan the floating point registers. We are still 16-byte aligned. */
+    STU   r11, (-20 * SZ)(r1)
+
+    /* Update the stack pointer in the old context as per comment above. */
+    ST    r1, 0(r3)
+
+    /* Save FPRs - same for PPC and PPC64 */
+    stfd  f14, (-18 * 8)(r1)
+    stfd  f15, (-17 * 8)(r1)
+    stfd  f16, (-16 * 8)(r1)
+    stfd  f17, (-15 * 8)(r1)
+    stfd  f18, (-14 * 8)(r1)
+    stfd  f19, (-13 * 8)(r1)
+    stfd  f20, (-12 * 8)(r1)
+    stfd  f21, (-11 * 8)(r1)
+    stfd  f22, (-10 * 8)(r1)
+    stfd  f23, ( -9 * 8)(r1)
+    stfd  f24, ( -8 * 8)(r1)
+    stfd  f25, ( -7 * 8)(r1)
+    stfd  f26, ( -6 * 8)(r1)
+    stfd  f27, ( -5 * 8)(r1)
+    stfd  f28, ( -4 * 8)(r1)
+    stfd  f29, ( -3 * 8)(r1)
+    stfd  f30, ( -2 * 8)(r1)
+    stfd  f31, ( -1 * 8)(r1)
+
+#if SAVE_VECTORS
+    /* We are still 16byte aligned - so we are ok for vector saves.
+       but the combined size of the vectors (12 x 16) + the FPRs (144) exceeds the
+       red zone size so we need to adjust the stack again - note this means careful
+       ordering is needed on the restore.  */
+
+    addi  r1, r1, -(12*16+18*8)
+    li    r11, 0
+    stvx  v20,r11,r1
+    addi  r11, r11, 16
+    stvx  v21,r11,r1
+    addi  r11, r11, 16
+    stvx  v22,r11,r1
+    addi  r11, r11, 16
+    stvx  v23,r11,r1
+    addi  r11, r11, 16
+    stvx  v24,r11,r1
+    addi  r11, r11, 16
+    stvx  v25,r11,r1
+    addi  r11, r11, 16
+    stvx  v26,r11,r1
+    addi  r11, r11, 16
+    stvx  v27,r11,r1
+    addi  r11, r11, 16
+    stvx  v28,r11,r1
+    addi  r11, r11, 16
+    stvx  v29,r11,r1
+    addi  r11, r11, 16
+    stvx  v30,r11,r1
+    addi  r11, r11, 16
+    stvx  v31,r11,r1
+
+    /* Now do the same thing in reverse - starting with r4 pointing to
+       the block of GPRs - stage 1 point to the saved vectors and fprs. */
+
+    addi  r1, r4, -(12*16+18*8)
+    li    r11, 0
+    lvx   v20,r11,r1
+    addi  r11, r11, 16
+    lvx   v21,r11,r1
+    addi  r11, r11, 16
+    lvx   v22,r11,r1
+    addi  r11, r11, 16
+    lvx   v23,r11,r1
+    addi  r11, r11, 16
+    lvx   v24,r11,r1
+    addi  r11, r11, 16
+    lvx   v25,r11,r1
+    addi  r11, r11, 16
+    lvx   v26,r11,r1
+    addi  r11, r11, 16
+    lvx   v27,r11,r1
+    addi  r11, r11, 16
+    lvx   v28,r11,r1
+    addi  r11, r11, 16
+    lvx   v29,r11,r1
+    addi  r11, r11, 16
+    lvx   v30,r11,r1
+    addi  r11, r11, 16
+    lvx   v31,r11,r1
+#endif
+
+    /* Now it is safe to update the stack pointer since the combined
+       size of the GPRs and FPRs will not exceed the red zone.  */
+
+    addi  r1, r4, 20 * SZ
+
+    /* Restore FPRs */
+    lfd  f14, (-18 * 8)(r4)
+    lfd  f15, (-17 * 8)(r4)
+    lfd  f16, (-16 * 8)(r4)
+    lfd  f17, (-15 * 8)(r4)
+    lfd  f18, (-14 * 8)(r4)
+    lfd  f19, (-13 * 8)(r4)
+    lfd  f20, (-12 * 8)(r4)
+    lfd  f21, (-11 * 8)(r4)
+    lfd  f22, (-10 * 8)(r4)
+    lfd  f23, ( -9 * 8)(r4)
+    lfd  f24, ( -8 * 8)(r4)
+    lfd  f25, ( -7 * 8)(r4)
+    lfd  f26, ( -6 * 8)(r4)
+    lfd  f27, ( -5 * 8)(r4)
+    lfd  f28, ( -4 * 8)(r4)
+    lfd  f29, ( -3 * 8)(r4)
+    lfd  f30, ( -2 * 8)(r4)
+    lfd  f31, ( -1 * 8)(r4)
+
+    /* Pick up lr and cr */
+    LD    r0, 2*SZ(r1)
+    LD    r12, SZ(r1)
+
+    /* Restore GPRs */
+    LD     r11, (-20 * SZ)(r1)
+    LD     r13, (-19 * SZ)(r1)
+    LD     r14, (-18 * SZ)(r1)
+    LD     r15, (-17 * SZ)(r1)
+    LD     r16, (-16 * SZ)(r1)
+    LD     r17, (-15 * SZ)(r1)
+    LD     r18, (-14 * SZ)(r1)
+    LD     r19, (-13 * SZ)(r1)
+    LD     r20, (-12 * SZ)(r1)
+    LD     r21, (-11 * SZ)(r1)
+    LD     r22, (-10 * SZ)(r1)
+    LD     r23, ( -9 * SZ)(r1)
+    LD     r24, ( -8 * SZ)(r1)
+    LD     r25, ( -7 * SZ)(r1)
+    LD     r26, ( -6 * SZ)(r1)
+    LD     r27, ( -5 * SZ)(r1)
+    LD     r28, ( -4 * SZ)(r1)
+    LD     r29, ( -3 * SZ)(r1)
+    LD     r30, ( -2 * SZ)(r1)
+    LD     r31, ( -1 * SZ)(r1)
+
+    /* Set cr and lr */
+    mtcr  r12
+    mtlr  r0
+
+    /* Return and switch context */
+    blr
+LFE0:
+
+/* Minimal CFI / FDE which does not describe the stacking of the GPRs - but only that
+   the routine has been entered/exited.  */
+
+# if __PPC64__
+#  define DATA_ALIGN 0x78
+#  define ALIGN_SIZE 3
+#  define ADDRD .quad
+# else
+#  define DATA_ALIGN 0x7c
+#  define ALIGN_SIZE 3
+#  define ADDRD .long
+# endif
+
+	.section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
+EH_frame1:
+	.set L$set$0,LECIE1-LSCIE1
+	.long L$set$0	; Length of Common Information Entry
+LSCIE1:
+	.long	0	; CIE Identifier Tag
+	.byte	0x3	; CIE Version
+	.ascii "zR\0"	; CIE Augmentation
+	.byte	0x1	; uleb128 0x1; CIE Code Alignment Factor
+	.byte	DATA_ALIGN	; sleb128 -4/-8; CIE Data Alignment Factor
+	.byte	0x41	; uleb128 0x41; CIE RA Column
+	.byte	0x1	; uleb128 0x1; Augmentation size
+	.byte	0x10	; FDE Encoding (pcrel)
+	.byte	0xc	; DW_CFA_def_cfa
+	.byte	0x1	; uleb128 0x1
+	.byte	0	; uleb128 0
+	.p2align ALIGN_SIZE,0
+LECIE1:
+LSFDE1:
+	.set L$set$1,LEFDE1-LASFDE1
+	.long L$set$1	; FDE Length
+LASFDE1:
+	.long	LASFDE1-EH_frame1	; FDE CIE offset
+	ADDRD	LFB0-.	; FDE initial location
+	.set L$set$2,LFE0-LFB0
+	ADDRD L$set$2	; FDE address range
+	.byte	0	; uleb128 0; Augmentation size
+	.p2align ALIGN_SIZE,0
+LEFDE1:
+
+#endif /* defined(__MACH__) */
diff --git a/libphobos/libdruntime/config/x86/switchcontext.S b/libphobos/libdruntime/config/x86/switchcontext.S
index 82420c6..9f4befd 100644
--- a/libphobos/libdruntime/config/x86/switchcontext.S
+++ b/libphobos/libdruntime/config/x86/switchcontext.S
@@ -29,7 +29,11 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 # include <cet.h>
 #endif
 
-#if defined(__i386__) && !defined(__CET__)
+#if !defined(__CET__)
+
+# if defined(__ELF__)
+
+#  if defined(__i386__)
 
     .text
     .globl CSYM(fiber_switchContext)
@@ -63,7 +67,9 @@ CSYM(fiber_switchContext):
     .cfi_endproc
     .size CSYM(fiber_switchContext),.-CSYM(fiber_switchContext)
 
-#elif defined(__x86_64__) && !defined(__ILP32__) && !defined(__CET__)
+#  endif /* defined(__ELF__) && defined(__i386__) */
+
+#  if defined(__x86_64__) && !defined(__ILP32__)
 
     .text
     .globl CSYM(fiber_switchContext)
@@ -98,4 +104,151 @@ CSYM(fiber_switchContext):
     .cfi_endproc
    .size CSYM(fiber_switchContext),.-CSYM(fiber_switchContext)
 
-#endif
+#  endif /* defined(__ELF__) && defined(__x86_64__) && !defined(__ILP32__) */
+
+# endif /* defined(__ELF__) */
+
+# if defined(__MACH__)
+
+#  if defined(__i386__)
+
+    .text
+    .globl CSYM(fiber_switchContext)
+    .p2align 4
+CSYM(fiber_switchContext):
+LFB0:
+    // save current stack state
+    push %ebp
+    mov  %esp, %ebp
+    push %edi
+    push %esi
+    push %ebx
+    push %eax
+
+    // store oldp again with more accurate address
+    mov 8(%ebp), %eax
+    mov %esp, (%eax)
+    // load newp to begin context switch
+    mov 12(%ebp), %esp
+
+    // load saved state from new stack
+    pop %eax
+    pop %ebx
+    pop %esi
+    pop %edi
+    pop %ebp
+
+    // 'return' to complete switch
+    ret
+LFE0:
+
+/* CFI */
+        .section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
+EH_frame1:
+        .set L$set$0,LECIE1-LSCIE1
+        .long L$set$0   # Length of Common Information Entry
+LSCIE1:
+        .long   0       # CIE Identifier Tag
+        .byte   0x1     # CIE Version
+        .ascii "zR\0"   # CIE Augmentation
+        .byte   0x1     # uleb128 0x1; CIE Code Alignment Factor
+        .byte   0x7c    # sleb128 -4; CIE Data Alignment Factor
+        .byte   0x8     # CIE RA Column
+        .byte   0x1     # uleb128 0x1; Augmentation size
+        .byte   0x10    # FDE Encoding (pcrel)
+        .byte   0xc     # DW_CFA_def_cfa
+        .byte   0x5     # uleb128 0x5
+        .byte   0x4     # uleb128 0x4
+        .byte   0x88    # DW_CFA_offset, column 0x8
+        .byte   0x1     # uleb128 0x1
+        .p2align 2,0
+LECIE1:
+
+/* minimal FDE - does not record the stack frame changes. */
+LSFDE1:
+        .set L$set$1,LEFDE1-LASFDE1
+        .long L$set$1   # FDE Length
+LASFDE1:
+        .long   LASFDE1-EH_frame1       # FDE CIE offset
+        .long   LFB0-.  # FDE initial location
+        .set L$set$2,LFE0-LFB0
+        .long L$set$2   # FDE address range
+        .byte   0       # uleb128 0; Augmentation size
+        .p2align 2,0
+LEFDE1:
+
+#  endif /* defined(__MACH__) && defined(__i386__) */
+
+#  if defined(__x86_64__) && !defined(__ILP32__)
+
+    .text
+    .globl CSYM(fiber_switchContext)
+    .p2align 4
+CSYM(fiber_switchContext):
+LFB0:
+    // Save current stack state.save current stack state
+    push %rbp
+    mov  %rsp, %rbp
+    push %r15
+    push %r14
+    push %r13
+    push %r12
+    push %rbx
+
+    // store oldp again with more accurate address
+    mov %rsp, (%rdi)
+    // load newp to begin context switch
+    mov %rsi, %rsp
+
+    // load saved state from new stack
+    pop %rbx
+    pop %r12
+    pop %r13
+    pop %r14
+    pop %r15
+    pop %rbp
+
+    // 'return' to complete switch
+    ret
+LFE0:
+
+/* CFI */
+        .section __TEXT,__eh_frame,coalesced,no_toc+strip_static_syms+live_support
+EH_frame1:
+        .set L$set$0,LECIE1-LSCIE1
+        .long L$set$0   # Length of Common Information Entry
+LSCIE1:
+        .long   0       # CIE Identifier Tag
+        .byte   0x1     # CIE Version
+        .ascii "zR\0"   # CIE Augmentation
+        .byte   0x1     # uleb128 0x1; CIE Code Alignment Factor
+        .byte   0x78    # sleb128 -8; CIE Data Alignment Factor
+        .byte   0x10    # CIE RA Column
+        .byte   0x1     # uleb128 0x1; Augmentation size
+        .byte   0x10    # FDE Encoding (pcrel)
+        .byte   0xc     # DW_CFA_def_cfa
+        .byte   0x7     # uleb128 0x7
+        .byte   0x8     # uleb128 0x8
+        .byte   0x90    # DW_CFA_offset, column 0x10
+        .byte   0x1     # uleb128 0x1
+        .p2align 3,0
+LECIE1:
+
+/* minimal FDE - does not record the stack frame changes. */
+LSFDE1:
+        .set L$set$1,LEFDE1-LASFDE1
+        .long L$set$1   # FDE Length
+LASFDE1:
+        .long   LASFDE1-EH_frame1       # FDE CIE offset
+        .quad   LFB0-.  # FDE initial location
+        .set L$set$2,LFE0-LFB0
+        .quad L$set$2   # FDE address range
+        .byte   0       # uleb128 0; Augmentation size
+        .p2align 3,0
+LEFDE1:
+
+#  endif /* defined(__MACH__) && defined(__x86_64__) && !defined(__ILP32__) */
+
+# endif /* defined (__MACH__) */
+
+#endif /* !defined(__CET__) */
diff --git a/libphobos/libdruntime/core/stdc/complex.d b/libphobos/libdruntime/core/stdc/complex.d
index d878366..b84651f 100644
--- a/libphobos/libdruntime/core/stdc/complex.d
+++ b/libphobos/libdruntime/core/stdc/complex.d
@@ -19,163 +19,97 @@ extern (C):
 nothrow:
 @nogc:
 
-///
+// @@@DEPRECATED_2.105@@@
+deprecated:
 alias creal complex;
-///
 alias ireal imaginary;
-///
 cdouble cacos(cdouble z);
-///
 cfloat  cacosf(cfloat z);
-///
 creal   cacosl(creal z);
 
-///
 cdouble casin(cdouble z);
-///
 cfloat  casinf(cfloat z);
-///
 creal   casinl(creal z);
 
-///
 cdouble catan(cdouble z);
-///
 cfloat  catanf(cfloat z);
-///
 creal   catanl(creal z);
 
-///
 cdouble ccos(cdouble z);
-///
 cfloat  ccosf(cfloat z);
-///
 creal   ccosl(creal z);
 
-///
 cdouble csin(cdouble z);
-///
 cfloat  csinf(cfloat z);
-///
 creal   csinl(creal z);
 
-///
 cdouble ctan(cdouble z);
-///
 cfloat  ctanf(cfloat z);
-///
 creal   ctanl(creal z);
 
-///
 cdouble cacosh(cdouble z);
-///
 cfloat  cacoshf(cfloat z);
-///
 creal   cacoshl(creal z);
 
-///
 cdouble casinh(cdouble z);
-///
 cfloat  casinhf(cfloat z);
-///
 creal   casinhl(creal z);
 
-///
 cdouble catanh(cdouble z);
-///
 cfloat  catanhf(cfloat z);
-///
 creal   catanhl(creal z);
 
-///
 cdouble ccosh(cdouble z);
-///
 cfloat  ccoshf(cfloat z);
-///
 creal   ccoshl(creal z);
 
-///
 cdouble csinh(cdouble z);
-///
 cfloat  csinhf(cfloat z);
-///
 creal   csinhl(creal z);
 
-///
 cdouble ctanh(cdouble z);
-///
 cfloat  ctanhf(cfloat z);
-///
 creal   ctanhl(creal z);
 
-///
 cdouble cexp(cdouble z);
-///
 cfloat  cexpf(cfloat z);
-///
 creal   cexpl(creal z);
 
-///
 cdouble clog(cdouble z);
-///
 cfloat  clogf(cfloat z);
-///
 creal   clogl(creal z);
 
-///
  double cabs(cdouble z);
- ///
  float  cabsf(cfloat z);
- ///
  real   cabsl(creal z);
 
- ///
 cdouble cpow(cdouble x, cdouble y);
-///
 cfloat  cpowf(cfloat x, cfloat y);
-///
 creal   cpowl(creal x, creal y);
 
-///
 cdouble csqrt(cdouble z);
-///
 cfloat  csqrtf(cfloat z);
-///
 creal   csqrtl(creal z);
 
-///
  double carg(cdouble z);
- ///
  float  cargf(cfloat z);
- ///
  real   cargl(creal z);
 
-///
 pragma(inline, true) double cimag(cdouble z) { return z.im; }
-///
 pragma(inline, true) float  cimagf(cfloat z) { return z.im; }
-///
 pragma(inline, true) real   cimagl(creal z)  { return z.im; }
 
-///
 cdouble conj(cdouble z);
-///
 cfloat  conjf(cfloat z);
-///
 creal   conjl(creal z);
 
-///
 cdouble cproj(cdouble z);
-///
 cfloat  cprojf(cfloat z);
-///
 creal   cprojl(creal z);
 
 // Note: `creal` is a keyword in D and so this function is inaccessible, use `creald` instead
 //pragma(inline, true) double creal(cdouble z) { return z.re; }
 
-///
 pragma(inline, true) double creald(cdouble z) { return z.re; }
-///
 pragma(inline, true) float  crealf(cfloat z) { return z.re; }
-///
 pragma(inline, true) real   creall(creal z)  { return z.re; }
diff --git a/libphobos/libdruntime/core/stdc/config.d b/libphobos/libdruntime/core/stdc/config.d
index cdb987f..44bb707 100644
--- a/libphobos/libdruntime/core/stdc/config.d
+++ b/libphobos/libdruntime/core/stdc/config.d
@@ -34,6 +34,7 @@ version (StdDdoc)
             alias ddoc_long = int;
             alias ddoc_ulong = uint;
         }
+        struct ddoc_complex(T) { T re; T im; };
     }
 
     /***
@@ -89,6 +90,24 @@ version (StdDdoc)
      * C++ compiler's `ptrdiff_t` type.
      */
     alias cpp_ptrdiff_t = ptrdiff_t;
+
+    /***
+     * Used for a complex floating point type that corresponds in size and ABI to the associated
+     * C compiler's `_Complex float` type.
+     */
+    alias c_complex_float = ddoc_complex!float;
+
+    /***
+     * Used for a complex floating point type that corresponds in size and ABI to the associated
+     * C compiler's `_Complex double` type.
+     */
+    alias c_complex_double = ddoc_complex!double;
+
+    /***
+     * Used for a complex floating point type that corresponds in size and ABI to the associated
+     * C compiler's `_Complex long double` type.
+     */
+    alias c_complex_real = ddoc_complex!real;
 }
 else
 {
@@ -167,7 +186,18 @@ else version (Posix)
   }
 }
 
-version (CRuntime_Microsoft)
+version (GNU)
+    alias c_long_double = real;
+else version (LDC)
+    alias c_long_double = real; // 64-bit real for MSVC targets
+else version (SDC)
+{
+    version (X86)
+        alias c_long_double = real;
+    else version (X86_64)
+        alias c_long_double = real;
+}
+else version (CRuntime_Microsoft)
 {
     /* long double is 64 bits, not 80 bits, but is mangled differently
      * than double. To distinguish double from long double, create a wrapper to represent
@@ -203,17 +233,6 @@ else version (DigitalMars)
             alias real c_long_double;
     }
 }
-else version (GNU)
-    alias real c_long_double;
-else version (LDC)
-    alias real c_long_double;
-else version (SDC)
-{
-    version (X86)
-        alias real c_long_double;
-    else version (X86_64)
-        alias real c_long_double;
-}
 
 static assert(is(c_long_double), "c_long_double needs to be declared for this platform/architecture.");
 
@@ -230,4 +249,19 @@ else
     alias cpp_size_t = size_t;
     alias cpp_ptrdiff_t = ptrdiff_t;
 }
+
+// ABI layout of native complex types.
+private struct _Complex(T)
+{
+    T re;
+    T im;
+}
+
+enum __c_complex_float  : _Complex!float;
+enum __c_complex_double : _Complex!double;
+enum __c_complex_real   : _Complex!c_long_double;
+
+alias c_complex_float = __c_complex_float;
+alias c_complex_double = __c_complex_double;
+alias c_complex_real = __c_complex_real;
 }
diff --git a/libphobos/libdruntime/core/stdc/errno.d b/libphobos/libdruntime/core/stdc/errno.d
index 31f7d11..57bc15d 100644
--- a/libphobos/libdruntime/core/stdc/errno.d
+++ b/libphobos/libdruntime/core/stdc/errno.d
@@ -156,15 +156,9 @@ else version (Haiku)
 else
 {
     ///
-    @property int errno() { return getErrno(); }
+    extern(C) pragma(mangle, "getErrno") @property int errno();
     ///
-    @property int errno(int n) { return setErrno(n); }
-
-    extern (C)
-    {
-        private int getErrno();      // for internal use
-        private int setErrno(int);   // for internal use
-    }
+    extern(C) pragma(mangle, "setErrno") @property int errno(int n);
 }
 
 extern (C):
@@ -1532,7 +1526,11 @@ else version (OpenBSD)
     enum EIDRM              = 89;       /// Identifier removed
     enum ENOMSG             = 90;       /// No message of desired type
     enum ENOTSUP            = 91;       /// Not supported
-    enum ELAST              = 91;       /// Must be equal largest errno
+    enum EBADMSG            = 92;       /// Bad message
+    enum ENOTRECOVERABLE    = 93;       /// State not recoverable
+    enum EOWNERDEAD         = 94;       /// Previous owner died
+    enum EPROTO             = 95;       /// Protocol error
+    enum ELAST              = 95;       /// Must be equal largest errno
 }
 else version (DragonFlyBSD)
 {
diff --git a/libphobos/libdruntime/core/stdc/math.d b/libphobos/libdruntime/core/stdc/math.d
index e8d1fa8..2de6e57 100644
--- a/libphobos/libdruntime/core/stdc/math.d
+++ b/libphobos/libdruntime/core/stdc/math.d
@@ -319,16 +319,12 @@ version (CRuntime_DigitalMars)
   {
     //int fpclassify(real-floating x);
     ///
-    pure int fpclassify(float x)     { return __fpclassify_f(x); }
+    extern(C) pragma(mangle, "__fpclassify_f") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassify_d(x); }
+    extern(C) pragma(mangle, "__fpclassify_d") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassify_d(x)
-            : __fpclassify_ld(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassify_d" : "__fpclassify_ld")
+    pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
@@ -428,98 +424,177 @@ else version (CRuntime_Microsoft) // fully supported since MSVCRT 12 (VS 2013) o
     pure int _fpclass(double x);
   }
 
+  version (MinGW)
+  {
     enum
     {
         ///
-        FP_SUBNORMAL = -2,
+        FP_NAN = 0x0100,
         ///
-        FP_NORMAL    = -1,
+        FP_NORMAL = 0x0400,
         ///
-        FP_ZERO      =  0,
+        FP_INFINITE = FP_NAN | FP_NORMAL,
         ///
-        FP_INFINITE  =  1,
+        FP_ZERO = 0x0400,
         ///
-        FP_NAN       =  2,
+        FP_SUBNORMAL = FP_NORMAL | FP_ZERO
     }
 
-    pure private short _fdclass(float x);
-    pure private short _dclass(double x);
+    pure int __fpclassifyf(float x);
+    pure int __fpclassify(double x);
+    pure int __fpclassifyl(real x);
 
-    pure private int _fdsign(float x);
-    pure private int _dsign(double x);
+    pure int __isnanf(float x);
+    pure int __isnan(double x);
+    pure int __isnanl(real x);
 
-  extern(D)
-  {
-    //int fpclassify(real-floating x);
-    ///
-    pure int fpclassify()(float x)   { return _fdclass(x); }
-    ///
-    pure int fpclassify()(double x)  { return _dclass(x);  }
-    ///
-    pure int fpclassify()(real x)
+    pure int __signbitf(float x);
+    pure int __signbit(double x);
+    pure int __signbitl(real x);
+
+    extern (D)
     {
-        static if (real.sizeof == double.sizeof)
-            return _dclass(cast(double) x);
-        else
-            static assert(false, "fpclassify(real) not supported by MS C runtime");
-    }
+        //int fpclassify(real-floating x);
+        ///
+        extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
+        ///
+        extern(C) pragma(mangle, "__fpclassify")  pure int fpclassify(double x);
+        ///
+        extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassify" : "__fpclassifyl")
+            pure int fpclassify(real x);
 
-    //int isfinite(real-floating x);
-    ///
-    pure int isfinite()(float x)     { return fpclassify(x) <= 0; }
-    ///
-    pure int isfinite()(double x)    { return fpclassify(x) <= 0; }
-    ///
-    pure int isfinite()(real x)      { return fpclassify(x) <= 0; }
+        //int isfinite(real-floating x);
+        ///
+        pure int isfinite(float x)       { return (fpclassify(x) & FP_NORMAL) == 0; }
+        ///
+        pure int isfinite(double x)      { return (fpclassify(x) & FP_NORMAL) == 0; }
+        ///
+        pure int isfinite(real x)        { return (fpclassify(x) & FP_NORMAL) == 0; }
 
-    //int isinf(real-floating x);
-    ///
-    pure int isinf()(float x)        { return fpclassify(x) == FP_INFINITE; }
-    ///
-    pure int isinf()(double x)       { return fpclassify(x) == FP_INFINITE; }
-    ///
-    pure int isinf()(real x)         { return fpclassify(x) == FP_INFINITE; }
+        //int isinf(real-floating x);
+        ///
+        pure int isinf(float x)          { return fpclassify(x) == FP_INFINITE; }
+        ///
+        pure int isinf(double x)         { return fpclassify(x) == FP_INFINITE; }
+        ///
+        pure int isinf(real x)           { return fpclassify(x) == FP_INFINITE; }
 
-    //int isnan(real-floating x);
-    version (none) // requires MSVCRT 12+ (VS 2013)
-    {
+        //int isnan(real-floating x);
+        ///
+        extern(C) pragma(mangle, "__isnanf") pure int isnan(float x);
+        ///
+        extern(C) pragma(mangle, "__isnan")  pure int isnan(double x);
+        ///
+        extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isnan" : "__isnanl")
+            pure int isnan(real x);
+
+        //int isnormal(real-floating x);
+        ///
+        int isnormal(float x)       { return fpclassify(x) == FP_NORMAL; }
+        ///
+        int isnormal(double x)      { return fpclassify(x) == FP_NORMAL; }
+        ///
+        int isnormal(real x)        { return fpclassify(x) == FP_NORMAL; }
+
+        //int signbit(real-floating x);
         ///
-        pure int isnan(float x)      { return fpclassify(x) == FP_NAN; }
+        extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
         ///
-        pure int isnan(double x)     { return fpclassify(x) == FP_NAN; }
+        extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
         ///
-        pure int isnan(real x)       { return fpclassify(x) == FP_NAN; }
+        extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__signbit" : "__signbitl")
+            int signbit(real x);
     }
-    else // for backward compatibility with older runtimes
+  }
+  else
+  {
+    enum
     {
         ///
-        pure int isnan(float x)      { version (Win64) return _isnanf(x); else return _isnan(cast(double) x); }
+        FP_SUBNORMAL = -2,
+        ///
+        FP_NORMAL    = -1,
         ///
-        pure int isnan(double x)     { return _isnan(x); }
+        FP_ZERO      =  0,
         ///
-        pure int isnan(real x)       { return _isnan(cast(double) x); }
+        FP_INFINITE  =  1,
+        ///
+        FP_NAN       =  2,
     }
 
-    //int isnormal(real-floating x);
-    ///
-    pure int isnormal()(float x)     { return fpclassify(x) == FP_NORMAL; }
-    ///
-    pure int isnormal()(double x)    { return fpclassify(x) == FP_NORMAL; }
-    ///
-    pure int isnormal()(real x)      { return fpclassify(x) == FP_NORMAL; }
-
-    //int signbit(real-floating x);
-    ///
-    pure int signbit()(float x)   { return _fdsign(x); }
-    ///
-    pure int signbit()(double x)  { return _dsign(x);  }
-    ///
-    pure int signbit()(real x)
+    extern(D)
     {
-        static if (real.sizeof == double.sizeof)
-            return _dsign(cast(double) x);
-        else
-            return (cast(short*)&(x))[4] & 0x8000;
+        //int fpclassify(real-floating x);
+        ///
+        extern(C) pragma(mangle, "_fdclass") pure int fpclassify(float x);
+        ///
+        extern(C) pragma(mangle, "_dclass")  pure int fpclassify(double x);
+        ///
+        pure int fpclassify()(real x)
+        {
+            static if (real.sizeof == double.sizeof)
+                return fpclassify(cast(double) x);
+            else
+                static assert(false, "fpclassify(real) not supported by MS C runtime");
+        }
+
+        //int isfinite(real-floating x);
+        ///
+        pure int isfinite()(float x)     { return fpclassify(x) <= 0; }
+        ///
+        pure int isfinite()(double x)    { return fpclassify(x) <= 0; }
+        ///
+        pure int isfinite()(real x)      { return fpclassify(x) <= 0; }
+
+        //int isinf(real-floating x);
+        ///
+        pure int isinf()(float x)        { return fpclassify(x) == FP_INFINITE; }
+        ///
+        pure int isinf()(double x)       { return fpclassify(x) == FP_INFINITE; }
+        ///
+        pure int isinf()(real x)         { return fpclassify(x) == FP_INFINITE; }
+
+        //int isnan(real-floating x);
+        version (none) // requires MSVCRT 12+ (VS 2013)
+        {
+            ///
+            pure int isnan(float x)      { return fpclassify(x) == FP_NAN; }
+            ///
+            pure int isnan(double x)     { return fpclassify(x) == FP_NAN; }
+            ///
+            pure int isnan(real x)       { return fpclassify(x) == FP_NAN; }
+        }
+        else // for backward compatibility with older runtimes
+        {
+            ///
+            pure int isnan(float x)      { version (Win64) return _isnanf(x); else return _isnan(cast(double) x); }
+            ///
+            extern(C) pragma(mangle, "_isnan") pure int isnan(double x);
+            ///
+            pure int isnan(real x)       { return _isnan(cast(double) x); }
+        }
+
+        //int isnormal(real-floating x);
+        ///
+        pure int isnormal()(float x)     { return fpclassify(x) == FP_NORMAL; }
+        ///
+        pure int isnormal()(double x)    { return fpclassify(x) == FP_NORMAL; }
+        ///
+        pure int isnormal()(real x)      { return fpclassify(x) == FP_NORMAL; }
+
+        //int signbit(real-floating x);
+        ///
+        extern(C) pragma(mangle, "_fdsign") pure int signbit(float x);
+        ///
+        extern(C) pragma(mangle, "_dsign")  pure int signbit(double x);
+        ///
+        pure int signbit()(real x)
+        {
+            static if (real.sizeof == double.sizeof)
+                return signbit(cast(double) x);
+            else
+                return (cast(short*)&(x))[4] & 0x8000;
+        }
     }
   }
 }
@@ -573,55 +648,39 @@ else version (CRuntime_Glibc)
   {
     //int fpclassify(real-floating x);
       ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassify(x);  }
+    extern(C) pragma(mangle, "__fpclassify")  pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassify(x)
-            : __fpclassifyl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassify" : "__fpclassifyl")
+    pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return __finitef(x); }
+    extern(C) pragma(mangle, "__finitef") pure int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return __finite(x);  }
+    extern(C) pragma(mangle, "__finite")  pure int isfinite(double x);
     ///
-    pure int isfinite(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __finite(x)
-            : __finitel(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__finite" : "__finitel")
+    pure int isfinite(real x);
 
     //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return __isinff(x);  }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
     ///
-    pure int isinf(double x)         { return __isinf(x);   }
+    extern(C) pragma(mangle, "__isinf")  pure int isinf(double x);
     ///
-    pure int isinf(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isinf(x)
-            : __isinfl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isinf" : "__isinfl")
+    pure int isinf(real x);
 
     //int isnan(real-floating x);
     ///
-    pure int isnan(float x)          { return __isnanf(x);  }
+    extern(C) pragma(mangle, "__isnanf") pure int isnan(float x);
     ///
-    pure int isnan(double x)         { return __isnan(x);   }
+    extern(C) pragma(mangle, "__isnan")  pure int isnan(double x);
     ///
-    pure int isnan(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isnan(x)
-            : __isnanl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isnan" : "__isnanl")
+    pure int isnan(real x);
 
     //int isnormal(real-floating x);
     ///
@@ -633,16 +692,12 @@ else version (CRuntime_Glibc)
 
     //int signbit(real-floating x);
     ///
-    pure int signbit(float x)     { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
     ///
-    pure int signbit(double x)    { return __signbit(x);  }
+    extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
     ///
-    pure int signbit(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __signbit(x)
-            : __signbitl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__signbit" : "__signbitl")
+    pure int signbit(real x);
   }
 }
 else version (CRuntime_Musl)
@@ -685,16 +740,12 @@ else version (CRuntime_Musl)
   {
     //int fpclassify(real-floating x);
       ///
-    int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") int fpclassify(float x);
     ///
-    int fpclassify(double x)    { return __fpclassify(x);  }
+    extern(C) pragma(mangle, "__fpclassify")  int fpclassify(double x);
     ///
-    int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassify(x)
-            : __fpclassifyl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassify" : "__fpclassifyl")
+    int fpclassify(real x);
     private uint __FLOAT_BITS(float __f)
     {
         union __u_t {
@@ -765,16 +816,12 @@ else version (CRuntime_Musl)
 
     //int signbit(real-floating x);
     ///
-    int signbit(float x)     { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") int signbit(float x);
     ///
-    int signbit(double x)    { return __signbit(x);  }
+    extern(C) pragma(mangle, "__signbit")  int signbit(double x);
     ///
-    int signbit(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __signbit(x)
-            : __signbitl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__signbit" : "__signbitl")
+    int signbit(real x);
   }
 }
 else version (CRuntime_UClibc)
@@ -826,146 +873,37 @@ else version (CRuntime_UClibc)
   extern (D)
   {
     ///
-    int fpclassify(float x)     { return __fpclassifyf(x); }
-    ///
-    int fpclassify(double x)    { return __fpclassify(x);  }
-    ///
-    int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassify(x)
-            : __fpclassifyl(x);
-    }
-
-    ///
-    int isfinite(float x)       { return __finitef(x); }
-    ///
-    int isfinite(double x)      { return __finite(x);  }
-    ///
-    int isfinite(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __finite(x)
-            : __finitel(x);
-    }
-
-    ///
-    int isinf(float x)          { return __isinff(x);  }
-    ///
-    int isinf(double x)         { return __isinf(x);   }
-    ///
-    int isinf(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isinf(x)
-            : __isinfl(x);
-    }
-
-    ///
-    int isnan(float x)          { return __isnanf(x);  }
-    ///
-    int isnan(double x)         { return __isnan(x);   }
-    ///
-    int isnan(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isnan(x)
-            : __isnanl(x);
-    }
-
-    ///
-    int isnormal(float x)       { return fpclassify(x) == FP_NORMAL; }
-    ///
-    int isnormal(double x)      { return fpclassify(x) == FP_NORMAL; }
-    ///
-    int isnormal(real x)        { return fpclassify(x) == FP_NORMAL; }
-
-    ///
-    int signbit(float x)     { return __signbitf(x); }
-    ///
-    int signbit(double x)    { return __signbit(x);  }
-    ///
-    int signbit(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __signbit(x)
-            : __signbitl(x);
-    }
-  }
-}
-else version (MinGW)
-{
-    enum
-    {
-        ///
-        FP_NAN = 0x0100,
-        ///
-        FP_NORMAL = 0x0400,
-        ///
-        FP_INFINITE = FP_NAN | FP_NORMAL,
-        ///
-        FP_ZERO = 0x0400,
-        ///
-        FP_SUBNORMAL = FP_NORMAL | FP_ZERO
-    }
-
-    pure int __fpclassifyf(float x);
-    pure int __fpclassify(double x);
-    pure int __fpclassifyl(real x);
-
-    pure int __isnanf(float x);
-    pure int __isnan(double x);
-    pure int __isnanl(real x);
-
-    pure int __signbitf(float x);
-    pure int __signbit(double x);
-    pure int __signbitl(real x);
-
-  extern (D)
-  {
-    //int fpclassify(real-floating x);
-      ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassify(x);  }
+    extern(C) pragma(mangle, "__fpclassify")  int fpclassify(double x);
     ///
-    pure int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassify(x)
-            : __fpclassifyl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassify" : "__fpclassifyl")
+    int fpclassify(real x);
 
-    //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return (fpclassify(x) & FP_NORMAL) == 0; }
+    extern(C) pragma(mangle, "__finitef") int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return (fpclassify(x) & FP_NORMAL) == 0; }
+    extern(C) pragma(mangle, "__finite")  int isfinite(double x);
     ///
-    pure int isfinite(real x)        { return (fpclassify(x) & FP_NORMAL) == 0; }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__finite" : "__finitel")
+    int isfinite(real x);
 
-    //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return fpclassify(x) == FP_INFINITE; }
+    extern(C) pragma(mangle, "__isinff") int isinf(float x);
     ///
-    pure int isinf(double x)         { return fpclassify(x) == FP_INFINITE; }
+    extern(C) pragma(mangle, "__isinf")  int isinf(double x);
     ///
-    pure int isinf(real x)           { return fpclassify(x) == FP_INFINITE; }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isinf" : "__isinfl")
+    int isinf(real x);
 
-    //int isnan(real-floating x);
     ///
-    pure int isnan(float x)          { return __isnanf(x);  }
+    extern(C) pragma(mangle, "__isnanf") int isnan(float x);
     ///
-    pure int isnan(double x)         { return __isnan(x);   }
+    extern(C) pragma(mangle, "__isnan")  int isnan(double x);
     ///
-    pure int isnan(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isnan(x)
-            : __isnanl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isnan" : "__isnanl")
+    int isnan(real x);
 
-    //int isnormal(real-floating x);
     ///
     int isnormal(float x)       { return fpclassify(x) == FP_NORMAL; }
     ///
@@ -973,18 +911,13 @@ else version (MinGW)
     ///
     int isnormal(real x)        { return fpclassify(x) == FP_NORMAL; }
 
-    //int signbit(real-floating x);
     ///
-    int signbit(float x)     { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") int signbit(float x);
     ///
-    int signbit(double x)    { return __signbit(x);  }
+    extern(C) pragma(mangle, "__signbit")  int signbit(double x);
     ///
-    int signbit(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __signbit(x)
-            : __signbitl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__signbit" : "__signbitl")
+    int signbit(real x);
   }
 }
 else version (Darwin)
@@ -1070,35 +1003,35 @@ else version (Darwin)
   {
     //int fpclassify(real-floating x);
     ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
+    extern(C) pragma(mangle, "__fpclassifyd") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)      { return __fpclassifyl(x); }
+    extern(C) pragma(mangle, __fpclassifyl.mangleof) pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return __isfinitef(x); }
+    extern(C) pragma(mangle, "__isfinitef") pure int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return __isfinited(x); }
+    extern(C) pragma(mangle, "__isfinited") pure int isfinite(double x);
     ///
-    pure int isfinite(real x)        { return __isfinitel(x); }
+    extern(C) pragma(mangle, __isfinitel.mangleof) pure int isfinite(real x);
 
     //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return __isinff(x); }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
     ///
-    pure int isinf(double x)         { return __isinfd(x); }
+    extern(C) pragma(mangle, "__isinfd") pure int isinf(double x);
     ///
-    pure int isinf(real x)           { return __isinfl(x); }
+    extern(C) pragma(mangle, __isinfl.mangleof) pure int isinf(real x);
 
     //int isnan(real-floating x);
     ///
-    pure int isnan(float x)          { return __isnanf(x); }
+    extern(C) pragma(mangle, "__isnanf") pure int isnan(float x);
     ///
-    pure int isnan(double x)         { return __isnand(x); }
+    extern(C) pragma(mangle, "__isnand") pure int isnan(double x);
     ///
-    pure int isnan(real x)           { return __isnanl(x); }
+    extern(C) pragma(mangle, __isnanl.mangleof) pure int isnan(real x);
 
     //int isnormal(real-floating x);
     ///
@@ -1110,11 +1043,11 @@ else version (Darwin)
 
     //int signbit(real-floating x);
     ///
-    pure int signbit(float x)     { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
     ///
-    pure int signbit(double x)    { return __signbitd(x); }
+    extern(C) pragma(mangle, "__signbitd") pure int signbit(double x);
     ///
-    pure int signbit(real x)      { return __signbitl(x); }
+    extern(C) pragma(mangle, "__signbitl") pure int signbit(real x);
   }
 }
 else version (FreeBSD)
@@ -1163,27 +1096,27 @@ else version (FreeBSD)
   {
     //int fpclassify(real-floating x);
       ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
+    extern(C) pragma(mangle, "__fpclassifyd") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)      { return __fpclassifyl(x); }
+    extern(C) pragma(mangle, "__fpclassifyl") pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return __isfinitef(x); }
+    extern(C) pragma(mangle, "__isfinitef") pure int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return __isfinite(x); }
+    extern(C) pragma(mangle, "__isfinite")  pure int isfinite(double x);
     ///
-    pure int isfinite(real x)        { return __isfinitel(x); }
+    extern(C) pragma(mangle, "__isfinitel") pure int isfinite(real x);
 
     //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return __isinff(x); }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
     ///
     pure int isinf(double x)         { return __isinfl(x); }
     ///
-    pure int isinf(real x)           { return __isinfl(x); }
+    extern(C) pragma(mangle, "__isinfl") pure int isinf(real x);
 
     //int isnan(real-floating x);
     ///
@@ -1191,21 +1124,21 @@ else version (FreeBSD)
     ///
     pure int isnan(double x)         { return __isnanl(x); }
     ///
-    pure int isnan(real x)           { return __isnanl(x); }
+    extern(C) pragma(mangle, "__isnanl") pure int isnan(real x);
 
     //int isnormal(real-floating x);
     ///
-    pure int isnormal(float x)       { return __isnormalf(x); }
+    extern(C) pragma(mangle, "__isnormalf") pure int isnormal(float x);
     ///
-    pure int isnormal(double x)      { return __isnormal(x); }
+    extern(C) pragma(mangle, "__isnormal")  pure int isnormal(double x);
     ///
-    pure int isnormal(real x)        { return __isnormall(x); }
+    extern(C) pragma(mangle, "__isnormall") pure int isnormal(real x);
 
     //int signbit(real-floating x);
     ///
-    pure int signbit(float x)        { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
     ///
-    pure int signbit(double x)       { return __signbit(x); }
+    extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
     ///
     pure int signbit(real x)         { return __signbit(x); }
   }
@@ -1236,7 +1169,7 @@ else version (OpenBSD)
         FP_FAST_FMAL = 1,
     }
 
-    pure int __fpclassifyd(double);
+    pure int __fpclassify(double);
     pure int __fpclassifyf(float);
     pure int __fpclassifyl(real);
     pure int __isfinitef(float);
@@ -1256,27 +1189,27 @@ else version (OpenBSD)
   {
     //int fpclassify(real-floating x);
       ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
+    extern(C) pragma(mangle, "__fpclassify") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)      { return __fpclassifyl(x); }
+    extern(C) pragma(mangle, "__fpclassifyl") pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return __isfinitef(x); }
+    extern(C) pragma(mangle, "__isfinitef") pure int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return __isfinite(x); }
+    extern(C) pragma(mangle, "__isfinite")  pure int isfinite(double x);
     ///
-    pure int isfinite(real x)        { return __isfinitel(x); }
+    extern(C) pragma(mangle, "__isfinitel") pure int isfinite(real x);
 
     //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return __isinff(x); }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
     ///
     pure int isinf(double x)         { return __isinfl(x); }
     ///
-    pure int isinf(real x)           { return __isinfl(x); }
+    extern(C) pragma(mangle, "__isinfl") pure int isinf(real x);
 
     //int isnan(real-floating x);
     ///
@@ -1284,21 +1217,21 @@ else version (OpenBSD)
     ///
     pure int isnan(double x)         { return __isnanl(x); }
     ///
-    pure int isnan(real x)           { return __isnanl(x); }
+    extern(C) pragma(mangle, "__isnanl") pure int isnan(real x);
 
     //int isnormal(real-floating x);
     ///
-    pure int isnormal(float x)       { return __isnormalf(x); }
+    extern(C) pragma(mangle, "__isnormalf") pure int isnormal(float x);
     ///
-    pure int isnormal(double x)      { return __isnormal(x); }
+    extern(C) pragma(mangle, "__isnormal")  pure int isnormal(double x);
     ///
-    pure int isnormal(real x)        { return __isnormall(x); }
+    extern(C) pragma(mangle, "__isnormall") pure int isnormal(real x);
 
     //int signbit(real-floating x);
     ///
-    pure int signbit(float x)        { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
     ///
-    pure int signbit(double x)       { return __signbit(x); }
+    extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
     ///
     pure int signbit(real x)         { return __signbit(x); }
   }
@@ -1337,16 +1270,12 @@ else version (NetBSD)
   {
     //int fpclassify(real-floating x);
     ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
+    extern(C) pragma(mangle, "__fpclassifyd") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __fpclassifyd(x)
-            : __fpclassifyl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__fpclassifyd" : "__fpclassifyl")
+    pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
@@ -1433,29 +1362,29 @@ else version (DragonFlyBSD)
 
   extern (D)
   {
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
-    pure int fpclassify(real x)      { return __fpclassifyl(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
+    extern(C) pragma(mangle, "__fpclassifyd") pure int fpclassify(double x);
+    extern(C) pragma(mangle, "__fpclassifyl") pure int fpclassify(real x);
 
-    pure int isfinite(float x)       { return __isfinitef(x); }
-    pure int isfinite(double x)      { return __isfinite(x); }
-    pure int isfinite(real x)        { return __isfinitel(x); }
+    extern(C) pragma(mangle, "__isfinitef") pure int isfinite(float x);
+    extern(C) pragma(mangle, "__isfinite")  pure int isfinite(double x);
+    extern(C) pragma(mangle, "__isfinitel") pure int isfinite(real x);
 
-    pure int isinf(float x)          { return __isinff(x); }
-    pure int isinf(double x)         { return __isinf(x); }
-    pure int isinf(real x)           { return __isinfl(x); }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
+    extern(C) pragma(mangle, "__isinf")  pure int isinf(double x);
+    extern(C) pragma(mangle, "__isinfl") pure int isinf(real x);
 
-    pure int isnan(float x)          { return __isnanf(x); }
-    pure int isnan(double x)         { return __isnan(x); }
-    pure int isnan(real x)           { return __isnanl(x); }
+    extern(C) pragma(mangle, "__isnanf") pure int isnan(float x);
+    extern(C) pragma(mangle, "__isnan")  pure int isnan(double x);
+    extern(C) pragma(mangle, "__isnanl") pure int isnan(real x);
 
-    pure int isnormal(float x)       { return __isnormalf(x); }
-    pure int isnormal(double x)      { return __isnormal(x); }
-    pure int isnormal(real x)        { return __isnormall(x); }
+    extern(C) pragma(mangle, "__isnormalf") pure int isnormal(float x);
+    extern(C) pragma(mangle, "__isnormal")  pure int isnormal(double x);
+    extern(C) pragma(mangle, "__isnormall") pure int isnormal(real x);
 
-    pure int signbit(float x)        { return __signbitf(x); }
-    pure int signbit(double x)       { return __signbit(x); }
-    pure int signbit(real x)         { return __signbitl(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
+    extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
+    extern(C) pragma(mangle, "__signbitl") pure int signbit(real x);
   }
 }
 else version (Solaris)
@@ -1468,16 +1397,12 @@ else version (Solaris)
   {
     //int isnan(real-floating x);
       ///
-    pure int isnan(float x)          { return __isnanf(x);  }
+    extern(C) pragma(mangle, "__isnanf") pure int isnan(float x);
     ///
-    pure int isnan(double x)         { return __isnan(x);   }
+    extern(C) pragma(mangle, "__isnan")  pure int isnan(double x);
     ///
-    pure int isnan(real x)
-    {
-        return (real.sizeof == double.sizeof)
-            ? __isnan(x)
-            : __isnanl(x);
-    }
+    extern(C) pragma(mangle, real.sizeof == double.sizeof ? "__isnan" : "__isnanl")
+    pure int isnan(real x);
   }
 }
 else version (CRuntime_Bionic)
@@ -1527,49 +1452,49 @@ else version (CRuntime_Bionic)
   {
     //int fpclassify(real-floating x);
       ///
-    pure int fpclassify(float x)     { return __fpclassifyf(x); }
+    extern(C) pragma(mangle, "__fpclassifyf") pure int fpclassify(float x);
     ///
-    pure int fpclassify(double x)    { return __fpclassifyd(x); }
+    extern(C) pragma(mangle, "__fpclassifyd") pure int fpclassify(double x);
     ///
-    pure int fpclassify(real x)      { return __fpclassifyl(x); }
+    extern(C) pragma(mangle, "__fpclassifyl") pure int fpclassify(real x);
 
     //int isfinite(real-floating x);
     ///
-    pure int isfinite(float x)       { return __isfinitef(x); }
+    extern(C) pragma(mangle, "__isfinitef") pure int isfinite(float x);
     ///
-    pure int isfinite(double x)      { return __isfinite(x); }
+    extern(C) pragma(mangle, "__isfinite")  pure int isfinite(double x);
     ///
-    pure int isfinite(real x)        { return __isfinitel(x); }
+    extern(C) pragma(mangle, "__isfinitel") pure int isfinite(real x);
 
     //int isinf(real-floating x);
     ///
-    pure int isinf(float x)          { return __isinff(x); }
+    extern(C) pragma(mangle, "__isinff") pure int isinf(float x);
     ///
-    pure int isinf(double x)         { return __isinf(x); }
+    extern(C) pragma(mangle, "__isinf")  pure int isinf(double x);
     ///
-    pure int isinf(real x)           { return __isinfl(x); }
+    extern(C) pragma(mangle, "__isinfl") pure int isinf(real x);
 
     //int isnan(real-floating x);
     ///
-    pure int isnan(float x)          { return isnanf(x); }
+    extern(C) pragma(mangle, "isnanf")   pure int isnan(float x);
     ///
-    pure int isnan(real x)           { return __isnanl(x); }
+    extern(C) pragma(mangle, "__isnanl") pure int isnan(real x);
 
     //int isnormal(real-floating x);
     ///
-    pure int isnormal(float x)       { return __isnormalf(x); }
+    extern(C) pragma(mangle, "__isnormalf") pure int isnormal(float x);
     ///
-    pure int isnormal(double x)      { return __isnormal(x); }
+    extern(C) pragma(mangle, "__isnormal")  pure int isnormal(double x);
     ///
-    pure int isnormal(real x)        { return __isnormall(x); }
+    extern(C) pragma(mangle, "__isnormall") pure int isnormal(real x);
 
     //int signbit(real-floating x);
     ///
-    pure int signbit(float x)        { return __signbitf(x); }
+    extern(C) pragma(mangle, "__signbitf") pure int signbit(float x);
     ///
-    pure int signbit(double x)       { return __signbit(x); }
+    extern(C) pragma(mangle, "__signbit")  pure int signbit(double x);
     ///
-    pure int signbit(real x)         { return __signbitl(x); }
+    extern(C) pragma(mangle, "__signbitl") pure int signbit(real x);
   }
 }
 
@@ -1841,14 +1766,12 @@ version (CRuntime_Microsoft) // fully supported since MSVCRT 12 (VS 2013) only
     ///
     extern(D) pure real  fabsl()(real x)  { return fabs(cast(double) x); }
 
-    private double _hypot(double x, double y);
-    private float  _hypotf(float x, float y);
     ///
-    extern(D) double hypot(double x, double y) { return _hypot(x, y); }
+    extern(C) pragma(mangle, "_hypot")  double hypot(double x, double y);
     ///
-    extern(D) float  hypotf(float x, float y)  { return _hypotf(x, y); }
+    extern(C) pragma(mangle, "_hypotf") float  hypotf(float x, float y);
     ///
-    extern(D) real   hypotl(real x, real y)    { return _hypot(cast(double) x, cast(double) y); }
+    extern(D) real   hypotl(real x, real y)    { return hypot(cast(double) x, cast(double) y); }
 
     ///
     double  pow(double x, double y);
diff --git a/libphobos/libdruntime/core/stdc/stdio.d b/libphobos/libdruntime/core/stdc/stdio.d
index 6701159..c76b922 100644
--- a/libphobos/libdruntime/core/stdc/stdio.d
+++ b/libphobos/libdruntime/core/stdc/stdio.d
@@ -1166,61 +1166,73 @@ version (MinGW)
     // Prefer the MinGW versions over the MSVC ones, as the latter don't handle
     // reals at all.
     ///
+    pragma(printf)
     int __mingw_fprintf(FILE* stream, scope const char* format, scope const ...);
     ///
     alias __mingw_fprintf fprintf;
 
     ///
+    pragma(scanf)
     int __mingw_fscanf(FILE* stream, scope const char* format, scope ...);
     ///
     alias __mingw_fscanf fscanf;
 
     ///
+    pragma(printf)
     int __mingw_sprintf(scope char* s, scope const char* format, scope const ...);
     ///
     alias __mingw_sprintf sprintf;
 
     ///
+    pragma(scanf)
     int __mingw_sscanf(scope const char* s, scope const char* format, scope ...);
     ///
     alias __mingw_sscanf sscanf;
 
     ///
+    pragma(printf)
     int __mingw_vfprintf(FILE* stream, scope const char* format, va_list arg);
     ///
     alias __mingw_vfprintf vfprintf;
 
     ///
+    pragma(scanf)
     int __mingw_vfscanf(FILE* stream, scope const char* format, va_list arg);
     ///
     alias __mingw_vfscanf vfscanf;
 
     ///
+    pragma(printf)
     int __mingw_vsprintf(scope char* s, scope const char* format, va_list arg);
     ///
     alias __mingw_vsprintf vsprintf;
 
     ///
+    pragma(scanf)
     int __mingw_vsscanf(scope const char* s, scope const char* format, va_list arg);
     ///
     alias __mingw_vsscanf vsscanf;
 
     ///
+    pragma(printf)
     int __mingw_vprintf(scope const char* format, va_list arg);
     ///
     alias __mingw_vprintf vprintf;
 
     ///
+    pragma(scanf)
     int __mingw_vscanf(scope const char* format, va_list arg);
     ///
     alias __mingw_vscanf vscanf;
 
     ///
+    pragma(printf)
     int __mingw_printf(scope const char* format, scope const ...);
     ///
     alias __mingw_printf printf;
 
     ///
+    pragma(scanf)
     int __mingw_scanf(scope const char* format, scope ...);
     ///
     alias __mingw_scanf scanf;
@@ -1228,28 +1240,40 @@ version (MinGW)
 else
 {
     ///
+    pragma(printf)
     int fprintf(FILE* stream, scope const char* format, scope const ...);
     ///
+    pragma(scanf)
     int fscanf(FILE* stream, scope const char* format, scope ...);
     ///
+    pragma(printf)
     int sprintf(scope char* s, scope const char* format, scope const ...);
     ///
+    pragma(scanf)
     int sscanf(scope const char* s, scope const char* format, scope ...);
     ///
+    pragma(printf)
     int vfprintf(FILE* stream, scope const char* format, va_list arg);
     ///
+    pragma(scanf)
     int vfscanf(FILE* stream, scope const char* format, va_list arg);
     ///
+    pragma(printf)
     int vsprintf(scope char* s, scope const char* format, va_list arg);
     ///
+    pragma(scanf)
     int vsscanf(scope const char* s, scope const char* format, va_list arg);
     ///
+    pragma(printf)
     int vprintf(scope const char* format, va_list arg);
     ///
+    pragma(scanf)
     int vscanf(scope const char* format, va_list arg);
     ///
+    pragma(printf)
     int printf(scope const char* format, scope const ...);
     ///
+    pragma(scanf)
     int scanf(scope const char* format, scope ...);
 }
 
@@ -1278,13 +1302,14 @@ extern (D) @trusted
     int getchar()()                 { return getc(stdin);     }
     ///
     int putchar()(int c)            { return putc(c,stdout);  }
-    ///
-    int getc()(FILE* stream)        { return fgetc(stream);   }
-    ///
-    int putc()(int c, FILE* stream) { return fputc(c,stream); }
 }
 
 ///
+alias getc = fgetc;
+///
+alias putc = fputc;
+
+///
 @trusted int ungetc(int c, FILE* stream); // No unsafe pointer manipulation.
 
 ///
@@ -1322,15 +1347,37 @@ version (CRuntime_DigitalMars)
     ///
     pure int  fileno()(FILE* stream)   { return stream._file; }
   }
-  ///
+    ///
+    pragma(printf)
     int   _snprintf(scope char* s, size_t n, scope const char* fmt, scope const ...);
     ///
     alias _snprintf snprintf;
 
     ///
+    pragma(printf)
     int   _vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
     ///
     alias _vsnprintf vsnprintf;
+
+    //
+    // Digital Mars under-the-hood C I/O functions. Uses _iobuf* for the
+    // unshared version of FILE*, usable when the FILE is locked.
+    //
+
+    ///
+    int _fputc_nlock(int c, _iobuf* fp);
+    ///
+    int _fputwc_nlock(int c, _iobuf* fp);
+    ///
+    int _fgetc_nlock(_iobuf* fp);
+    ///
+    int _fgetwc_nlock(_iobuf* fp);
+    ///
+    int __fp_lock(FILE* fp);
+    ///
+    void __fp_unlock(FILE* fp);
+    ///
+    int setmode(int fd, int mode);
 }
 else version (CRuntime_Microsoft)
 {
@@ -1351,6 +1398,7 @@ else version (CRuntime_Microsoft)
 
   version (MinGW)
   {
+    pragma(printf)
     int   __mingw_snprintf(scope char* s, size_t n, scope const char* fmt, scope const ...);
     ///
     alias __mingw_snprintf _snprintf;
@@ -1358,6 +1406,7 @@ else version (CRuntime_Microsoft)
     alias __mingw_snprintf snprintf;
 
     ///
+    pragma(printf)
     int   __mingw_vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
     ///
     alias __mingw_vsnprintf _vsnprintf;
@@ -1367,26 +1416,45 @@ else version (CRuntime_Microsoft)
   else
   {
     ///
+    pragma(printf)
     int _snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
 
     ///
+    pragma(printf)
     int _vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
   }
 
+    //
+    // Microsoft under-the-hood C I/O functions. Uses _iobuf* for the unshared
+    // version of FILE*, usable when the FILE is locked.
+    //
+    import core.stdc.stddef : wchar_t;
+    import core.stdc.wchar_ : wint_t;
+
     ///
-    int _fputc_nolock(int c, FILE *fp);
+    int _fputc_nolock(int c, _iobuf* fp);
     ///
-    int _fgetc_nolock(FILE *fp);
-
+    int _fgetc_nolock(_iobuf* fp);
     ///
-    int _lock_file(FILE *fp);
+    wint_t _fputwc_nolock(wchar_t c, _iobuf* fp);
     ///
-    int _unlock_file(FILE *fp);
-
+    wint_t _fgetwc_nolock(_iobuf* fp);
+    ///
+    void _lock_file(FILE* fp);
+    ///
+    void _unlock_file(FILE* fp);
+    ///
+    int _setmode(int fd, int mode);
+    ///
+    int _fseeki64(FILE* stream, long offset, int origin);
+    ///
+    long _ftelli64(FILE* stream);
     ///
     intptr_t _get_osfhandle(int fd);
     ///
@@ -1410,9 +1478,28 @@ else version (CRuntime_Glibc)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
+
+    //
+    // Gnu under-the-hood C I/O functions. Uses _iobuf* for the unshared
+    // version of FILE*, usable when the FILE is locked.
+    // See http://gnu.org/software/libc/manual/html_node/I_002fO-on-Streams.html
+    //
+    import core.stdc.wchar_ : wint_t;
+    import core.stdc.stddef : wchar_t;
+
+    ///
+    int fputc_unlocked(int c, _iobuf* stream);
+    ///
+    int fgetc_unlocked(_iobuf* stream);
+    ///
+    wint_t fputwc_unlocked(wchar_t wc, _iobuf* stream);
+    ///
+    wint_t fgetwc_unlocked(_iobuf* stream);
 }
 else version (Darwin)
 {
@@ -1432,8 +1519,10 @@ else version (Darwin)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (FreeBSD)
@@ -1454,8 +1543,10 @@ else version (FreeBSD)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (NetBSD)
@@ -1476,8 +1567,10 @@ else version (NetBSD)
   }
 
     ///
+    pragma(printf)
     int  snprintf(char* s, size_t n, const scope char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(char* s, size_t n, const scope char* format, va_list arg);
 }
 else version (OpenBSD)
@@ -1567,8 +1660,10 @@ else version (OpenBSD)
     }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (DragonFlyBSD)
@@ -1599,7 +1694,9 @@ else version (DragonFlyBSD)
   enum __SALC = 0x4000;
   enum __SIGN = 0x8000;
 
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (Solaris)
@@ -1620,8 +1717,10 @@ else version (Solaris)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (CRuntime_Bionic)
@@ -1642,8 +1741,10 @@ else version (CRuntime_Bionic)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (CRuntime_Musl)
@@ -1663,8 +1764,10 @@ else version (CRuntime_Musl)
     }
 
     ///
+    pragma(printf)
     int snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else version (CRuntime_UClibc)
@@ -1685,8 +1788,10 @@ else version (CRuntime_UClibc)
   }
 
     ///
+    pragma(printf)
     int  snprintf(scope char* s, size_t n, scope const char* format, scope const ...);
     ///
+    pragma(printf)
     int  vsnprintf(scope char* s, size_t n, scope const char* format, va_list arg);
 }
 else
@@ -1854,6 +1959,22 @@ version (Windows)
         O_TEXT = _O_TEXT, ///
         _O_BINARY = 0x8000, ///
         O_BINARY = _O_BINARY, ///
+        _O_WTEXT = 0x10000, ///
+        _O_U16TEXT = 0x20000, ///
+        _O_U8TEXT = 0x40000, ///
+        _O_ACCMODE = (_O_RDONLY|_O_WRONLY|_O_RDWR), ///
+        O_ACCMODE = _O_ACCMODE, ///
+        _O_RAW = _O_BINARY, ///
+        O_RAW = _O_BINARY, ///
+        _O_NOINHERIT = 0x0080, ///
+        O_NOINHERIT = _O_NOINHERIT, ///
+        _O_TEMPORARY = 0x0040, ///
+        O_TEMPORARY = _O_TEMPORARY, ///
+        _O_SHORT_LIVED = 0x1000, ///
+        _O_SEQUENTIAL = 0x0020, ///
+        O_SEQUENTIAL = _O_SEQUENTIAL, ///
+        _O_RANDOM = 0x0010, ///
+        O_RANDOM = _O_RANDOM, ///
     }
 
     enum
diff --git a/libphobos/libdruntime/core/stdc/stdlib.d b/libphobos/libdruntime/core/stdc/stdlib.d
index 7caef4c..35e81a2 100644
--- a/libphobos/libdruntime/core/stdc/stdlib.d
+++ b/libphobos/libdruntime/core/stdc/stdlib.d
@@ -121,19 +121,22 @@ ulong   strtoull(scope inout(char)* nptr, scope inout(char)** endptr, int base);
 
 version (CRuntime_Microsoft)
 {
-    // strtold exists starting from VS2013, so we give it D linkage to avoid link errors
-    ///
-    extern (D) real strtold(scope inout(char)* nptr, inout(char)** endptr)
-    {   // Fake it 'till we make it
-        return strtod(nptr, endptr);
+    version (MinGW)
+    {
+        ///
+        real __mingw_strtold(scope inout(char)* nptr, scope inout(char)** endptr);
+        ///
+        alias __mingw_strtold strtold;
+    }
+    else
+    {
+        // strtold exists starting from VS2013, so we give it D linkage to avoid link errors
+        ///
+        extern (D) real strtold(scope inout(char)* nptr, inout(char)** endptr)
+        {   // Fake it 'till we make it
+            return strtod(nptr, endptr);
+        }
     }
-}
-else version (MinGW)
-{
-    ///
-    real __mingw_strtold(scope inout(char)* nptr, scope inout(char)** endptr);
-    ///
-    alias __mingw_strtold strtold;
 }
 else
 {
@@ -164,13 +167,13 @@ void*   realloc(void* ptr, size_t size);
 void    free(void* ptr);
 
 ///
-void    abort() @safe;
+noreturn abort() @safe;
 ///
-void    exit(int status);
+noreturn exit(int status);
 ///
 int     atexit(void function() func);
 ///
-void    _Exit(int status);
+noreturn _Exit(int status);
 
 ///
 char*   getenv(scope const char* name);
diff --git a/libphobos/libdruntime/core/stdc/tgmath.d b/libphobos/libdruntime/core/stdc/tgmath.d
index 4dd1b3c..2d1a198 100644
--- a/libphobos/libdruntime/core/stdc/tgmath.d
+++ b/libphobos/libdruntime/core/stdc/tgmath.d
@@ -32,12 +32,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.acosl         acos;
 
-    ///
-    alias core.stdc.complex.cacos      acos;
-    ///
-    alias core.stdc.complex.cacosf     acos;
-    ///
-    alias core.stdc.complex.cacosl     acos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacos      acos;
+    deprecated alias core.stdc.complex.cacosf     acos;
+    deprecated alias core.stdc.complex.cacosl     acos;
 
     ///
     alias core.stdc.math.asin          asin;
@@ -46,12 +44,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.asinl         asin;
 
-    ///
-    alias core.stdc.complex.casin      asin;
-    ///
-    alias core.stdc.complex.casinf     asin;
-    ///
-    alias core.stdc.complex.casinl     asin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casin      asin;
+    deprecated alias core.stdc.complex.casinf     asin;
+    deprecated alias core.stdc.complex.casinl     asin;
 
     ///
     alias core.stdc.math.atan          atan;
@@ -60,12 +56,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.atanl         atan;
 
-    ///
-    alias core.stdc.complex.catan      atan;
-    ///
-    alias core.stdc.complex.catanf     atan;
-    ///
-    alias core.stdc.complex.catanl     atan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catan      atan;
+    deprecated alias core.stdc.complex.catanf     atan;
+    deprecated alias core.stdc.complex.catanl     atan;
 
     ///
     alias core.stdc.math.atan2         atan2;
@@ -81,12 +75,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.cosl          cos;
 
-    ///
-    alias core.stdc.complex.ccos       cos;
-    ///
-    alias core.stdc.complex.ccosf      cos;
-    ///
-    alias core.stdc.complex.ccosl      cos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccos       cos;
+    deprecated alias core.stdc.complex.ccosf      cos;
+    deprecated alias core.stdc.complex.ccosl      cos;
 
     ///
     alias core.stdc.math.sin           sin;
@@ -95,12 +87,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.sinl          sin;
 
-    ///
-    alias core.stdc.complex.csin       csin;
-    ///
-    alias core.stdc.complex.csinf      csin;
-    ///
-    alias core.stdc.complex.csinl      csin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csin       csin;
+    deprecated alias core.stdc.complex.csinf      csin;
+    deprecated alias core.stdc.complex.csinl      csin;
 
     ///
     alias core.stdc.math.tan           tan;
@@ -109,12 +99,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.tanl          tan;
 
-    ///
-    alias core.stdc.complex.ctan       tan;
-    ///
-    alias core.stdc.complex.ctanf      tan;
-    ///
-    alias core.stdc.complex.ctanl      tan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctan       tan;
+    deprecated alias core.stdc.complex.ctanf      tan;
+    deprecated alias core.stdc.complex.ctanl      tan;
 
     ///
     alias core.stdc.math.acosh         acosh;
@@ -123,12 +111,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.acoshl        acosh;
 
-    ///
-    alias core.stdc.complex.cacosh     acosh;
-    ///
-    alias core.stdc.complex.cacoshf    acosh;
-    ///
-    alias core.stdc.complex.cacoshl    acosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacosh     acosh;
+    deprecated alias core.stdc.complex.cacoshf    acosh;
+    deprecated alias core.stdc.complex.cacoshl    acosh;
 
     ///
     alias core.stdc.math.asinh         asinh;
@@ -137,12 +123,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.asinhl        asinh;
 
-    ///
-    alias core.stdc.complex.casinh     asinh;
-    ///
-    alias core.stdc.complex.casinhf    asinh;
-    ///
-    alias core.stdc.complex.casinhl    asinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casinh     asinh;
+    deprecated alias core.stdc.complex.casinhf    asinh;
+    deprecated alias core.stdc.complex.casinhl    asinh;
 
     ///
     alias core.stdc.math.atanh         atanh;
@@ -151,12 +135,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.atanhl        atanh;
 
-    ///
-    alias core.stdc.complex.catanh     atanh;
-    ///
-    alias core.stdc.complex.catanhf    atanh;
-    ///
-    alias core.stdc.complex.catanhl    atanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catanh     atanh;
+    deprecated alias core.stdc.complex.catanhf    atanh;
+    deprecated alias core.stdc.complex.catanhl    atanh;
 
     ///
     alias core.stdc.math.cosh          cosh;
@@ -165,12 +147,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.coshl         cosh;
 
-    ///
-    alias core.stdc.complex.ccosh      cosh;
-    ///
-    alias core.stdc.complex.ccoshf     cosh;
-    ///
-    alias core.stdc.complex.ccoshl     cosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccosh      cosh;
+    deprecated alias core.stdc.complex.ccoshf     cosh;
+    deprecated alias core.stdc.complex.ccoshl     cosh;
 
     ///
     alias core.stdc.math.sinh          sinh;
@@ -179,12 +159,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.sinhl         sinh;
 
-    ///
-    alias core.stdc.complex.csinh      sinh;
-    ///
-    alias core.stdc.complex.csinhf     sinh;
-    ///
-    alias core.stdc.complex.csinhl     sinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csinh      sinh;
+    deprecated alias core.stdc.complex.csinhf     sinh;
+    deprecated alias core.stdc.complex.csinhl     sinh;
 
     ///
     alias core.stdc.math.tanh          tanh;
@@ -193,12 +171,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.tanhl         tanh;
 
-    ///
-    alias core.stdc.complex.ctanh      tanh;
-    ///
-    alias core.stdc.complex.ctanhf     tanh;
-    ///
-    alias core.stdc.complex.ctanhl     tanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctanh      tanh;
+    deprecated alias core.stdc.complex.ctanhf     tanh;
+    deprecated alias core.stdc.complex.ctanhl     tanh;
 
     ///
     alias core.stdc.math.exp           exp;
@@ -207,12 +183,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.expl          exp;
 
-    ///
-    alias core.stdc.complex.cexp       exp;
-    ///
-    alias core.stdc.complex.cexpf      exp;
-    ///
-    alias core.stdc.complex.cexpl      exp;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cexp       exp;
+    deprecated alias core.stdc.complex.cexpf      exp;
+    deprecated alias core.stdc.complex.cexpl      exp;
 
     ///
     alias core.stdc.math.exp2          exp2;
@@ -256,12 +230,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.logl          log;
 
-    ///
-    alias core.stdc.complex.clog       log;
-    ///
-    alias core.stdc.complex.clogf      log;
-    ///
-    alias core.stdc.complex.clogl      log;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.clog       log;
+    deprecated alias core.stdc.complex.clogf      log;
+    deprecated alias core.stdc.complex.clogl      log;
 
     ///
     alias core.stdc.math.log10         log10;
@@ -325,12 +297,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.fabsl         fabs;
 
-    ///
-    alias core.stdc.complex.cabs       fabs;
-    ///
-    alias core.stdc.complex.cabsf      fabs;
-    ///
-    alias core.stdc.complex.cabsl      fabs;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cabs       fabs;
+    deprecated alias core.stdc.complex.cabsf      fabs;
+    deprecated alias core.stdc.complex.cabsl      fabs;
 
     ///
     alias core.stdc.math.hypot         hypot;
@@ -346,12 +316,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.powl          pow;
 
-    ///
-    alias core.stdc.complex.cpow       pow;
-    ///
-    alias core.stdc.complex.cpowf      pow;
-    ///
-    alias core.stdc.complex.cpowl      pow;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cpow       pow;
+    deprecated alias core.stdc.complex.cpowf      pow;
+    deprecated alias core.stdc.complex.cpowl      pow;
 
     ///
     alias core.stdc.math.sqrt          sqrt;
@@ -360,12 +328,10 @@ version (NetBSD)
     ///
     alias core.stdc.math.sqrtl         sqrt;
 
-    ///
-    alias core.stdc.complex.csqrt      sqrt;
-    ///
-    alias core.stdc.complex.csqrtf     sqrt;
-    ///
-    alias core.stdc.complex.csqrtl     sqrt;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csqrt      sqrt;
+    deprecated alias core.stdc.complex.csqrtf     sqrt;
+    deprecated alias core.stdc.complex.csqrtl     sqrt;
 
     ///
     alias core.stdc.math.erf           erf;
@@ -539,37 +505,23 @@ version (NetBSD)
     ///
     alias core.stdc.math.fmal          fma;
 
-    ///
-    alias core.stdc.complex.carg       carg;
-    ///
-    alias core.stdc.complex.cargf      carg;
-    ///
-    alias core.stdc.complex.cargl      carg;
-
-    ///
-    alias core.stdc.complex.cimag      cimag;
-    ///
-    alias core.stdc.complex.cimagf     cimag;
-    ///
-    alias core.stdc.complex.cimagl     cimag;
-
-    ///
-    alias core.stdc.complex.conj       conj;
-    ///
-    alias core.stdc.complex.conjf      conj;
-    ///
-    alias core.stdc.complex.conjl      conj;
-
-    ///
-    alias core.stdc.complex.cproj      cproj;
-    ///
-    alias core.stdc.complex.cprojf     cproj;
-    ///
-    alias core.stdc.complex.cprojl     cproj;
-
-//  alias core.stdc.complex.creal      creal;
-//  alias core.stdc.complex.crealf     creal;
-//  alias core.stdc.complex.creall     creal;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.carg       carg;
+    deprecated alias core.stdc.complex.cargf      carg;
+    deprecated alias core.stdc.complex.cargl      carg;
+    deprecated alias core.stdc.complex.cimag      cimag;
+    deprecated alias core.stdc.complex.cimagf     cimag;
+    deprecated alias core.stdc.complex.cimagl     cimag;
+    deprecated alias core.stdc.complex.conj       conj;
+    deprecated alias core.stdc.complex.conjf      conj;
+    deprecated alias core.stdc.complex.conjl      conj;
+    deprecated alias core.stdc.complex.cproj      cproj;
+    deprecated alias core.stdc.complex.cprojf     cproj;
+    deprecated alias core.stdc.complex.cprojl     cproj;
+
+//  deprecated alias core.stdc.complex.creal      creal;
+//  deprecated alias core.stdc.complex.crealf     creal;
+//  deprecated alias core.stdc.complex.creall     creal;
 }
 else version (OpenBSD)
 {
@@ -580,12 +532,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.acosl         acos;
 
-    ///
-    alias core.stdc.complex.cacos      acos;
-    ///
-    alias core.stdc.complex.cacosf     acos;
-    ///
-    alias core.stdc.complex.cacosl     acos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacos      acos;
+    deprecated alias core.stdc.complex.cacosf     acos;
+    deprecated alias core.stdc.complex.cacosl     acos;
 
     ///
     alias core.stdc.math.asin          asin;
@@ -594,12 +544,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.asinl         asin;
 
-    ///
-    alias core.stdc.complex.casin      asin;
-    ///
-    alias core.stdc.complex.casinf     asin;
-    ///
-    alias core.stdc.complex.casinl     asin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casin      asin;
+    deprecated alias core.stdc.complex.casinf     asin;
+    deprecated alias core.stdc.complex.casinl     asin;
 
     ///
     alias core.stdc.math.atan          atan;
@@ -608,12 +556,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.atanl         atan;
 
-    ///
-    alias core.stdc.complex.catan      atan;
-    ///
-    alias core.stdc.complex.catanf     atan;
-    ///
-    alias core.stdc.complex.catanl     atan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catan      atan;
+    deprecated alias core.stdc.complex.catanf     atan;
+    deprecated alias core.stdc.complex.catanl     atan;
 
     ///
     alias core.stdc.math.atan2         atan2;
@@ -629,12 +575,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.cosl          cos;
 
-    ///
-    alias core.stdc.complex.ccos       cos;
-    ///
-    alias core.stdc.complex.ccosf      cos;
-    ///
-    alias core.stdc.complex.ccosl      cos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccos       cos;
+    deprecated alias core.stdc.complex.ccosf      cos;
+    deprecated alias core.stdc.complex.ccosl      cos;
 
     ///
     alias core.stdc.math.sin           sin;
@@ -643,12 +587,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.sinl          sin;
 
-    ///
-    alias core.stdc.complex.csin       csin;
-    ///
-    alias core.stdc.complex.csinf      csin;
-    ///
-    alias core.stdc.complex.csinl      csin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csin       csin;
+    deprecated alias core.stdc.complex.csinf      csin;
+    deprecated alias core.stdc.complex.csinl      csin;
 
     ///
     alias core.stdc.math.tan           tan;
@@ -657,12 +599,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.tanl          tan;
 
-    ///
-    alias core.stdc.complex.ctan       tan;
-    ///
-    alias core.stdc.complex.ctanf      tan;
-    ///
-    alias core.stdc.complex.ctanl      tan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctan       tan;
+    deprecated alias core.stdc.complex.ctanf      tan;
+    deprecated alias core.stdc.complex.ctanl      tan;
 
     ///
     alias core.stdc.math.acosh         acosh;
@@ -671,12 +611,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.acoshl        acosh;
 
-    ///
-    alias core.stdc.complex.cacosh     acosh;
-    ///
-    alias core.stdc.complex.cacoshf    acosh;
-    ///
-    alias core.stdc.complex.cacoshl    acosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacosh     acosh;
+    deprecated alias core.stdc.complex.cacoshf    acosh;
+    deprecated alias core.stdc.complex.cacoshl    acosh;
 
     ///
     alias core.stdc.math.asinh         asinh;
@@ -685,12 +623,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.asinhl        asinh;
 
-    ///
-    alias core.stdc.complex.casinh     asinh;
-    ///
-    alias core.stdc.complex.casinhf    asinh;
-    ///
-    alias core.stdc.complex.casinhl    asinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casinh     asinh;
+    deprecated alias core.stdc.complex.casinhf    asinh;
+    deprecated alias core.stdc.complex.casinhl    asinh;
 
     ///
     alias core.stdc.math.atanh         atanh;
@@ -699,12 +635,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.atanhl        atanh;
 
-    ///
-    alias core.stdc.complex.catanh     atanh;
-    ///
-    alias core.stdc.complex.catanhf    atanh;
-    ///
-    alias core.stdc.complex.catanhl    atanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catanh     atanh;
+    deprecated alias core.stdc.complex.catanhf    atanh;
+    deprecated alias core.stdc.complex.catanhl    atanh;
 
     ///
     alias core.stdc.math.cosh          cosh;
@@ -713,12 +647,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.coshl         cosh;
 
-    ///
-    alias core.stdc.complex.ccosh      cosh;
-    ///
-    alias core.stdc.complex.ccoshf     cosh;
-    ///
-    alias core.stdc.complex.ccoshl     cosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccosh      cosh;
+    deprecated alias core.stdc.complex.ccoshf     cosh;
+    deprecated alias core.stdc.complex.ccoshl     cosh;
 
     ///
     alias core.stdc.math.sinh          sinh;
@@ -727,12 +659,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.sinhl         sinh;
 
-    ///
-    alias core.stdc.complex.csinh      sinh;
-    ///
-    alias core.stdc.complex.csinhf     sinh;
-    ///
-    alias core.stdc.complex.csinhl     sinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csinh      sinh;
+    deprecated alias core.stdc.complex.csinhf     sinh;
+    deprecated alias core.stdc.complex.csinhl     sinh;
 
     ///
     alias core.stdc.math.tanh          tanh;
@@ -741,12 +671,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.tanhl         tanh;
 
-    ///
-    alias core.stdc.complex.ctanh      tanh;
-    ///
-    alias core.stdc.complex.ctanhf     tanh;
-    ///
-    alias core.stdc.complex.ctanhl     tanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctanh      tanh;
+    deprecated alias core.stdc.complex.ctanhf     tanh;
+    deprecated alias core.stdc.complex.ctanhl     tanh;
 
     ///
     alias core.stdc.math.exp           exp;
@@ -755,12 +683,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.expl          exp;
 
-    ///
-    alias core.stdc.complex.cexp       exp;
-    ///
-    alias core.stdc.complex.cexpf      exp;
-    ///
-    alias core.stdc.complex.cexpl      exp;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cexp       exp;
+    deprecated alias core.stdc.complex.cexpf      exp;
+    deprecated alias core.stdc.complex.cexpl      exp;
 
     ///
     alias core.stdc.math.exp2          exp2;
@@ -804,12 +730,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.logl          log;
 
-    ///
-    alias core.stdc.complex.clog       log;
-    ///
-    alias core.stdc.complex.clogf      log;
-    ///
-    alias core.stdc.complex.clogl      log;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.clog       log;
+    deprecated alias core.stdc.complex.clogf      log;
+    deprecated alias core.stdc.complex.clogl      log;
 
     ///
     alias core.stdc.math.log10         log10;
@@ -874,12 +798,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.fabsl         fabs;
 
-    ///
-    alias core.stdc.complex.cabs       fabs;
-    ///
-    alias core.stdc.complex.cabsf      fabs;
-    ///
-    alias core.stdc.complex.cabsl      fabs;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cabs       fabs;
+    deprecated alias core.stdc.complex.cabsf      fabs;
+    deprecated alias core.stdc.complex.cabsl      fabs;
 
     ///
     alias core.stdc.math.hypot         hypot;
@@ -895,12 +817,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.powl          pow;
 
-    ///
-    alias core.stdc.complex.cpow       pow;
-    ///
-    alias core.stdc.complex.cpowf      pow;
-    ///
-    alias core.stdc.complex.cpowl      pow;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cpow       pow;
+    deprecated alias core.stdc.complex.cpowf      pow;
+    deprecated alias core.stdc.complex.cpowl      pow;
 
     ///
     alias core.stdc.math.sqrt          sqrt;
@@ -909,12 +829,10 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.sqrtl         sqrt;
 
-    ///
-    alias core.stdc.complex.csqrt      sqrt;
-    ///
-    alias core.stdc.complex.csqrtf     sqrt;
-    ///
-    alias core.stdc.complex.csqrtl     sqrt;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csqrt      sqrt;
+    deprecated alias core.stdc.complex.csqrtf     sqrt;
+    deprecated alias core.stdc.complex.csqrtl     sqrt;
 
     ///
     alias core.stdc.math.erf           erf;
@@ -1077,37 +995,23 @@ else version (OpenBSD)
     ///
     alias core.stdc.math.fmal          fma;
 
-    ///
-    alias core.stdc.complex.carg       carg;
-    ///
-    alias core.stdc.complex.cargf      carg;
-    ///
-    alias core.stdc.complex.cargl      carg;
-
-    ///
-    alias core.stdc.complex.cimag      cimag;
-    ///
-    alias core.stdc.complex.cimagf     cimag;
-    ///
-    alias core.stdc.complex.cimagl     cimag;
-
-    ///
-    alias core.stdc.complex.conj       conj;
-    ///
-    alias core.stdc.complex.conjf      conj;
-    ///
-    alias core.stdc.complex.conjl      conj;
-
-    ///
-    alias core.stdc.complex.cproj      cproj;
-    ///
-    alias core.stdc.complex.cprojf     cproj;
-    ///
-    alias core.stdc.complex.cprojl     cproj;
-
-//  alias core.stdc.complex.creal      creal;
-//  alias core.stdc.complex.crealf     creal;
-//  alias core.stdc.complex.creall     creal;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.carg       carg;
+    deprecated alias core.stdc.complex.cargf      carg;
+    deprecated alias core.stdc.complex.cargl      carg;
+    deprecated alias core.stdc.complex.cimag      cimag;
+    deprecated alias core.stdc.complex.cimagf     cimag;
+    deprecated alias core.stdc.complex.cimagl     cimag;
+    deprecated alias core.stdc.complex.conj       conj;
+    deprecated alias core.stdc.complex.conjf      conj;
+    deprecated alias core.stdc.complex.conjl      conj;
+    deprecated alias core.stdc.complex.cproj      cproj;
+    deprecated alias core.stdc.complex.cprojf     cproj;
+    deprecated alias core.stdc.complex.cprojl     cproj;
+
+//  deprecated alias core.stdc.complex.creal      creal;
+//  deprecated alias core.stdc.complex.crealf     creal;
+//  deprecated alias core.stdc.complex.creall     creal;
 }
 else
 {
@@ -1118,12 +1022,10 @@ else
     ///
     alias core.stdc.math.acosl         acos;
 
-    ///
-    alias core.stdc.complex.cacos      acos;
-    ///
-    alias core.stdc.complex.cacosf     acos;
-    ///
-    alias core.stdc.complex.cacosl     acos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacos      acos;
+    deprecated alias core.stdc.complex.cacosf     acos;
+    deprecated alias core.stdc.complex.cacosl     acos;
 
     ///
     alias core.stdc.math.asin          asin;
@@ -1132,12 +1034,10 @@ else
     ///
     alias core.stdc.math.asinl         asin;
 
-    ///
-    alias core.stdc.complex.casin      asin;
-    ///
-    alias core.stdc.complex.casinf     asin;
-    ///
-    alias core.stdc.complex.casinl     asin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casin      asin;
+    deprecated alias core.stdc.complex.casinf     asin;
+    deprecated alias core.stdc.complex.casinl     asin;
 
     ///
     alias core.stdc.math.atan          atan;
@@ -1146,12 +1046,10 @@ else
     ///
     alias core.stdc.math.atanl         atan;
 
-    ///
-    alias core.stdc.complex.catan      atan;
-    ///
-    alias core.stdc.complex.catanf     atan;
-    ///
-    alias core.stdc.complex.catanl     atan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catan      atan;
+    deprecated alias core.stdc.complex.catanf     atan;
+    deprecated alias core.stdc.complex.catanl     atan;
 
     ///
     alias core.stdc.math.atan2         atan2;
@@ -1167,12 +1065,10 @@ else
     ///
     alias core.stdc.math.cosl          cos;
 
-    ///
-    alias core.stdc.complex.ccos       cos;
-    ///
-    alias core.stdc.complex.ccosf      cos;
-    ///
-    alias core.stdc.complex.ccosl      cos;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccos       cos;
+    deprecated alias core.stdc.complex.ccosf      cos;
+    deprecated alias core.stdc.complex.ccosl      cos;
 
     ///
     alias core.stdc.math.sin           sin;
@@ -1181,12 +1077,10 @@ else
     ///
     alias core.stdc.math.sinl          sin;
 
-    ///
-    alias core.stdc.complex.csin       csin;
-    ///
-    alias core.stdc.complex.csinf      csin;
-    ///
-    alias core.stdc.complex.csinl      csin;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csin       csin;
+    deprecated alias core.stdc.complex.csinf      csin;
+    deprecated alias core.stdc.complex.csinl      csin;
 
     ///
     alias core.stdc.math.tan           tan;
@@ -1195,12 +1089,10 @@ else
     ///
     alias core.stdc.math.tanl          tan;
 
-    ///
-    alias core.stdc.complex.ctan       tan;
-    ///
-    alias core.stdc.complex.ctanf      tan;
-    ///
-    alias core.stdc.complex.ctanl      tan;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctan       tan;
+    deprecated alias core.stdc.complex.ctanf      tan;
+    deprecated alias core.stdc.complex.ctanl      tan;
 
     ///
     alias core.stdc.math.acosh         acosh;
@@ -1209,12 +1101,10 @@ else
     ///
     alias core.stdc.math.acoshl        acosh;
 
-    ///
-    alias core.stdc.complex.cacosh     acosh;
-    ///
-    alias core.stdc.complex.cacoshf    acosh;
-    ///
-    alias core.stdc.complex.cacoshl    acosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cacosh     acosh;
+    deprecated alias core.stdc.complex.cacoshf    acosh;
+    deprecated alias core.stdc.complex.cacoshl    acosh;
 
     ///
     alias core.stdc.math.asinh         asinh;
@@ -1223,12 +1113,10 @@ else
     ///
     alias core.stdc.math.asinhl        asinh;
 
-    ///
-    alias core.stdc.complex.casinh     asinh;
-    ///
-    alias core.stdc.complex.casinhf    asinh;
-    ///
-    alias core.stdc.complex.casinhl    asinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.casinh     asinh;
+    deprecated alias core.stdc.complex.casinhf    asinh;
+    deprecated alias core.stdc.complex.casinhl    asinh;
 
     ///
     alias core.stdc.math.atanh         atanh;
@@ -1237,12 +1125,10 @@ else
     ///
     alias core.stdc.math.atanhl        atanh;
 
-    ///
-    alias core.stdc.complex.catanh     atanh;
-    ///
-    alias core.stdc.complex.catanhf    atanh;
-    ///
-    alias core.stdc.complex.catanhl    atanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.catanh     atanh;
+    deprecated alias core.stdc.complex.catanhf    atanh;
+    deprecated alias core.stdc.complex.catanhl    atanh;
 
     ///
     alias core.stdc.math.cosh          cosh;
@@ -1251,12 +1137,10 @@ else
     ///
     alias core.stdc.math.coshl         cosh;
 
-    ///
-    alias core.stdc.complex.ccosh      cosh;
-    ///
-    alias core.stdc.complex.ccoshf     cosh;
-    ///
-    alias core.stdc.complex.ccoshl     cosh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ccosh      cosh;
+    deprecated alias core.stdc.complex.ccoshf     cosh;
+    deprecated alias core.stdc.complex.ccoshl     cosh;
 
     ///
     alias core.stdc.math.sinh          sinh;
@@ -1265,12 +1149,10 @@ else
     ///
     alias core.stdc.math.sinhl         sinh;
 
-    ///
-    alias core.stdc.complex.csinh      sinh;
-    ///
-    alias core.stdc.complex.csinhf     sinh;
-    ///
-    alias core.stdc.complex.csinhl     sinh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csinh      sinh;
+    deprecated alias core.stdc.complex.csinhf     sinh;
+    deprecated alias core.stdc.complex.csinhl     sinh;
 
     ///
     alias core.stdc.math.tanh          tanh;
@@ -1279,12 +1161,10 @@ else
     ///
     alias core.stdc.math.tanhl         tanh;
 
-    ///
-    alias core.stdc.complex.ctanh      tanh;
-    ///
-    alias core.stdc.complex.ctanhf     tanh;
-    ///
-    alias core.stdc.complex.ctanhl     tanh;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.ctanh      tanh;
+    deprecated alias core.stdc.complex.ctanhf     tanh;
+    deprecated alias core.stdc.complex.ctanhl     tanh;
 
     ///
     alias core.stdc.math.exp           exp;
@@ -1293,12 +1173,10 @@ else
     ///
     alias core.stdc.math.expl          exp;
 
-    ///
-    alias core.stdc.complex.cexp       exp;
-    ///
-    alias core.stdc.complex.cexpf      exp;
-    ///
-    alias core.stdc.complex.cexpl      exp;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cexp       exp;
+    deprecated alias core.stdc.complex.cexpf      exp;
+    deprecated alias core.stdc.complex.cexpl      exp;
 
     ///
     alias core.stdc.math.exp2          exp2;
@@ -1342,12 +1220,10 @@ else
     ///
     alias core.stdc.math.logl          log;
 
-    ///
-    alias core.stdc.complex.clog       log;
-    ///
-    alias core.stdc.complex.clogf      log;
-    ///
-    alias core.stdc.complex.clogl      log;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.clog       log;
+    deprecated alias core.stdc.complex.clogf      log;
+    deprecated alias core.stdc.complex.clogl      log;
 
     ///
     alias core.stdc.math.log10         log10;
@@ -1409,6 +1285,13 @@ else
     alias core.stdc.math.fabs          fabs;
     version (CRuntime_Microsoft)
     {
+        version (MinGW)
+        {
+            ///
+            alias core.stdc.math.fabsf     fabs;
+            ///
+            alias core.stdc.math.fabsl     fabs;
+        }
     }
     else
     {
@@ -1418,12 +1301,10 @@ else
         alias core.stdc.math.fabsl         fabs;
     }
 
-    ///
-    alias core.stdc.complex.cabs       fabs;
-    ///
-    alias core.stdc.complex.cabsf      fabs;
-    ///
-    alias core.stdc.complex.cabsl      fabs;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cabs       fabs;
+    deprecated alias core.stdc.complex.cabsf      fabs;
+    deprecated alias core.stdc.complex.cabsl      fabs;
 
     ///
     alias core.stdc.math.hypot         hypot;
@@ -1439,12 +1320,10 @@ else
     ///
     alias core.stdc.math.powl          pow;
 
-    ///
-    alias core.stdc.complex.cpow       pow;
-    ///
-    alias core.stdc.complex.cpowf      pow;
-    ///
-    alias core.stdc.complex.cpowl      pow;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.cpow       pow;
+    deprecated alias core.stdc.complex.cpowf      pow;
+    deprecated alias core.stdc.complex.cpowl      pow;
 
     ///
     alias core.stdc.math.sqrt          sqrt;
@@ -1453,12 +1332,10 @@ else
     ///
     alias core.stdc.math.sqrtl         sqrt;
 
-    ///
-    alias core.stdc.complex.csqrt      sqrt;
-    ///
-    alias core.stdc.complex.csqrtf     sqrt;
-    ///
-    alias core.stdc.complex.csqrtl     sqrt;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.csqrt      sqrt;
+    deprecated alias core.stdc.complex.csqrtf     sqrt;
+    deprecated alias core.stdc.complex.csqrtl     sqrt;
 
     ///
     alias core.stdc.math.erf           erf;
@@ -1635,35 +1512,20 @@ else
     ///
     alias core.stdc.math.fmal          fma;
 
-    ///
-    alias core.stdc.complex.carg       carg;
-    ///
-    alias core.stdc.complex.cargf      carg;
-    ///
-    alias core.stdc.complex.cargl      carg;
-
-    ///
-    alias core.stdc.complex.cimag      cimag;
-    ///
-    alias core.stdc.complex.cimagf     cimag;
-    ///
-    alias core.stdc.complex.cimagl     cimag;
-
-    ///
-    alias core.stdc.complex.conj       conj;
-    ///
-    alias core.stdc.complex.conjf      conj;
-    ///
-    alias core.stdc.complex.conjl      conj;
-
-    ///
-    alias core.stdc.complex.cproj      cproj;
-    ///
-    alias core.stdc.complex.cprojf     cproj;
-    ///
-    alias core.stdc.complex.cprojl     cproj;
-
-//  alias core.stdc.complex.creal      creal;
-//  alias core.stdc.complex.crealf     creal;
-//  alias core.stdc.complex.creall     creal;
+    // @@@DEPRECATED_2.105@@@
+    deprecated alias core.stdc.complex.carg       carg;
+    deprecated alias core.stdc.complex.cargf      carg;
+    deprecated alias core.stdc.complex.cargl      carg;
+    deprecated alias core.stdc.complex.cimag      cimag;
+    deprecated alias core.stdc.complex.cimagf     cimag;
+    deprecated alias core.stdc.complex.cimagl     cimag;
+    deprecated alias core.stdc.complex.conj       conj;
+    deprecated alias core.stdc.complex.conjf      conj;
+    deprecated alias core.stdc.complex.conjl      conj;
+    deprecated alias core.stdc.complex.cproj      cproj;
+    deprecated alias core.stdc.complex.cprojf     cproj;
+    deprecated alias core.stdc.complex.cprojl     cproj;
+//  deprecated alias core.stdc.complex.creal      creal;
+//  deprecated alias core.stdc.complex.crealf     creal;
+//  deprecated alias core.stdc.complex.creall     creal;
 }
diff --git a/libphobos/libdruntime/core/stdc/wchar_.d b/libphobos/libdruntime/core/stdc/wchar_.d
index eecc8ef..6da5618 100644
--- a/libphobos/libdruntime/core/stdc/wchar_.d
+++ b/libphobos/libdruntime/core/stdc/wchar_.d
@@ -173,12 +173,13 @@ extern (D) @trusted
     wint_t getwchar()                     { return fgetwc(stdin);     }
     ///
     wint_t putwchar(wchar_t c)            { return fputwc(c,stdout);  }
-    ///
-    wint_t getwc(FILE* stream)            { return fgetwc(stream);    }
-    ///
-    wint_t putwc(wchar_t c, FILE* stream) { return fputwc(c, stream); }
 }
 
+///
+alias getwc = fgetwc;
+///
+alias putwc = fputwc;
+
 // No unsafe pointer manipulation.
 @trusted
 {
diff --git a/libphobos/libdruntime/core/sys/darwin/config.d b/libphobos/libdruntime/core/sys/darwin/config.d
new file mode 100644
index 0000000..87f3fd4
--- /dev/null
+++ b/libphobos/libdruntime/core/sys/darwin/config.d
@@ -0,0 +1,53 @@
+/**
+ * D header file for Darwin.
+ *
+ * Copyright: Copyright (c) 2021 D Language Foundation
+ * Authors: Iain Buclaw
+ */
+module core.sys.darwin.config;
+
+version (OSX)
+    version = Darwin;
+else version (iOS)
+    version = Darwin;
+else version (TVOS)
+    version = Darwin;
+else version (WatchOS)
+    version = Darwin;
+
+version (Darwin):
+
+public import core.sys.posix.config;
+
+enum __MAC_10_0    = 100000;
+enum __MAC_10_1    = 100100;
+enum __MAC_10_2    = 100200;
+enum __MAC_10_3    = 100300;
+enum __MAC_10_4    = 100400;
+enum __MAC_10_5    = 100500;
+enum __MAC_10_6    = 100600;
+enum __MAC_10_7    = 100700;
+enum __MAC_10_8    = 100800;
+enum __MAC_10_9    = 100900;
+enum __MAC_10_10   = 101000;
+enum __MAC_10_10_2 = 101002;
+enum __MAC_10_10_3 = 101003;
+enum __MAC_10_11   = 101100;
+enum __MAC_10_11_2 = 101102;
+enum __MAC_10_11_3 = 101103;
+enum __MAC_10_11_4 = 101104;
+enum __MAC_10_12   = 101200;
+enum __MAC_10_12_1 = 101201;
+enum __MAC_10_12_2 = 101202;
+enum __MAC_10_12_4 = 101204;
+enum __MAC_10_13   = 101300;
+enum __MAC_10_13_1 = 101301;
+enum __MAC_10_13_2 = 101302;
+enum __MAC_10_13_4 = 101304;
+enum __MAC_10_14   = 101400;
+enum __MAC_10_14_1 = 101401;
+enum __MAC_10_14_4 = 101404;
+enum __MAC_10_15   = 101500;
+enum __MAC_10_15_1 = 101501;
+enum __MAC_10_16   = 101501;
+enum __MAC_11_0    = 110000;
diff --git a/libphobos/libdruntime/core/sys/darwin/fcntl.d b/libphobos/libdruntime/core/sys/darwin/fcntl.d
new file mode 100644
index 0000000..47d895a
--- /dev/null
+++ b/libphobos/libdruntime/core/sys/darwin/fcntl.d
@@ -0,0 +1,20 @@
+module core.sys.darwin.fcntl;
+
+public import core.sys.posix.fcntl;
+
+version (OSX)
+    version = Darwin;
+else version (iOS)
+    version = Darwin;
+else version (TVOS)
+    version = Darwin;
+else version (WatchOS)
+    version = Darwin;
+
+version (Darwin):
+extern (C):
+nothrow:
+@nogc:
+@system:
+
+enum F_FULLFSYNC = 51;
diff --git a/libphobos/libdruntime/core/sys/darwin/mach/thread_act.d b/libphobos/libdruntime/core/sys/darwin/mach/thread_act.d
index b61673f..d455d1b 100644
--- a/libphobos/libdruntime/core/sys/darwin/mach/thread_act.d
+++ b/libphobos/libdruntime/core/sys/darwin/mach/thread_act.d
@@ -38,6 +38,10 @@ version (AArch64)
     version = AnyARM;
 version (ARM)
     version = AnyARM;
+version (PPC)
+    version = AnyPPC;
+version (PPC64)
+    version = AnyPPC;
 
 version (i386)
 {
@@ -235,3 +239,65 @@ else version (AnyARM)
     kern_return_t thread_resume(thread_act_t);
     kern_return_t thread_get_state(thread_act_t, thread_state_flavor_t, thread_state_t*, mach_msg_type_number_t*);
 }
+else version (AnyPPC)
+{
+    alias thread_act_t = mach_port_t;
+    alias thread_state_t = void;
+    alias thread_state_flavor_t = int;
+    alias mach_msg_type_number_t = natural_t;
+
+    enum
+    {
+        PPC_THREAD_STATE = 1,
+        PPC_FLOAT_STATE = 2,
+        PPC_EXCEPTION_STATE = 3,
+        PPC_VECTOR_STATE = 4,
+        PPC_THREAD_STATE64 = 5,
+        PPC_EXCEPTION_STATE64 = 6,
+        THREAD_STATE_NONE = 7
+    }
+
+    struct ppc_thread_state_t
+    {
+        uint srr0;   /// Instruction address register (PC)
+        uint srr1;   /// Machine state register (supervisor)
+        uint[32] r;  /// General purpose register r0-r31
+        uint cr;     /// Condition register
+        uint xer;    /// User's integer exception register
+        uint lr;     /// Link register
+        uint ctr;    /// Count register
+        uint mq;     /// MQ register (601 only)
+        uint vrsave; /// Vector save register
+    }
+
+    alias ppc_thread_state32_t = ppc_thread_state_t;
+
+    struct ppc_thread_state64_t
+    {
+        ulong srr0;   /// Instruction address register (PC)
+        ulong srr1;   /// Machine state register (supervisor)
+        ulong[32] r;  /// General purpose register r0-r31
+        uint cr;      /// Condition register
+        uint pad0;
+        ulong xer;    /// User's integer exception register
+        ulong lr;     /// Link register
+        ulong ctr;    /// Count register
+        uint vrsave;  /// Vector save register
+        uint pad1;
+    }
+
+    enum : mach_msg_type_number_t
+    {
+        PPC_THREAD_STATE_COUNT = cast(mach_msg_type_number_t) (ppc_thread_state_t.sizeof / uint.sizeof),
+        PPC_THREAD_STATE32_COUNT = cast(mach_msg_type_number_t) (ppc_thread_state32_t.sizeof / uint.sizeof),
+        PPC_THREAD_STATE64_COUNT = cast(mach_msg_type_number_t) (ppc_thread_state64_t.sizeof / uint.sizeof),
+    }
+
+    alias MACHINE_THREAD_STATE = PPC_THREAD_STATE;
+    alias MACHINE_THREAD_STATE_COUNT = PPC_THREAD_STATE_COUNT;
+
+    mach_port_t   mach_thread_self();
+    kern_return_t thread_suspend(thread_act_t);
+    kern_return_t thread_resume(thread_act_t);
+    kern_return_t thread_get_state(thread_act_t, thread_state_flavor_t, thread_state_t*, mach_msg_type_number_t*);
+}
diff --git a/libphobos/libdruntime/core/sys/dragonflybsd/dlfcn.d b/libphobos/libdruntime/core/sys/dragonflybsd/dlfcn.d
index 1d3812f..2c5d8d7 100644
--- a/libphobos/libdruntime/core/sys/dragonflybsd/dlfcn.d
+++ b/libphobos/libdruntime/core/sys/dragonflybsd/dlfcn.d
@@ -82,16 +82,13 @@ struct __dlfunc_arg {
 
 alias dlfunc_t = void function(__dlfunc_arg);
 
-private template __externC(RT, P...)
-{
-    alias __externC = extern(C) RT function(P) nothrow @nogc @system;
-}
-
 /* XSI functions first. */
-static assert(is(typeof(&dlclose) == __externC!(int, void*)));
-static assert(is(typeof(&dlerror) == __externC!(char*)));
-static assert(is(typeof(&dlopen)  == __externC!(void*, const char*, int)));
-static assert(is(typeof(&dlsym)   == __externC!(void*, void*, const char*)));
+extern(C) {
+    static assert(is(typeof(&dlclose) == int function(void*)));
+    static assert(is(typeof(&dlerror) == char* function()));
+    static assert(is(typeof(&dlopen)  == void* function(const scope char*, int)));
+    static assert(is(typeof(&dlsym)   == void* function(void*, const scope char*)));
+}
 
 void*    fdlopen(int, int);
 int      dladdr(const(void)*, Dl_info*);
diff --git a/libphobos/libdruntime/core/sys/freebsd/dlfcn.d b/libphobos/libdruntime/core/sys/freebsd/dlfcn.d
index fad9141..7baacfe 100644
--- a/libphobos/libdruntime/core/sys/freebsd/dlfcn.d
+++ b/libphobos/libdruntime/core/sys/freebsd/dlfcn.d
@@ -90,8 +90,8 @@ static if (__BSD_VISIBLE)
 extern(C) {
     static assert(is(typeof(&dlclose) == int function(void*)));
     static assert(is(typeof(&dlerror) == char* function()));
-    static assert(is(typeof(&dlopen)  == void* function(in char*, int)));
-    static assert(is(typeof(&dlsym)   == void* function(void*, in char*)));
+    static assert(is(typeof(&dlopen)  == void* function(const scope char*, int)));
+    static assert(is(typeof(&dlsym)   == void* function(void*, const scope char*)));
 }
 
 static if (__BSD_VISIBLE)
diff --git a/libphobos/libdruntime/core/sys/linux/epoll.d b/libphobos/libdruntime/core/sys/linux/epoll.d
index 0c3aed9..f5ff7db 100644
--- a/libphobos/libdruntime/core/sys/linux/epoll.d
+++ b/libphobos/libdruntime/core/sys/linux/epoll.d
@@ -10,6 +10,8 @@ module core.sys.linux.epoll;
 
 version (linux):
 
+import core.sys.posix.signal : sigset_t;
+
 extern (C):
 @system:
 @nogc:
@@ -52,16 +54,19 @@ enum
     EPOLLHUP    = 0x010,
     EPOLLRDHUP  = 0x2000, // since Linux 2.6.17
     EPOLLEXCLUSIVE = 1u << 28, // since Linux 4.5
+    EPOLLWAKEUP = 1u << 29,
     EPOLLONESHOT = 1u << 30,
     EPOLLET     = 1u << 31
 }
 
-/* Valid opcodes ( "op" parameter ) to issue to epoll_ctl().  */
+/**
+ * Valid opcodes ( "op" parameter ) to issue to epoll_ctl().
+ */
 enum
 {
-    EPOLL_CTL_ADD = 1, // Add a file descriptor to the interface.
-    EPOLL_CTL_DEL = 2, // Remove a file descriptor from the interface.
-    EPOLL_CTL_MOD = 3, // Change file descriptor epoll_event structure.
+    EPOLL_CTL_ADD = 1, /// Add a file descriptor to the interface.
+    EPOLL_CTL_DEL = 2, /// Remove a file descriptor from the interface.
+    EPOLL_CTL_MOD = 3, /// Change file descriptor epoll_event structure.
 }
 
 version (X86_Any)
@@ -142,7 +147,82 @@ union epoll_data_t
     ulong u64;
 }
 
+/**
+ * Creates an epoll instance.
+ *
+ * Params:
+ *   size = a hint specifying the number of file descriptors to be associated
+ *          with the new instance.  T
+ * Returns: an fd for the new instance. The fd returned by epoll_create() should
+ *          be closed with close().
+ * See_also: epoll_create1 (int flags)
+ */
 int epoll_create (int size);
+
+/* Same as epoll_create but with an FLAGS parameter.  The unused SIZE
+   parameter has been dropped.  */
+
+/**
+ * Creates an epoll instance.
+ *
+ * Params:
+ *   flags = a specified flag. If flags is 0, then, other than the fact that the
+ *           obsolete size argument is dropped, epoll_create1() is the same as
+ *           epoll_create().
+ * Returns: an fd for the new instance. The fd returned by epoll_create() should
+ *          be closed with close().
+ * See_also: epoll_create (int size)
+ */
 int epoll_create1 (int flags);
+
+/**
+ * Manipulate an epoll instance
+ *
+ * Params:
+ *   epfd = an epoll file descriptor instance
+ *   op = one of the EPOLL_CTL_* constants
+ *   fd = target file descriptor of the operation
+ *   event = describes which events the caller is interested in and any
+ *           associated user dat
+ * Returns: 0 in case of success, -1 in case of error ( the "errno" variable
+ *          will contain the specific error code )
+ */
 int epoll_ctl (int epfd, int op, int fd, epoll_event *event);
+
+
+/**
+ * Wait for events on an epoll instance.
+ *
+ *
+ * Params:
+ *   epfd = an epoll file descriptor instance
+ *   events = a buffer that will contain triggered events
+ *   maxevents = the maximum number of events to be returned ( usually size of
+ *               "events" )
+ *   timeout = specifies the maximum wait time in milliseconds (-1 == infinite)
+ *
+ * Returns: the number of triggered events returned in "events" buffer. Or -1 in
+ *          case of error with the "errno" variable set to the specific error
+ *          code.
+ */
 int epoll_wait (int epfd, epoll_event *events, int maxevents, int timeout);
+
+/**
+ * Wait for events on an epoll instance
+ *
+ *
+ * Params:
+ *   epfd = an epoll file descriptor instance
+ *   events = a buffer that will contain triggered events
+ *   maxevents = the maximum number of events to be returned ( usually size of
+ *               "events" )
+ *   timeout = specifies the maximum wait time in milliseconds (-1 == infinite)
+ *   ss = a signal set. May be specified as `null`, in which case epoll_pwait() is
+ *        equivalent to epoll_wait().
+ *
+ * Returns: the number of triggered events returned in "events" buffer. Or -1 in
+ *          case of error with the "errno" variable set to the specific error
+ *          code.
+ */
+int epoll_pwait (int epfd, epoll_event *events, int maxevents, int timeout,
+    const sigset_t *ss);
diff --git a/libphobos/libdruntime/core/sys/netbsd/dlfcn.d b/libphobos/libdruntime/core/sys/netbsd/dlfcn.d
index dbbcc76..468ffbf 100644
--- a/libphobos/libdruntime/core/sys/netbsd/dlfcn.d
+++ b/libphobos/libdruntime/core/sys/netbsd/dlfcn.d
@@ -87,16 +87,13 @@ static if (__BSD_VISIBLE)
     }
 }
 
-private template __externC(RT, P...)
-{
-    alias __externC = extern(C) RT function(P) nothrow @nogc;
-}
-
 /* XSI functions first. */
-static assert(is(typeof(&dlclose) == __externC!(int, void*)));
-static assert(is(typeof(&dlerror) == __externC!(char*)));
-static assert(is(typeof(&dlopen)  == __externC!(void*, const char*, int)));
-static assert(is(typeof(&dlsym)   == __externC!(void*, void*, const char*)));
+extern(C) {
+    static assert(is(typeof(&dlclose) == int function(void*)));
+    static assert(is(typeof(&dlerror) == char* function()));
+    static assert(is(typeof(&dlopen)  == void* function(const scope char*, int)));
+    static assert(is(typeof(&dlsym)   == void* function(void*, const scope char*)));
+}
 
 static if (__BSD_VISIBLE)
 {
diff --git a/libphobos/libdruntime/core/sys/openbsd/string.d b/libphobos/libdruntime/core/sys/openbsd/string.d
index 8d35b9c..cb978c8 100644
--- a/libphobos/libdruntime/core/sys/openbsd/string.d
+++ b/libphobos/libdruntime/core/sys/openbsd/string.d
@@ -18,4 +18,6 @@ nothrow:
 static if (__BSD_VISIBLE)
 {
     pure void* memmem(return const void* haystack, size_t haystacklen, scope const void* needle, size_t needlelen);
+    pure int timingsafe_bcmp(scope const void*, scope const void*, size_t);
+    pure int timingsafe_memcmp(scope const void*, scope const void*, size_t);
 }
diff --git a/libphobos/libdruntime/core/sys/openbsd/sys/link_elf.d b/libphobos/libdruntime/core/sys/openbsd/sys/link_elf.d
index f88671a..55fc792 100644
--- a/libphobos/libdruntime/core/sys/openbsd/sys/link_elf.d
+++ b/libphobos/libdruntime/core/sys/openbsd/sys/link_elf.d
@@ -63,3 +63,8 @@ private alias int function(dl_phdr_info*, size_t, void *) @nogc dl_iterate_phdr_
 
 int dl_iterate_phdr(dl_iterate_phdr_cb __callback, void*__data);
 int dl_iterate_phdr(dl_iterate_phdr_cb_ngc __callback, void*__data) @nogc;
+
+int _rtld_addr_phdr(const void*, dl_phdr_info*) @nogc
+{
+    return 0;
+}
diff --git a/libphobos/libdruntime/core/sys/openbsd/unistd.d b/libphobos/libdruntime/core/sys/openbsd/unistd.d
new file mode 100644
index 0000000..ddd102c
--- /dev/null
+++ b/libphobos/libdruntime/core/sys/openbsd/unistd.d
@@ -0,0 +1,17 @@
+/**
+  * D header file for OpenBSD unistd.h.
+  *
+  * Copyright: Copyright © 2021, The D Language Foundation
+  * License: <a href="http://www.boost.org/LICENSE_1_0.txt">Boost License 1.0</a>.
+  * Authors: Brian Callahan
+  */
+module core.sys.openbsd.unistd;
+public import core.sys.posix.unistd;
+
+version (OpenBSD):
+extern (C):
+nothrow:
+@nogc:
+
+int pledge(const scope char*, const scope char*);
+int unveil(const scope char*, const scope char*);
diff --git a/libphobos/libdruntime/core/sys/posix/config.d b/libphobos/libdruntime/core/sys/posix/config.d
index c02debff..3b575fa 100644
--- a/libphobos/libdruntime/core/sys/posix/config.d
+++ b/libphobos/libdruntime/core/sys/posix/config.d
@@ -117,6 +117,7 @@ else version (CRuntime_UClibc)
 else version (CRuntime_Bionic)
 {
     enum _GNU_SOURCE         = false;
+    enum __USE_FILE_OFFSET64 = false; // see https://android.googlesource.com/platform/bionic/+/master/docs/32-bit-abi.md
     enum __USE_GNU           = _GNU_SOURCE;
 
     version (D_LP64)
diff --git a/libphobos/libdruntime/core/sys/posix/dlfcn.d b/libphobos/libdruntime/core/sys/posix/dlfcn.d
index e97c7ea..f6476ec 100644
--- a/libphobos/libdruntime/core/sys/posix/dlfcn.d
+++ b/libphobos/libdruntime/core/sys/posix/dlfcn.d
@@ -139,7 +139,7 @@ else version (Darwin)
     char* dlerror();
     void* dlopen(const scope char*, int);
     void* dlsym(void*, const scope char*);
-    int   dladdr(void* addr, Dl_info* info);
+    int   dladdr(scope const void* addr, Dl_info* info);
 
     struct Dl_info
     {
@@ -158,8 +158,8 @@ else version (FreeBSD)
 
     int   dlclose(void*);
     char* dlerror();
-    void* dlopen(in char*, int);
-    void* dlsym(void*, in char*);
+    void* dlopen(const scope char*, int);
+    void* dlsym(void*, const scope char*);
     int   dladdr(const(void)* addr, Dl_info* info);
 
     struct Dl_info
@@ -294,6 +294,15 @@ else version (CRuntime_Musl)
     const(char)* dlerror();
     void*        dlopen(const scope char*, int);
     void*        dlsym(void*, const scope char*);
+
+    int dladdr(scope const void *addr, Dl_info *info);
+    struct Dl_info
+    {
+        const(char)* dli_fname;
+        void*        dli_fbase;
+        const(char)* dli_sname;
+        void*        dli_saddr;
+    }
 }
 else version (CRuntime_UClibc)
 {
diff --git a/libphobos/libdruntime/core/sys/posix/signal.d b/libphobos/libdruntime/core/sys/posix/signal.d
index 44f45f2..0dce8c5 100644
--- a/libphobos/libdruntime/core/sys/posix/signal.d
+++ b/libphobos/libdruntime/core/sys/posix/signal.d
@@ -3503,7 +3503,7 @@ struct sigevent
     pthread_attr_t* sigev_notify_attributes;
 }
 
-int sigqueue(pid_t, int, in sigval);
+int sigqueue(pid_t, int, const sigval);
 int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
 int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 */
@@ -3543,7 +3543,7 @@ version (CRuntime_Glibc)
         } _sigev_un_t _sigev_un;
     }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
@@ -3566,7 +3566,7 @@ else version (FreeBSD)
         }
     }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
@@ -3581,7 +3581,7 @@ else version (NetBSD)
         void /* pthread_attr_t */*sigev_notify_attributes;
     }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
@@ -3613,7 +3613,7 @@ else version (DragonFlyBSD)
         void function(_sigval_t)  sigev_notify_function;
     }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
@@ -3640,7 +3640,7 @@ else version (Solaris)
         int __sigev_pad2;
     }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
@@ -3717,7 +3717,7 @@ else version (CRuntime_UClibc)
     @property void function(sigval) sigev_notify_function(ref sigevent _sigevent) { return _sigevent._sigev_un._sigev_thread._function; }
     @property void* sigev_notify_attributes(ref sigevent _sigevent) { return  _sigevent._sigev_un._sigev_thread._attribute; }
 
-    int sigqueue(pid_t, int, in sigval);
+    int sigqueue(pid_t, int, const sigval);
     int sigtimedwait(const scope sigset_t*, siginfo_t*, const scope timespec*);
     int sigwaitinfo(const scope sigset_t*, siginfo_t*);
 }
diff --git a/libphobos/libdruntime/core/sys/posix/stdio.d b/libphobos/libdruntime/core/sys/posix/stdio.d
index 031bcb7..41b52da 100644
--- a/libphobos/libdruntime/core/sys/posix/stdio.d
+++ b/libphobos/libdruntime/core/sys/posix/stdio.d
@@ -516,6 +516,46 @@ version (CRuntime_Glibc)
     int    putc_unlocked(int, FILE*);
     int    putchar_unlocked(int);
 }
+else version (CRuntime_Musl)
+{
+    void   flockfile(FILE*);
+    int    ftrylockfile(FILE*);
+    void   funlockfile(FILE*);
+    int    getc_unlocked(FILE*);
+    int    getchar_unlocked();
+    int    putc_unlocked(int, FILE*);
+    int    putchar_unlocked(int);
+}
+else version (Darwin)
+{
+    void   flockfile(FILE*);
+    int    ftrylockfile(FILE*);
+    void   funlockfile(FILE*);
+    int    getc_unlocked(FILE*);
+    int    getchar_unlocked();
+    int    putc_unlocked(int, FILE*);
+    int    putchar_unlocked(int);
+}
+else version (FreeBSD)
+{
+    void   flockfile(FILE*);
+    int    ftrylockfile(FILE*);
+    void   funlockfile(FILE*);
+    int    getc_unlocked(FILE*);
+    int    getchar_unlocked();
+    int    putc_unlocked(int, FILE*);
+    int    putchar_unlocked(int);
+}
+else version (NetBSD)
+{
+    void   flockfile(FILE*);
+    int    ftrylockfile(FILE*);
+    void   funlockfile(FILE*);
+    int    getc_unlocked(FILE*);
+    int    getchar_unlocked();
+    int    putc_unlocked(int, FILE*);
+    int    putchar_unlocked(int);
+}
 else version (OpenBSD)
 {
     void   flockfile(FILE*);
@@ -526,6 +566,16 @@ else version (OpenBSD)
     int    putc_unlocked(int, FILE*);
     int    putchar_unlocked(int);
 }
+else version (DragonFlyBSD)
+{
+    void   flockfile(FILE*);
+    int    ftrylockfile(FILE*);
+    void   funlockfile(FILE*);
+    int    getc_unlocked(FILE*);
+    int    getchar_unlocked();
+    int    putc_unlocked(int, FILE*);
+    int    putchar_unlocked(int);
+}
 else version (Solaris)
 {
     void   flockfile(FILE*);
diff --git a/libphobos/libdruntime/core/sys/posix/unistd.d b/libphobos/libdruntime/core/sys/posix/unistd.d
index a691884..d996556 100644
--- a/libphobos/libdruntime/core/sys/posix/unistd.d
+++ b/libphobos/libdruntime/core/sys/posix/unistd.d
@@ -2722,3 +2722,51 @@ else version (CRuntime_UClibc)
     int        truncate(const scope char*, off_t);
   }
 }
+
+// Non-standard definition to access user process environment
+version (CRuntime_Glibc)
+{
+    extern __gshared const char** environ;
+}
+else version (Darwin)
+{
+    extern (D) @property const(char**) environ()()
+    {
+        pragma (inline, true);
+        import core.sys.darwin.crt_externs : _NSGetEnviron;
+        return *_NSGetEnviron();
+    }
+}
+else version (FreeBSD)
+{
+    extern __gshared const char** environ;
+}
+else version (NetBSD)
+{
+    extern __gshared const char** environ;
+}
+else version (OpenBSD)
+{
+    extern __gshared const char** environ;
+}
+else version (DragonFlyBSD)
+{
+    extern __gshared const char** environ;
+}
+else version (CRuntime_Bionic)
+{
+    extern __gshared const char** environ;
+}
+else version (CRuntime_Musl)
+{
+    extern __gshared const char** environ;
+}
+else version (Solaris)
+{
+    extern __gshared const char** environ;
+}
+else version (CRuntime_UClibc)
+{
+    extern __gshared const char** __environ;
+    alias environ = __environ;
+}
diff --git a/libphobos/libdruntime/core/sys/windows/com.d b/libphobos/libdruntime/core/sys/windows/com.d
index 90a2943..6935dd9 100644
--- a/libphobos/libdruntime/core/sys/windows/com.d
+++ b/libphobos/libdruntime/core/sys/windows/com.d
@@ -39,16 +39,16 @@ public import core.sys.windows.winerror :
     RPC_E_CHANGED_MODE;
 
 public import core.sys.windows.wtypes :
-    OLECHAR, LPOLESTR, LPCOLESTR;
+    CLSCTX, OLECHAR, LPOLESTR, LPCOLESTR;
 
-alias CLSCTX_INPROC_SERVER     = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_SERVER    ;
-alias CLSCTX_INPROC_HANDLER    = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_HANDLER   ;
-alias CLSCTX_LOCAL_SERVER      = core.sys.windows.wtypes.CLSCTX.CLSCTX_LOCAL_SERVER     ;
-alias CLSCTX_INPROC_SERVER16   = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_SERVER16  ;
-alias CLSCTX_REMOTE_SERVER     = core.sys.windows.wtypes.CLSCTX.CLSCTX_REMOTE_SERVER    ;
-alias CLSCTX_INPROC_HANDLER16  = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_HANDLER16 ;
-alias CLSCTX_INPROC_SERVERX86  = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_SERVERX86 ;
-alias CLSCTX_INPROC_HANDLERX86 = core.sys.windows.wtypes.CLSCTX.CLSCTX_INPROC_HANDLERX86;
+alias CLSCTX_INPROC_SERVER     = CLSCTX.CLSCTX_INPROC_SERVER    ;
+alias CLSCTX_INPROC_HANDLER    = CLSCTX.CLSCTX_INPROC_HANDLER   ;
+alias CLSCTX_LOCAL_SERVER      = CLSCTX.CLSCTX_LOCAL_SERVER     ;
+alias CLSCTX_INPROC_SERVER16   = CLSCTX.CLSCTX_INPROC_SERVER16  ;
+alias CLSCTX_REMOTE_SERVER     = CLSCTX.CLSCTX_REMOTE_SERVER    ;
+alias CLSCTX_INPROC_HANDLER16  = CLSCTX.CLSCTX_INPROC_HANDLER16 ;
+alias CLSCTX_INPROC_SERVERX86  = CLSCTX.CLSCTX_INPROC_SERVERX86 ;
+alias CLSCTX_INPROC_HANDLERX86 = CLSCTX.CLSCTX_INPROC_HANDLERX86;
 
 alias COINIT_APARTMENTTHREADED   = COINIT.COINIT_APARTMENTTHREADED;
 alias COINIT_MULTITHREADED       = COINIT.COINIT_MULTITHREADED    ;
@@ -57,12 +57,12 @@ alias COINIT_SPEED_OVER_MEMORY   = COINIT.COINIT_SPEED_OVER_MEMORY;
 
 public import core.sys.windows.uuid;
 
-extern (System)
+extern (Windows)
 {
 
 class ComObject : IUnknown
 {
-extern (System):
+extern (Windows):
     HRESULT QueryInterface(const(IID)* riid, void** ppv)
     {
         if (*riid == IID_IUnknown)
diff --git a/libphobos/libdruntime/core/sys/windows/dbghelp.d b/libphobos/libdruntime/core/sys/windows/dbghelp.d
index 8c98270..9848fb9 100644
--- a/libphobos/libdruntime/core/sys/windows/dbghelp.d
+++ b/libphobos/libdruntime/core/sys/windows/dbghelp.d
@@ -18,7 +18,7 @@ import core.sys.windows.windef;
 
 public import core.sys.windows.dbghelp_types;
 
-extern(System)
+extern(Windows)
 {
     alias BOOL         function(HANDLE hProcess, DWORD64 lpBaseAddress, PVOID lpBuffer, DWORD nSize, LPDWORD lpNumberOfBytesRead) ReadProcessMemoryProc64;
     alias PVOID        function(HANDLE hProcess, DWORD64 AddrBase) FunctionTableAccessProc64;
diff --git a/libphobos/libdruntime/core/sys/windows/dll.d b/libphobos/libdruntime/core/sys/windows/dll.d
index 9f36ac3..cc2422b 100644
--- a/libphobos/libdruntime/core/sys/windows/dll.d
+++ b/libphobos/libdruntime/core/sys/windows/dll.d
@@ -31,17 +31,7 @@ public import core.sys.windows.threadaux;
 //  not access tls_array[tls_index] as needed for thread local _tlsstart and _tlsend
 extern (C)
 {
-        version (MinGW)
-        {
-            extern __gshared void* _tls_start;
-            extern __gshared void* _tls_end;
-            extern __gshared void* __xl_a;
-
-            alias _tls_start _tlsstart;
-            alias _tls_end   _tlsend;
-            alias __xl_a     _tls_callbacks_a;
-        }
-        else version (Win32)
+    version (Win32)
     {
         version (CRuntime_DigitalMars)
         {
@@ -424,7 +414,7 @@ int dll_getRefCount( HINSTANCE hInstance ) nothrow @nogc
     {
         version (GNU_InlineAsm)
         {
-            asm pure nothrow @nogc { "movq %%gs:0x60, %0;" : "=r" peb; }
+            asm pure nothrow @nogc { "movq %%gs:0x60, %0;" : "=r" (peb); }
         }
         else
         {
@@ -441,7 +431,7 @@ int dll_getRefCount( HINSTANCE hInstance ) nothrow @nogc
     {
         version (GNU_InlineAsm)
         {
-            asm pure nothrow @nogc { "movl %%fs:0x30, %0;" : "=r" peb; }
+            asm pure nothrow @nogc { "movl %%fs:0x30, %0;" : "=r" (peb); }
         }
         else
         {
diff --git a/libphobos/libdruntime/core/sys/windows/stdc/malloc.d b/libphobos/libdruntime/core/sys/windows/stdc/malloc.d
new file mode 100644
index 0000000..f52ba37
--- /dev/null
+++ b/libphobos/libdruntime/core/sys/windows/stdc/malloc.d
@@ -0,0 +1,26 @@
+/**
+  * D header file for Windows malloc.h.
+ *
+ * Translated from MinGW Windows headers
+ *
+ * Authors: Iain Buclaw
+ * License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
+ * Source: $(DRUNTIMESRC src/core/sys/windows/stdc/_malloc.d)
+ */
+module core.sys.windows.stdc.malloc;
+version (CRuntime_Microsoft):
+extern (C):
+@system:
+nothrow:
+@nogc:
+
+export void* _recalloc(void*, size_t, size_t);
+
+export void _aligned_free(void*);
+export void* _aligned_malloc(size_t, size_t);
+
+export void* _aligned_offset_malloc(size_t, size_t, size_t);
+export void* _aligned_realloc(void*, size_t, size_t);
+export void* _aligned_recalloc(void*, size_t, size_t, size_t);
+export void* _aligned_offset_realloc(void*, size_t, size_t, size_t);
+export void* _aligned_offset_recalloc(void*, size_t, size_t, size_t, size_t);
diff --git a/libphobos/libdruntime/core/sys/windows/threadaux.d b/libphobos/libdruntime/core/sys/windows/threadaux.d
index fb4d1ee..34fda65 100644
--- a/libphobos/libdruntime/core/sys/windows/threadaux.d
+++ b/libphobos/libdruntime/core/sys/windows/threadaux.d
@@ -172,7 +172,7 @@ struct thread_aux
             version (GNU_InlineAsm)
             {
                 void** teb;
-                asm pure nothrow @nogc { "movl %%fs:0x18, %0;" : "=r" teb; }
+                asm pure nothrow @nogc { "movl %%fs:0x18, %0;" : "=r" (teb); }
                 return teb;
             }
             else
@@ -190,7 +190,7 @@ struct thread_aux
             version (GNU_InlineAsm)
             {
                 void** teb;
-                asm pure nothrow @nogc { "movq %%gs:0x30, %0;" : "=r" teb; }
+                asm pure nothrow @nogc { "movq %%gs:0x30, %0;" : "=r" (teb); }
                 return teb;
             }
             else
diff --git a/libphobos/libdruntime/core/thread/fiber.d b/libphobos/libdruntime/core/thread/fiber.d
index 3270f2e..f4c04ce 100644
--- a/libphobos/libdruntime/core/thread/fiber.d
+++ b/libphobos/libdruntime/core/thread/fiber.d
@@ -82,6 +82,8 @@ private
 
             version (MinGW)
                 version = GNU_AsmX86_Windows;
+            else version (OSX)
+                version = AsmX86_Posix;
             else version (Posix)
                 version = AsmX86_Posix;
         }
@@ -105,13 +107,21 @@ private
 
             version (MinGW)
                 version = GNU_AsmX86_64_Windows;
+            else version (OSX)
+                version = AsmX86_64_Posix;
             else version (Posix)
                 version = AsmX86_64_Posix;
         }
     }
     else version (PPC)
     {
-        version (Posix)
+        version (OSX)
+        {
+            version = AsmPPC_Darwin;
+            version = AsmExternal;
+            version = AlignFiberStackTo16Byte;
+        }
+        else version (Posix)
         {
             version = AsmPPC_Posix;
             version = AsmExternal;
@@ -119,7 +129,13 @@ private
     }
     else version (PPC64)
     {
-        version (Posix)
+        version (OSX)
+        {
+            version = AsmPPC_Darwin;
+            version = AsmExternal;
+            version = AlignFiberStackTo16Byte;
+        }
+        else version (Posix)
         {
             version = AlignFiberStackTo16Byte;
         }
@@ -883,6 +899,7 @@ class Fiber
      */
     static Fiber getThis() @safe nothrow @nogc
     {
+        version (GNU) pragma(inline, false);
         return sm_this;
     }
 
@@ -1346,6 +1363,28 @@ private:
 
             assert( (cast(size_t) pstack & 0x0f) == 0 );
         }
+        else version (AsmPPC_Darwin)
+        {
+            version (StackGrowsDown) {}
+            else static assert(false, "PowerPC Darwin only supports decrementing stacks");
+
+            uint wsize = size_t.sizeof;
+
+            // linkage + regs + FPRs + VRs
+            uint space = 8 * wsize + 20 * wsize + 18 * 8 + 12 * 16;
+            (cast(ubyte*)pstack - space)[0 .. space] = 0;
+
+            pstack -= wsize * 6;
+            *cast(size_t*)pstack = cast(size_t) &fiber_entryPoint; // LR
+            pstack -= wsize * 22;
+
+            // On Darwin PPC64 pthread self is in R13 (which is reserved).
+            // At present, it is not safe to migrate fibers between threads, but if that
+            // changes, then updating the value of R13 will also need to be handled.
+            version (PPC64)
+              *cast(size_t*)(pstack + wsize) = cast(size_t) Thread.getThis().m_addr;
+            assert( (cast(size_t) pstack & 0x0f) == 0 );
+        }
         else version (AsmMIPS_O32_Posix)
         {
             version (StackGrowsDown) {}
@@ -1731,6 +1770,11 @@ unittest
 // Multiple threads running shared fibers
 version (PPC)   version = UnsafeFiberMigration;
 version (PPC64) version = UnsafeFiberMigration;
+version (OSX)
+{
+    version (X86)    version = UnsafeFiberMigration;
+    version (X86_64) version = UnsafeFiberMigration;
+}
 
 version (UnsafeFiberMigration)
 {
diff --git a/libphobos/libdruntime/core/thread/osthread.d b/libphobos/libdruntime/core/thread/osthread.d
index defdc95..9fcd30e 100644
--- a/libphobos/libdruntime/core/thread/osthread.d
+++ b/libphobos/libdruntime/core/thread/osthread.d
@@ -349,7 +349,8 @@ class Thread : ThreadBase
         }
         else version (Posix)
         {
-            pthread_detach( m_addr );
+            if (m_addr != m_addr.init)
+                pthread_detach( m_addr );
             m_addr = m_addr.init;
         }
         version (Darwin)
@@ -420,6 +421,17 @@ class Thread : ThreadBase
         {
             uint[16]        m_reg; // r0-r15
         }
+        else version (PPC)
+        {
+            // Make the assumption that we only care about non-fp and non-vr regs.
+            // ??? : it seems plausible that a valid address can be copied into a VR.
+            uint[32]        m_reg; // r0-31
+        }
+        else version (PPC64)
+        {
+            // As above.
+            ulong[32]       m_reg; // r0-31
+        }
         else
         {
             static assert(false, "Architecture not supported." );
@@ -510,7 +522,7 @@ class Thread : ThreadBase
                 {
                     version (GNU)
                     {
-                        auto libs = externDFunc!("gcc.sections.elf_shared.pinLoadedLibraries",
+                        auto libs = externDFunc!("gcc.sections.pinLoadedLibraries",
                                                  void* function() @nogc nothrow)();
                     }
                     else
@@ -527,7 +539,7 @@ class Thread : ThreadBase
                     {
                         version (GNU)
                         {
-                            externDFunc!("gcc.sections.elf_shared.unpinLoadedLibraries",
+                            externDFunc!("gcc.sections.unpinLoadedLibraries",
                                          void function(void*) @nogc nothrow)(libs);
                         }
                         else
@@ -578,7 +590,7 @@ class Thread : ThreadBase
     {
         version (Windows)
         {
-            if ( WaitForSingleObject( m_hndl, INFINITE ) != WAIT_OBJECT_0 )
+            if ( m_addr != m_addr.init && WaitForSingleObject( m_hndl, INFINITE ) != WAIT_OBJECT_0 )
                 throw new ThreadException( "Unable to join thread" );
             // NOTE: m_addr must be cleared before m_hndl is closed to avoid
             //       a race condition with isRunning. The operation is done
@@ -589,7 +601,7 @@ class Thread : ThreadBase
         }
         else version (Posix)
         {
-            if ( pthread_join( m_addr, null ) != 0 )
+            if ( m_addr != m_addr.init && pthread_join( m_addr, null ) != 0 )
                 throw new ThreadException( "Unable to join thread" );
             // NOTE: pthread_join acts as a substitute for pthread_detach,
             //       which is normally called by the dtor.  Setting m_addr
@@ -1396,8 +1408,78 @@ in (fn)
     void *sp = void;
     version (GNU)
     {
-        __builtin_unwind_init();
-        sp = &sp;
+        // The generic solution below using a call to __builtin_unwind_init ()
+        // followed by an assignment to sp has two issues:
+        // 1) On some archs it stores a huge amount of FP and Vector state which
+        //    is not the subject of the scan - and, indeed might produce false
+        //    hits.
+        // 2) Even on archs like X86, where there are no callee-saved FPRs/VRs there
+        //    tend to be 'holes' in the frame allocations (to deal with alignment) which
+        //    also will  contain random data which could produce false positives.
+        // This solution stores only the integer callee-saved registers.
+        version (X86)
+        {
+            void*[3] regs = void;
+            asm pure nothrow @nogc
+            {
+                "movl   %%ebx, %0" : "=m" (regs[0]);
+                "movl   %%esi, %0" : "=m" (regs[1]);
+                "movl   %%edi, %0" : "=m" (regs[2]);
+            }
+            sp = cast(void*)&regs[0];
+        }
+        else version (X86_64)
+        {
+            void*[5] regs = void;
+            asm pure nothrow @nogc
+            {
+                "movq   %%rbx, %0" : "=m" (regs[0]);
+                "movq   %%r12, %0" : "=m" (regs[1]);
+                "movq   %%r13, %0" : "=m" (regs[2]);
+                "movq   %%r14, %0" : "=m" (regs[3]);
+                "movq   %%r15, %0" : "=m" (regs[4]);
+            }
+            sp = cast(void*)&regs[0];
+        }
+        else version (PPC)
+        {
+            void*[19] regs = void;
+            version (Darwin)
+                enum regname = "r";
+            else
+                enum regname = "";
+            static foreach (i; 0 .. regs.length)
+            {{
+                enum int j = 13 + i; // source register
+                asm pure nothrow @nogc
+                {
+                    "stw "~regname~j.stringof~", %0" : "=m" (regs[i]);
+                }
+            }}
+            sp = cast(void*)&regs[0];
+        }
+        else version (PPC64)
+        {
+            void*[19] regs = void;
+            version (Darwin)
+                enum regname = "r";
+            else
+                enum regname = "";
+            static foreach (i; 0 .. regs.length)
+            {{
+                enum int j = 13 + i; // source register
+                asm pure nothrow @nogc
+                {
+                    "std "~regname~j.stringof~", %0" : "=m" (regs[i]);
+                }
+            }}
+            sp = cast(void*)&regs[0];
+        }
+        else
+        {
+            __builtin_unwind_init();
+            sp = &sp;
+        }
     }
     else version (AsmX86_Posix)
     {
@@ -1539,9 +1621,9 @@ package extern(D) void* getStackBottom() nothrow @nogc
             void *bottom;
 
             version (X86)
-                asm pure nothrow @nogc { "movl %%fs:4, %0;" : "=r" bottom; }
+                asm pure nothrow @nogc { "movl %%fs:4, %0;" : "=r" (bottom); }
             else version (X86_64)
-                asm pure nothrow @nogc { "movq %%gs:8, %0;" : "=r" bottom; }
+                asm pure nothrow @nogc { "movq %%gs:8, %0;" : "=r" (bottom); }
             else
                 static assert(false, "Platform not supported.");
 
@@ -1790,6 +1872,28 @@ private extern (D) bool suspend( Thread t ) nothrow @nogc
             t.m_reg[14] = state.lr;
             t.m_reg[15] = state.pc;
         }
+        else version (PPC)
+        {
+            ppc_thread_state_t state = void;
+            mach_msg_type_number_t count = PPC_THREAD_STATE_COUNT;
+
+            if (thread_get_state(t.m_tmach, PPC_THREAD_STATE, &state, &count) != KERN_SUCCESS)
+                onThreadError("Unable to load thread state");
+            if (!t.m_lock)
+                t.m_curr.tstack = cast(void*) state.r[1];
+            t.m_reg[] = state.r[];
+        }
+        else version (PPC64)
+        {
+            ppc_thread_state64_t state = void;
+            mach_msg_type_number_t count = PPC_THREAD_STATE64_COUNT;
+
+            if (thread_get_state(t.m_tmach, PPC_THREAD_STATE64, &state, &count) != KERN_SUCCESS)
+                onThreadError("Unable to load thread state");
+            if (!t.m_lock)
+                t.m_curr.tstack = cast(void*) state.r[1];
+            t.m_reg[] = state.r[];
+        }
         else
         {
             static assert(false, "Architecture not supported." );
@@ -2196,7 +2300,7 @@ else version (Posix)
             // before initilizing GC for TLS (rt_tlsgc_init)
             version (GNUShared)
             {
-                externDFunc!("gcc.sections.elf_shared.inheritLoadedLibraries",
+                externDFunc!("gcc.sections.inheritLoadedLibraries",
                              void function(void*) @nogc nothrow)(loadedLibraries);
             }
             else version (Shared)
@@ -2287,7 +2391,7 @@ else version (Posix)
                 rt_moduleTlsDtor();
                 version (GNUShared)
                 {
-                    externDFunc!("gcc.sections.elf_shared.cleanupLoadedLibraries",
+                    externDFunc!("gcc.sections.cleanupLoadedLibraries",
                                  void function() @nogc nothrow)();
                 }
                 else version (Shared)
@@ -2786,7 +2890,7 @@ private size_t adjustStackSize(size_t sz) nothrow @nogc
         // On glibc, TLS uses the top of the stack, so add its size to the requested size
         version (GNU)
         {
-            sz += externDFunc!("gcc.sections.elf_shared.sizeOfTLS",
+            sz += externDFunc!("gcc.sections.elf.sizeOfTLS",
                                size_t function() @nogc nothrow)();
         }
         else
diff --git a/libphobos/libdruntime/core/thread/threadbase.d b/libphobos/libdruntime/core/thread/threadbase.d
index c2c2333..0a8de10 100644
--- a/libphobos/libdruntime/core/thread/threadbase.d
+++ b/libphobos/libdruntime/core/thread/threadbase.d
@@ -10,6 +10,9 @@
  * Source:    $(DRUNTIMESRC core/thread/osthread.d)
  */
 
+/* NOTE: This file has been patched from the original DMD distribution to
+ * work with the GDC compiler.
+ */
 module core.thread.threadbase;
 
 import core.thread.context;
@@ -313,6 +316,7 @@ class ThreadBase
         // NOTE: This function may not be called until thread_init has
         //       completed.  See thread_suspendAll for more information
         //       on why this might occur.
+        version (GNU) pragma(inline, false);
         return sm_this;
     }
 
diff --git a/libphobos/libdruntime/gc/impl/conservative/gc.d b/libphobos/libdruntime/gc/impl/conservative/gc.d
index b7bb9b0..300a32a 100644
--- a/libphobos/libdruntime/gc/impl/conservative/gc.d
+++ b/libphobos/libdruntime/gc/impl/conservative/gc.d
@@ -76,7 +76,7 @@ debug(PRINTF_TO_FILE)
                 gcStartTick = MonoTime.currTime;
             immutable timeElapsed = MonoTime.currTime - gcStartTick;
             immutable secondsAsDouble = timeElapsed.total!"hnsecs" / cast(double)convert!("seconds", "hnsecs")(1);
-            len = fprintf(gcx_fh, "%10.6lf: ", secondsAsDouble);
+            len = fprintf(gcx_fh, "%10.6f: ", secondsAsDouble);
         }
         len += fprintf(gcx_fh, fmt, args);
         fflush(gcx_fh);
@@ -159,7 +159,7 @@ debug (LOGGING)
             printf("    p = %p, size = %zd, parent = %p ", p, size, parent);
             if (file)
             {
-                printf("%s(%u)", file, line);
+                printf("%s(%u)", file, cast(uint)line);
             }
             printf("\n");
         }
diff --git a/libphobos/libdruntime/gcc/attribute.d b/libphobos/libdruntime/gcc/attribute.d
index fc90d2a..d1ff5c7 100644
--- a/libphobos/libdruntime/gcc/attribute.d
+++ b/libphobos/libdruntime/gcc/attribute.d
@@ -20,14 +20,7 @@
 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 // <http://www.gnu.org/licenses/>.
 
+deprecated("Import gcc.attributes instead")
 module gcc.attribute;
 
-private struct Attribute(A...)
-{
-    A args;
-}
-
-auto attribute(A...)(A args) if (A.length > 0 && is(A[0] == string))
-{
-    return Attribute!A(args);
-}
+public import gcc.attributes;
diff --git a/libphobos/libdruntime/gcc/attributes.d b/libphobos/libdruntime/gcc/attributes.d
new file mode 100644
index 0000000..58a4023
--- /dev/null
+++ b/libphobos/libdruntime/gcc/attributes.d
@@ -0,0 +1,605 @@
+// GNU D Compiler attribute support declarations.
+// Copyright (C) 2021 Free Software Foundation, Inc.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+module gcc.attributes;
+
+// Private helper templates.
+private struct Attribute(A...)
+{
+    A arguments;
+}
+
+private enum bool isStringValue(alias T) = is(typeof(T) == string);
+
+private enum bool isStringOrIntValue(alias T)
+    = is(typeof(T) == string) || is(typeof(T) == int);
+
+private template allSatisfy(alias F, T...)
+{
+    static if (T.length == 0)
+        enum allSatisfy = true;
+    else static if (T.length == 1)
+        enum allSatisfy = F!(T[0]);
+    else
+    {
+        enum allSatisfy = allSatisfy!(F, T[ 0  .. $/2])
+            && allSatisfy!(F, T[$/2 ..  $ ]);
+    }
+}
+
+/**
+ * Generic entrypoint for applying GCC attributes to a function or type.
+ * There is no type checking done, as well as no deprecation path for
+ * attributes removed from the compiler.  So the recommendation is to use any
+ , of the other UDAs available unless it is a target-specific attribute.
+ *
+ * Function attributes introduced by the @attribute UDA are used in the
+ * declaration of a function, followed by an attribute name string and
+ * any arguments separated by commas enclosed in parentheses.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @attribute("regparm", 1) int func(int size);
+ * ---
+ */
+@system
+auto attribute(A...)(A arguments)
+    if (A.length > 0 && is(A[0] == string))
+{
+    return Attribute!A(arguments);
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// Supported common attributes exposed by GDC.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+/**
+ * The `@alloc_size` attribute may be applied to a function that returns a
+ * pointer and takes at least one argument of an integer or enumerated type.
+ * It indicates that the returned pointer points to memory whose size is given
+ * by the function argument at `sizeArgIdx`, or by the product of the arguments
+ * at `sizeArgIdx` and `numArgIdx`.  Meaningful sizes are positive values less
+ * than `ptrdiff_t.max`.  Unless `zeroBasedNumbering` is true, argument
+ * numbering starts at one for ordinary functions, and at two for non-static
+ * member functions.
+ *
+ * If `numArgIdx` is less than `0`, it is taken to mean there is no argument
+ * specifying the element count.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @alloc_size(1) extern(C) void* malloc(size_t size);
+ * @alloc_size(3,2) extern(C) void* reallocarray(void *ptr, size_t nmemb,
+ *                                               size_t size);
+ * @alloc_size(1,2) void* my_calloc(size_t element_size, size_t count,
+ *                                  bool irrelevant);
+ * ---
+ */
+auto alloc_size(int sizeArgIdx)
+{
+    return attribute("alloc_size", sizeArgIdx);
+}
+
+/// ditto
+auto alloc_size(int sizeArgIdx, int numArgIdx)
+{
+    return attribute("alloc_size", sizeArgIdx, numArgIdx);
+}
+
+/// ditto
+auto alloc_size(int sizeArgIdx, int numArgIdx, bool zeroBasedNumbering)
+{
+    return attribute("alloc_size", sizeArgIdx, numArgIdx, zeroBasedNumbering);
+}
+
+auto alloc_size(A...)(A arguments)
+{
+    assert(false, "alloc_size attribute argument value is not an integer constant");
+}
+
+/**
+ * The `@always_inline` attribute inlines the function independent of any
+ * restrictions that otherwise apply to inlining.  Failure to inline such a
+ * function is diagnosed as an error.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @always_inline int func();
+ * ---
+ */
+enum always_inline = attribute("always_inline");
+
+/**
+ * The `@cold` attribute on functions is used to inform the compiler that the
+ * function is unlikely to be executed.  The function is optimized for size
+ * rather than speed and on many targets it is placed into a special subsection
+ * of the text section so all cold functions appear close together, improving
+ * code locality of non-cold parts of program.  The paths leading to calls of
+ * cold functions within code are considered to be cold too.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @cold int func();
+ * ---
+ */
+enum cold = attribute("cold");
+
+/**
+ * The `@flatten` attribute is used to inform the compiler that every call
+ * inside this function should be inlined, if possible.  Functions declared with
+ * attribute `@noinline` and similar are not inlined.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @flatten int func();
+ * ---
+ */
+enum flatten = attribute("flatten");
+
+/**
+ * The `@no_icf` attribute prevents a functions from being merged with another
+ * semantically equivalent function.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @no_icf int func();
+ * ---
+ */
+enum no_icf = attribute("no_icf");
+
+/**
+ * The `@noclone` attribute prevents a function from being considered for
+ * cloning - a mechanism that produces specialized copies of functions and
+ * which is (currently) performed by interprocedural constant propagation.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @noclone int func();
+ * ---
+ */
+enum noclone = attribute("noclone");
+
+/**
+ * The `@noinline` attribute prevents a function from being considered for
+ * inlining.  If the function does not have side effects, there are
+ * optimizations other than inlining that cause function calls to be optimized
+ * away, although the function call is live.  To keep such calls from being
+ * optimized away, put `asm { ""; }` in the called function, to serve as a
+ * special side effect.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @noinline int func();
+ * ---
+ */
+enum noinline = attribute("noinline");
+
+/**
+ * The `@noipa` attribute disables interprocedural optimizations between the
+ * function with this attribute and its callers, as if the body of the function
+ * is not available when optimizing callers and the callers are unavailable when
+ * optimizing the body.  This attribute implies `@noinline`, `@noclone`, and
+ * `@no_icf` attributes.  However, this attribute is not equivalent to a
+ * combination of other attributes, because its purpose is to suppress existing
+ * and future optimizations employing interprocedural analysis, including those
+ * that do not have an attribute suitable for disabling them individually.
+ *
+ * This attribute is supported mainly for the purpose of testing the compiler.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @noipa int func();
+ * ---
+ */
+enum noipa = attribute("noipa");
+
+/**
+ * The `@optimize` attribute is used to specify that a function is to be
+ * compiled with different optimization options than specified on the command
+ * line.  Valid `arguments` are constant non-negative integers and strings.
+ * Multiple arguments can be provided, separated by commas to specify multiple
+ * options.  Each numeric argument specifies an optimization level.  Each string
+ * argument that begins with the letter O refers to an optimization option such
+ * as `-O0` or `-Os`.  Other options are taken as suffixes to the `-f` prefix
+ * jointly forming the name of an optimization option.
+ *
+ * Not every optimization option that starts with the `-f` prefix specified by
+ * the attribute necessarily has an effect on the function.  The `@optimize`
+ * attribute should be used for debugging purposes only.  It is not suitable in
+ * production code.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @optimize(2) double fn0(double x);
+ * @optimize("2") double fn1(double x);
+ * @optimize("s") double fn2(double x);
+ * @optimize("Ofast") double fn3(double x);
+ * @optimize("-O2") double fn4(double x);
+ * @optimize("tree-vectorize") double fn5(double x);
+ * @optimize("-ftree-vectorize") double fn6(double x);
+ * @optimize("no-finite-math-only", 3) double fn7(double x);
+ * ---
+ */
+auto optimize(A...)(A arguments)
+    if (allSatisfy!(isStringOrIntValue, arguments))
+{
+    return attribute("optimize", arguments);
+}
+
+auto optimize(A...)(A arguments)
+    if (!allSatisfy!(isStringOrIntValue, arguments))
+{
+    assert(false, "optimize attribute argument not a string or integer constant");
+}
+
+/**
+ * The `@restrict` attribute specifies that a function parameter is to be
+ * restrict-qualified in the C99 sense of the term.  The parameter needs to
+ * boil down to either a pointer or reference type, such as a D pointer,
+ * class reference, or a `ref` parameter.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * void func(@restrict ref const float[16] array);
+ * ---
+ */
+enum restrict = attribute("restrict");
+
+/**
+ * The `@section` attribute specifies that a function lives in a particular
+ * section.  For when you need certain particular functions to appear in
+ * special sections.
+ *
+ * Some file formats do not support arbitrary sections so the section attribute
+ * is not available on all platforms.  If you need to map the entire contents
+ * of a module to a particular section, consider using the facilities of the
+ * linker instead.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @section("bar") extern void func();
+ * ---
+ */
+auto section(string sectionName)
+{
+    return attribute("section", sectionName);
+}
+
+auto section(A...)(A arguments)
+{
+    assert(false, "section attribute argument not a string constant");
+}
+
+/**
+ * The `@symver` attribute creates a symbol version on ELF targets.  The syntax
+ * of the string parameter is `name@nodename`.  The `name` part of the parameter
+ * is the actual name of the symbol by which it will be externally referenced.
+ * The `nodename` portion should be the name of a node specified in the version
+ * script supplied to the linker when building a shared library.  Versioned
+ * symbol must be defined and must be exported with default visibility.
+ *
+ * Finally if the parameter is `name@@nodename` then in addition to creating a
+ * symbol version (as if `name@nodename` was used) the version will be also used
+ * to resolve `name` by the linker.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @symver("foo@VERS_1") int foo_v1();
+ * ---
+ */
+auto symver(A...)(A arguments)
+    if (allSatisfy!(isStringValue, arguments))
+{
+    return attribute("symver", arguments);
+}
+
+auto symver(A...)(A arguments)
+    if (!allSatisfy!(isStringValue, arguments))
+{
+    assert(false, "symver attribute argument not a string constant");
+}
+
+/**
+ * The `@target` attribute is used to specify that a function is to be
+ * compiled with different target options than specified on the command line.
+ * One or more strings can be provided as arguments, separated by commas to
+ * specify multiple options.  Each string consists of one or more
+ * comma-separated suffixes to the `-m` prefix jointly forming the name of a
+ * machine-dependent option.
+ *
+ * The target attribute can be used for instance to have a function compiled
+ * with a different ISA (instruction set architecture) than the default.
+ *
+ * The options supported are specific to each target.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @target("arch=core2") void core2_func();
+ * @target("sse3") void sse3_func();
+ * ---
+ */
+auto target(A...)(A arguments)
+    if (allSatisfy!(isStringValue, arguments))
+{
+    return attribute("target", arguments);
+}
+
+auto target(A...)(A arguments)
+    if (!allSatisfy!(isStringValue, arguments))
+{
+    assert(false, "target attribute argument not a string constant");
+}
+
+/**
+ * The `@target_clones` attribute is used to specify that a function be cloned
+ * into multiple versions compiled with different target `options` than
+ * specified on the command line.  The supported options and restrictions are
+ * the same as for `@target` attribute.
+ *
+ * It also creates a resolver function that dynamically selects a clone suitable
+ * for current architecture.  The resolver is created only if there is a usage
+ * of a function with `@target_clones` attribute.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @target_clones("sse4.1,avx,default") double func(double x);
+ * ---
+ */
+auto target_clones(A...)(A arguments)
+    if (allSatisfy!(isStringValue, arguments))
+{
+    return attribute("target_clones", arguments);
+}
+
+auto target_clones(A...)(A arguments)
+    if (!allSatisfy!(isStringValue, arguments))
+{
+    assert(false, "target attribute argument not a string constant");
+}
+
+/**
+ * The `@used` attribute, annotated to a function, means that code must be
+ * emitted for the function even if it appears that the function is not
+ * referenced.  This is useful, for example, when the function is referenced
+ * only in inline assembly.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @used __gshared int var = 0x1000;
+ * ---
+ */
+enum used = attribute("used");
+
+/**
+ * The `@weak` attribute causes a declaration of an external symbol to be
+ * emitted as a weak symbol rather than a global.  This is primarily useful in
+ * defining library functions that can be overridden in user code, though it can
+ * also be used with non-function declarations.  The overriding symbol must have
+ * the same type as the weak symbol.  In addition, if it designates a variable
+ * it must also have the same size and alignment as the weak symbol.
+ *
+ * Weak symbols are supported for ELF targets, and also for a.out targets when
+ * using the GNU assembler and linker.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @weak int func() { return 1; }
+ * ---
+ */
+enum weak = attribute("weak");
+
+/**
+ * The `@noplt` attribute is the counterpart to option `-fno-plt`. Calls to
+ * functions marked with this attribute in position-independent code do not use
+ * the PLT in position-independent code.
+ *
+ * In position-dependant code, a few targets also convert call to functions
+ * that are marked to not use the PLT to use the GOT instead.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @noplt int func();
+ *
+ * ---
+ */
+enum noplt = attribute("noplt");
+
+///////////////////////////////////////////////////////////////////////////////
+//
+// Attributes defined for compatibility with LDC.
+//
+///////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Specifies that the function returns `null` or a pointer to at least a
+ * certain number of allocated bytes. `sizeArgIdx` and `numArgIdx` specify
+ * the 0-based index of the function arguments that should be used to calculate
+ * the number of bytes returned.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @allocSize(0) extern(C) void* malloc(size_t size);
+ * @allocSize(2,1) extern(C) void* reallocarray(void *ptr, size_t nmemb,
+ *                                              size_t size);
+ * @allocSize(0,1) void* my_calloc(size_t element_size, size_t count,
+ *                                 bool irrelevant);
+ * ---
+ */
+auto allocSize(int sizeArgIdx, int numArgIdx = int.min)
+{
+    return alloc_size(sizeArgIdx, numArgIdx, true);
+}
+
+auto allocSize(A...)(A arguments)
+{
+    assert(false, "allocSize attribute argument value is not an integer constant");
+}
+
+/**
+ * When applied to a global symbol, the compiler, assembler, and linker are
+ * required to treat the symbol as if there is a reference to the symbol that
+ * it cannot see (which is why they have to be named).  For example, it
+ * prevents the deletion by the linker of an unreferenced symbol.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @assumeUsed __gshared int var = 0x1000;
+ * ---
+ */
+alias assumeUsed = used;
+
+/// This attribute has no effect.
+enum dynamicCompile = false;
+
+/// ditto
+enum dynamicCompileConst = false;
+
+/// ditto
+enum dynamicCompileEmit = false;
+
+/**
+ * Explicitly sets "fast-math" for a function, enabling aggressive math
+ * optimizations.  These optimizations may dramatically change the outcome of
+ * floating point calculations (e.g. because of reassociation).
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @fastmath
+ * double dot(double[] a, double[] b) {
+ *     double s = 0;
+ *     foreach(size_t i; 0..a.length)
+ *     {
+ *         // will result in vectorized fused-multiply-add instructions
+ *         s += a * b;
+ *     }
+ *     return s;
+ * }
+ * ---
+ */
+enum fastmath = optimize("Ofast");
+
+/**
+ * Adds GCC's "naked" attribute to a function, disabling function prologue /
+ * epilogue emission.
+ * Intended to be used in combination with basic `asm` statement.  While using
+ * extended `asm` or a mixture of basic `asm` and D code may appear to work,
+ * they cannot be depended upon to work reliably and are not supported.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @naked void abort() {
+ *     asm { "ud2"; }
+ * }
+ * ---
+ */
+enum naked = attribute("naked");
+
+/**
+ * Sets the optimization strategy for a function.
+ * Valid strategies are "none", "optsize", "minsize". The strategies are
+ * mutually exclusive.
+ *
+ * Example:
+ * ---
+ * import gcc.attributes;
+ *
+ * @optStrategy("none")
+ * int func() {
+ *     return call();
+ * }
+ * ---
+ */
+auto optStrategy(string strategy)
+{
+    if (strategy == "none")
+        return optimize("O0");
+    else if (strategy == "optsize" || strategy == "minsize")
+        return optimize("Os");
+    else
+    {
+        assert(false, "unrecognized parameter `" ~ strategy
+               ~ "` for `gcc.attribute.optStrategy`");
+    }
+}
+
+auto optStrategy(A...)(A arguments)
+{
+    assert(false, "optStrategy attribute argument value is not a string constant");
+}
+
+/**
+ * When applied to a function, specifies that the function should be optimzed
+ * by Graphite, GCC's polyhedral optimizer. Useful for optimizing loops for
+ * data locality, vectorization and parallelism.
+ *
+ * Experimental!
+ *
+ * Only effective when GDC was built with ISL included.
+ */
+enum polly = optimize("loop-parallelize-all", "loop-nest-optimize");
diff --git a/libphobos/libdruntime/gcc/backtrace.d b/libphobos/libdruntime/gcc/backtrace.d
index 45dd011..8f5582d 100644
--- a/libphobos/libdruntime/gcc/backtrace.d
+++ b/libphobos/libdruntime/gcc/backtrace.d
@@ -424,8 +424,10 @@ private:
         import core.sys.freebsd.dlfcn;
     else version (NetBSD)
         import core.sys.netbsd.dlfcn;
+    else version (OpenBSD)
+        import core.sys.openbsd.dlfcn;
     else version (Solaris)
-        import core.sys.netbsd.dlfcn;
+        import core.sys.solaris.dlfcn;
     else version (Posix)
         import core.sys.posix.dlfcn;
 
diff --git a/libphobos/libdruntime/gcc/deh.d b/libphobos/libdruntime/gcc/deh.d
index c747b51..eb83751c 100644
--- a/libphobos/libdruntime/gcc/deh.d
+++ b/libphobos/libdruntime/gcc/deh.d
@@ -28,17 +28,12 @@ import gcc.unwind;
 import gcc.unwind.pe;
 import gcc.builtins;
 import gcc.config;
-import gcc.attribute;
+import gcc.attributes;
 
 extern(C)
 {
     int _d_isbaseof(ClassInfo, ClassInfo);
     void _d_createTrace(Object, void*);
-
-    // Not used in GDC but declaration required by rt/sections.d
-    struct FuncTable
-    {
-    }
 }
 
 /**
@@ -552,7 +547,7 @@ _Unwind_Reason_Code scanLSDA(const(ubyte)* lsda, _Unwind_Exception_Class excepti
     _Unwind_Ptr LPStart = 0;
 
     if (LPStartEncoding != DW_EH_PE_omit)
-        LPStart = read_encoded_value(context, LPStartEncoding, &p);
+        LPStart = read_encoded_value(context, LPStartEncoding, p);
     else
         LPStart = Start;
 
@@ -568,14 +563,14 @@ _Unwind_Reason_Code scanLSDA(const(ubyte)* lsda, _Unwind_Exception_Class excepti
             // hardcoded OS-specific format.
             TTypeEncoding = _TTYPE_ENCODING;
         }
-        auto TTbase = read_uleb128(&p);
+        auto TTbase = read_uleb128(p);
         TType = p + TTbase;
     }
 
     // The encoding and length of the call-site table; the action table
     // immediately follows.
     ubyte CSEncoding = *p++;
-    auto CSTableSize = read_uleb128(&p);
+    auto CSTableSize = read_uleb128(p);
     const(ubyte)* actionTable = p + CSTableSize;
 
     auto TTypeBase = base_of_encoded_value(TTypeEncoding, context);
@@ -613,8 +608,8 @@ _Unwind_Reason_Code scanLSDA(const(ubyte)* lsda, _Unwind_Exception_Class excepti
             _uleb128_t CSLandingPad, CSAction;
             do
             {
-                CSLandingPad = read_uleb128(&p);
-                CSAction = read_uleb128(&p);
+                CSLandingPad = read_uleb128(p);
+                CSAction = read_uleb128(p);
             }
             while (--ip);
 
@@ -631,10 +626,10 @@ _Unwind_Reason_Code scanLSDA(const(ubyte)* lsda, _Unwind_Exception_Class excepti
         while (p < actionTable)
         {
             // Note that all call-site encodings are "absolute" displacements.
-            auto CSStart = read_encoded_value(null, CSEncoding, &p);
-            auto CSLen = read_encoded_value(null, CSEncoding, &p);
-            auto CSLandingPad = read_encoded_value(null, CSEncoding, &p);
-            auto CSAction = read_uleb128(&p);
+            auto CSStart = read_encoded_value(null, CSEncoding, p);
+            auto CSLen = read_encoded_value(null, CSEncoding, p);
+            auto CSLandingPad = read_encoded_value(null, CSEncoding, p);
+            auto CSAction = read_uleb128(p);
 
             // The table is sorted, so if we've passed the ip, stop.
             if (ip < Start + CSStart)
@@ -708,9 +703,9 @@ int actionTableLookup(_Unwind_Action actions, _Unwind_Exception* unwindHeader,
     while (1)
     {
         auto ap = actionRecord;
-        auto ARFilter = read_sleb128(&ap);
+        auto ARFilter = read_sleb128(ap);
         auto apn = ap;
-        auto ARDisp = read_sleb128(&ap);
+        auto ARDisp = read_sleb128(ap);
 
         if (ARFilter == 0)
         {
@@ -730,7 +725,7 @@ int actionTableLookup(_Unwind_Action actions, _Unwind_Exception* unwindHeader,
             // the ClassInfo is stored.
             const(ubyte)* tp = TType - ARFilter * encodedSize;
 
-            auto entry = read_encoded_value_with_base(TTypeEncoding, TTypeBase, &tp);
+            auto entry = read_encoded_value_with_base(TTypeEncoding, TTypeBase, tp);
             ClassInfo ci = cast(ClassInfo)cast(void*)(entry);
 
             // D does not have catch-all handlers, and so the following
@@ -805,7 +800,7 @@ version (GNU_SEH_Exceptions)
                                                            void* ms_orig_context, void* ms_disp)
     {
         return _GCC_specific_handler(ms_exc, this_frame, ms_orig_context,
-                                     ms_disp, &__gdc_personality_imp);
+                                     ms_disp, &gdc_personality);
     }
 }
 else version (GNU_SjLj_Exceptions)
diff --git a/libphobos/libdruntime/gcc/gthread.d b/libphobos/libdruntime/gcc/gthread.d
index ef35a3c27..5003637 100644
--- a/libphobos/libdruntime/gcc/gthread.d
+++ b/libphobos/libdruntime/gcc/gthread.d
@@ -86,10 +86,12 @@ else static if (GNU_Thread_Model == ThreadModel.Single)
 }
 else static if (GNU_Thread_Model == ThreadModel.Win32)
 {
+    import core.stdc.config;
+
     struct __gthread_once_t
     {
-        INT done;
-        LONG started;
+        int done;
+        c_long started;
     }
 
     int __gthr_win32_key_create(__gthread_key_t* keyp, GthreadDestroyFn dtor);
diff --git a/libphobos/libdruntime/gcc/sections/android.d b/libphobos/libdruntime/gcc/sections/android.d
deleted file mode 100644
index 4af26b4..0000000
--- a/libphobos/libdruntime/gcc/sections/android.d
+++ /dev/null
@@ -1,184 +0,0 @@
-// Bionic-specific support for sections.
-// Copyright (C) 2019-2021 Free Software Foundation, Inc.
-
-// GCC is free software; you can redistribute it and/or modify it under
-// the terms of the GNU General Public License as published by the Free
-// Software Foundation; either version 3, or (at your option) any later
-// version.
-
-// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
-// WARRANTY; without even the implied warranty of MERCHANTABILITY or
-// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-// for more details.
-
-// Under Section 7 of GPL version 3, you are granted additional
-// permissions described in the GCC Runtime Library Exception, version
-// 3.1, as published by the Free Software Foundation.
-
-// You should have received a copy of the GNU General Public License and
-// a copy of the GCC Runtime Library Exception along with this program;
-// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
-// <http://www.gnu.org/licenses/>.
-
-module gcc.sections.android;
-
-version (CRuntime_Bionic):
-
-// debug = PRINTF;
-debug(PRINTF) import core.stdc.stdio;
-import core.stdc.stdlib : malloc, free;
-import rt.deh, rt.minfo;
-import core.sys.posix.pthread;
-import core.stdc.stdlib : calloc;
-import core.stdc.string : memcpy;
-
-struct SectionGroup
-{
-    static int opApply(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    static int opApplyReverse(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
-    {
-        return _moduleGroup.modules;
-    }
-
-    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
-    {
-        return _moduleGroup;
-    }
-
-    @property immutable(FuncTable)[] ehTables() const nothrow @nogc
-    {
-        auto pbeg = cast(immutable(FuncTable)*)&__start_deh;
-        auto pend = cast(immutable(FuncTable)*)&__stop_deh;
-        return pbeg[0 .. pend - pbeg];
-    }
-
-    @property inout(void[])[] gcRanges() inout nothrow @nogc
-    {
-        return _gcRanges[];
-    }
-
-private:
-    ModuleGroup _moduleGroup;
-    void[][1] _gcRanges;
-}
-
-void initSections() nothrow @nogc
-{
-    pthread_key_create(&_tlsKey, null);
-
-    auto mbeg = cast(immutable ModuleInfo**)&__start_minfo;
-    auto mend = cast(immutable ModuleInfo**)&__stop_minfo;
-    _sections.moduleGroup = ModuleGroup(mbeg[0 .. mend - mbeg]);
-
-    auto pbeg = cast(void*)&_tlsend;
-    auto pend = cast(void*)&__bss_end__;
-    // _tlsend is a 32-bit int and may not be 64-bit void*-aligned, so align pbeg.
-    version (D_LP64) pbeg = cast(void*)(cast(size_t)(pbeg + 7) & ~cast(size_t)7);
-    _sections._gcRanges[0] = pbeg[0 .. pend - pbeg];
-}
-
-void finiSections() nothrow @nogc
-{
-    pthread_key_delete(_tlsKey);
-}
-
-void[]* initTLSRanges() nothrow @nogc
-{
-    return &getTLSBlock();
-}
-
-void finiTLSRanges(void[]* rng) nothrow @nogc
-{
-    .free(rng.ptr);
-    .free(rng);
-}
-
-void scanTLSRanges(void[]* rng, scope void delegate(void* pbeg, void* pend) nothrow dg) nothrow
-{
-    dg(rng.ptr, rng.ptr + rng.length);
-}
-
-/* NOTE: The Bionic C library ignores thread-local data stored in the normal
- *       .tbss/.tdata ELF sections, which are marked with the SHF_TLS/STT_TLS
- *       flags.  So instead we roll our own by keeping TLS data in the
- *       .tdata/.tbss sections but removing the SHF_TLS/STT_TLS flags, and
- *       access the TLS data using this function and the _tlsstart/_tlsend
- *       symbols as delimiters.
- *
- *       This function is called by the code emitted by the compiler.  It
- *       is expected to translate an address in the TLS static data to
- *       the corresponding address in the TLS dynamic per-thread data.
- */
-
-extern(C) void* __tls_get_addr( void* p ) nothrow @nogc
-{
-    debug(PRINTF) printf("  __tls_get_addr input - %p\n", p);
-    immutable offset = cast(size_t)(p - cast(void*)&_tlsstart);
-    auto tls = getTLSBlockAlloc();
-    assert(offset < tls.length);
-    return tls.ptr + offset;
-}
-
-private:
-
-__gshared pthread_key_t _tlsKey;
-
-ref void[] getTLSBlock() nothrow @nogc
-{
-    auto pary = cast(void[]*)pthread_getspecific(_tlsKey);
-    if (pary is null)
-    {
-        pary = cast(void[]*).calloc(1, (void[]).sizeof);
-        if (pthread_setspecific(_tlsKey, pary) != 0)
-        {
-            import core.stdc.stdio;
-            perror("pthread_setspecific failed with");
-            assert(0);
-        }
-    }
-    return *pary;
-}
-
-ref void[] getTLSBlockAlloc() nothrow @nogc
-{
-    auto pary = &getTLSBlock();
-    if (!pary.length)
-    {
-        auto pbeg = cast(void*)&_tlsstart;
-        auto pend = cast(void*)&_tlsend;
-        auto p = .malloc(pend - pbeg);
-        memcpy(p, pbeg, pend - pbeg);
-        *pary = p[0 .. pend - pbeg];
-    }
-    return *pary;
-}
-
-__gshared SectionGroup _sections;
-
-extern(C)
-{
-    /* Symbols created by the compiler/linker and inserted into the
-     * object file that 'bracket' sections.
-     */
-    extern __gshared
-    {
-        void* __start_deh;
-        void* __stop_deh;
-        void* __start_minfo;
-        void* __stop_minfo;
-
-        size_t __bss_end__;
-
-        int _tlsstart;
-        int _tlsend;
-    }
-}
diff --git a/libphobos/libdruntime/gcc/sections/common.d b/libphobos/libdruntime/gcc/sections/common.d
new file mode 100644
index 0000000..85fdc0e
--- /dev/null
+++ b/libphobos/libdruntime/gcc/sections/common.d
@@ -0,0 +1,39 @@
+// Contains various utility functions used by the runtime implementation.
+// Copyright (C) 2019-2021 Free Software Foundation, Inc.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+module gcc.sections.common;
+
+/**
+ * Asserts that the given condition is `true`.
+ *
+ * The assertion is independent from -release, by abort()ing. Regular assertions
+ * throw an AssertError and thus require an initialized GC, which might not be
+ * the case (yet or anymore) for the startup/shutdown code in this package
+ * (called by CRT ctors/dtors etc.).
+ */
+package(gcc) void safeAssert(
+    bool condition, scope string msg, scope string file = __FILE__, size_t line = __LINE__
+) nothrow @nogc @safe
+{
+    import core.internal.abort;
+    condition || abort(msg, file, line);
+}
diff --git a/libphobos/libdruntime/gcc/sections/elf_shared.d b/libphobos/libdruntime/gcc/sections/elf.d
index 5b0fad9..3480fb9 100644
--- a/libphobos/libdruntime/gcc/sections/elf_shared.d
+++ b/libphobos/libdruntime/gcc/sections/elf.d
@@ -20,7 +20,7 @@
 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 // <http://www.gnu.org/licenses/>.
 
-module gcc.sections.elf_shared;
+module gcc.sections.elf;
 
 version (MIPS32)  version = MIPS_Any;
 version (MIPS64)  version = MIPS_Any;
@@ -33,13 +33,13 @@ version (CRuntime_Glibc) enum SharedELF = true;
 else version (CRuntime_Musl) enum SharedELF = true;
 else version (FreeBSD) enum SharedELF = true;
 else version (NetBSD) enum SharedELF = true;
+else version (OpenBSD) enum SharedELF = true;
 else version (DragonFlyBSD) enum SharedELF = true;
 else version (CRuntime_UClibc) enum SharedELF = true;
 else version (Solaris) enum SharedELF = true;
 else enum SharedELF = false;
 static if (SharedELF):
 
-// debug = PRINTF;
 import core.memory;
 import core.stdc.config;
 import core.stdc.stdio;
@@ -63,6 +63,12 @@ else version (NetBSD)
     import core.sys.netbsd.sys.elf;
     import core.sys.netbsd.sys.link_elf;
 }
+else version (OpenBSD)
+{
+    import core.sys.openbsd.dlfcn;
+    import core.sys.openbsd.sys.elf;
+    import core.sys.openbsd.sys.link_elf;
+}
 else version (DragonFlyBSD)
 {
     import core.sys.dragonflybsd.dlfcn;
@@ -81,25 +87,14 @@ else
     static assert(0, "unimplemented");
 }
 import core.sys.posix.pthread;
-import gcc.builtins;
-import gcc.config;
 import rt.deh;
 import rt.dmain2;
 import rt.minfo;
 import rt.util.container.array;
 import rt.util.container.hashtab;
-
-/****
- * Asserts the specified condition, independent from -release, by abort()ing.
- * Regular assertions throw an AssertError and thus require an initialized
- * GC, which isn't the case (yet or anymore) for the startup/shutdown code in
- * this module (called by CRT ctors/dtors etc.).
- */
-private void safeAssert(bool condition, scope string msg, size_t line = __LINE__) @nogc nothrow @safe
-{
-    import core.internal.abort;
-    condition || abort(msg, __FILE__, line);
-}
+import gcc.builtins;
+import gcc.config;
+import gcc.sections.common;
 
 alias DSO SectionGroup;
 struct DSO
@@ -134,11 +129,6 @@ struct DSO
         return _moduleGroup;
     }
 
-    @property immutable(FuncTable)[] ehTables() const nothrow @nogc
-    {
-        return null;
-    }
-
     @property inout(void[])[] gcRanges() inout nothrow @nogc
     {
         return _gcRanges[];
@@ -177,22 +167,12 @@ private:
 __gshared bool _isRuntimeInitialized;
 
 
-version (FreeBSD) private __gshared void* dummy_ref;
-version (DragonFlyBSD) private __gshared void* dummy_ref;
-version (NetBSD) private __gshared void* dummy_ref;
-version (Solaris) private __gshared void* dummy_ref;
-
 /****
  * Gets called on program startup just before GC is initialized.
  */
 void initSections() nothrow @nogc
 {
     _isRuntimeInitialized = true;
-    // reference symbol to support weak linkage
-    version (FreeBSD) dummy_ref = &_d_dso_registry;
-    version (DragonFlyBSD) dummy_ref = &_d_dso_registry;
-    version (NetBSD) dummy_ref = &_d_dso_registry;
-    version (Solaris) dummy_ref = &_d_dso_registry;
 }
 
 
@@ -208,6 +188,9 @@ alias ScanDG = void delegate(void* pbeg, void* pend) nothrow;
 
 version (Shared)
 {
+    import gcc.sections : pinLoadedLibraries, unpinLoadedLibraries,
+           inheritLoadedLibraries, cleanupLoadedLibraries;
+
     /***
      * Called once per thread; returns array of thread local storage ranges
      */
@@ -248,6 +231,7 @@ version (Shared)
     }
 
     // interface for core.thread to inherit loaded libraries
+    pragma(mangle, gcc.sections.pinLoadedLibraries.mangleof)
     void* pinLoadedLibraries() nothrow @nogc
     {
         auto res = cast(Array!(ThreadDSO)*)calloc(1, Array!(ThreadDSO).sizeof);
@@ -266,6 +250,7 @@ version (Shared)
         return res;
     }
 
+    pragma(mangle, gcc.sections.unpinLoadedLibraries.mangleof)
     void unpinLoadedLibraries(void* p) nothrow @nogc
     {
         auto pary = cast(Array!(ThreadDSO)*)p;
@@ -285,6 +270,7 @@ version (Shared)
 
     // Called before TLS ctors are ran, copy over the loaded libraries
     // of the parent thread.
+    pragma(mangle, gcc.sections.inheritLoadedLibraries.mangleof)
     void inheritLoadedLibraries(void* p) nothrow @nogc
     {
         safeAssert(_loadedDSOs.empty, "DSOs have already been registered for this thread.");
@@ -298,6 +284,7 @@ version (Shared)
     }
 
     // Called after all TLS dtors ran, decrements all remaining dlopen refs.
+    pragma(mangle, gcc.sections.cleanupLoadedLibraries.mangleof)
     void cleanupLoadedLibraries() nothrow @nogc
     {
         foreach (ref tdso; _loadedDSOs)
@@ -403,12 +390,6 @@ version (Shared)
      */
     __gshared pthread_mutex_t _handleToDSOMutex;
     @property ref HashTab!(void*, DSO*) _handleToDSO() @nogc nothrow { __gshared HashTab!(void*, DSO*) x; return x; }
-
-    /*
-     * Section in executable that contains copy relocations.
-     * Might be null when druntime is dynamically loaded by a C host.
-     */
-    __gshared const(void)[] _copyRelocSection;
 }
 else
 {
@@ -714,20 +695,22 @@ version (Shared)
 @nogc nothrow:
     link_map* linkMapForHandle(void* handle)
     {
-        link_map* map;
-        const success = dlinfo(handle, RTLD_DI_LINKMAP, &map) == 0;
-        safeAssert(success, "Failed to get DSO info.");
-        return map;
+        static if (__traits(compiles, RTLD_DI_LINKMAP))
+        {
+            link_map* map;
+            const success = dlinfo(handle, RTLD_DI_LINKMAP, &map) == 0;
+            safeAssert(success, "Failed to get DSO info.");
+            return map;
+        }
+        else version (OpenBSD)
+        {
+            safeAssert(handle !is null, "Failed to get DSO info.");
+            return cast(link_map*)handle;
+        }
+        else
+            static assert(0, "unimplemented");
     }
 
-     link_map* exeLinkMap(link_map* map)
-     {
-         safeAssert(map !is null, "Invalid link_map.");
-         while (map.l_prev !is null)
-             map = map.l_prev;
-         return map;
-     }
-
     DSO* dsoForHandle(void* handle)
     {
         DSO* pdso;
@@ -792,6 +775,8 @@ version (Shared)
                     strtab = cast(const(char)*)(info.dlpi_addr + dyn.d_un.d_ptr); // relocate
                 else version (NetBSD)
                     strtab = cast(const(char)*)(info.dlpi_addr + dyn.d_un.d_ptr); // relocate
+                else version (OpenBSD)
+                    strtab = cast(const(char)*)(info.dlpi_addr + dyn.d_un.d_ptr); // relocate
                 else version (DragonFlyBSD)
                     strtab = cast(const(char)*)(info.dlpi_addr + dyn.d_un.d_ptr); // relocate
                 else version (Solaris)
@@ -821,9 +806,21 @@ version (Shared)
 
     void* handleForName(const char* name)
     {
-        auto handle = .dlopen(name, RTLD_NOLOAD | RTLD_LAZY);
-        version (Solaris) { }
-        else if (handle !is null) .dlclose(handle); // drop reference count
+        version (Solaris) enum refCounted = false;
+        else version (OpenBSD) enum refCounted = false;
+        else enum refCounted = true;
+
+        static if (__traits(compiles, RTLD_NOLOAD))
+            enum flags = (RTLD_NOLOAD | RTLD_LAZY);
+        else
+            enum flags = RTLD_LAZY;
+
+        auto handle = .dlopen(name, flags);
+        static if (refCounted)
+        {
+            if (handle !is null)
+                .dlclose(handle); // drop reference count
+        }
         return handle;
     }
 }
@@ -917,6 +914,7 @@ bool findDSOInfoForAddr(in void* addr, dl_phdr_info* result=null) nothrow @nogc
 {
     version (linux)        enum IterateManually = true;
     else version (NetBSD)  enum IterateManually = true;
+    else version (OpenBSD) enum IterateManually = true;
     else version (Solaris) enum IterateManually = true;
     else                   enum IterateManually = false;
 
@@ -976,29 +974,6 @@ bool findSegmentForAddr(in ref dl_phdr_info info, in void* addr, ElfW!"Phdr"* re
     return false;
 }
 
-version (linux) import core.sys.linux.errno : program_invocation_name;
-// should be in core.sys.freebsd.stdlib
-version (FreeBSD) extern(C) const(char)* getprogname() nothrow @nogc;
-version (DragonFlyBSD) extern(C) const(char)* getprogname() nothrow @nogc;
-version (NetBSD) extern(C) const(char)* getprogname() nothrow @nogc;
-version (Solaris) extern(C) const(char)* getprogname() nothrow @nogc;
-
-@property const(char)* progname() nothrow @nogc
-{
-    version (linux) return program_invocation_name;
-    version (FreeBSD) return getprogname();
-    version (DragonFlyBSD) return getprogname();
-    version (NetBSD) return getprogname();
-    version (Solaris) return getprogname();
-}
-
-const(char)[] dsoName(const char* dlpi_name) nothrow @nogc
-{
-    // the main executable doesn't have a name in its dlpi_name field
-    const char* p = dlpi_name[0] != 0 ? dlpi_name : progname;
-    return p[0 .. strlen(p)];
-}
-
 /**************************
  * Input:
  *      addr  an internal address of a DSO
diff --git a/libphobos/libdruntime/gcc/sections/macho.d b/libphobos/libdruntime/gcc/sections/macho.d
new file mode 100644
index 0000000..3ce58a5
--- /dev/null
+++ b/libphobos/libdruntime/gcc/sections/macho.d
@@ -0,0 +1,738 @@
+// MACHO-specific support for sections.
+// Copyright (C) 2021 Free Software Foundation, Inc.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+module gcc.sections.macho;
+
+version (OSX):
+
+import core.memory;
+import core.stdc.stdlib;
+import core.sys.darwin.dlfcn;
+import core.sys.darwin.mach.dyld;
+import core.sys.darwin.mach.getsect;
+import core.sys.posix.pthread;
+import rt.minfo;
+import rt.util.container.array;
+import rt.util.container.hashtab;
+import gcc.sections.common;
+
+version (GNU_EMUTLS)
+    import gcc.emutls;
+
+alias DSO SectionGroup;
+struct DSO
+{
+    static int opApply(scope int delegate(ref DSO) dg)
+    {
+        foreach (dso; _loadedDSOs)
+        {
+            if (auto res = dg(*dso))
+                return res;
+        }
+        return 0;
+    }
+
+    static int opApplyReverse(scope int delegate(ref DSO) dg)
+    {
+        foreach_reverse (dso; _loadedDSOs)
+        {
+            if (auto res = dg(*dso))
+                return res;
+        }
+        return 0;
+    }
+
+    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
+    {
+        return _moduleGroup.modules;
+    }
+
+    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
+    {
+        return _moduleGroup;
+    }
+
+    @property inout(void[])[] gcRanges() inout nothrow @nogc
+    {
+        return _gcRanges[];
+    }
+
+private:
+
+    invariant()
+    {
+        safeAssert(_moduleGroup.modules.length > 0, "No modules for DSO.");
+    }
+
+    void** _slot;
+    ModuleGroup _moduleGroup;
+    Array!(void[]) _gcRanges;
+
+    version (Shared)
+    {
+        Array!(void[]) _codeSegments; // array of code segments
+        Array!(DSO*) _deps; // D libraries needed by this DSO
+        void* _handle; // corresponding handle
+    }
+}
+
+/****
+ * Boolean flag set to true while the runtime is initialized.
+ */
+__gshared bool _isRuntimeInitialized;
+
+/****
+ * Gets called on program startup just before GC is initialized.
+ */
+void initSections() nothrow @nogc
+{
+    _isRuntimeInitialized = true;
+}
+
+/***
+ * Gets called on program shutdown just after GC is terminated.
+ */
+void finiSections() nothrow @nogc
+{
+    _isRuntimeInitialized = false;
+}
+
+alias ScanDG = void delegate(void* pbeg, void* pend) nothrow;
+
+version (Shared)
+{
+    import gcc.sections : pinLoadedLibraries, unpinLoadedLibraries,
+           inheritLoadedLibraries, cleanupLoadedLibraries;
+
+    /***
+     * Called once per thread; returns array of thread local storage ranges
+     */
+    Array!(ThreadDSO)* initTLSRanges() @nogc nothrow
+    {
+        return &_loadedDSOs();
+    }
+
+    void finiTLSRanges(Array!(ThreadDSO)* tdsos) @nogc nothrow
+    {
+        // Nothing to do here. tdsos used to point to the _loadedDSOs instance
+        // in the dying thread's TLS segment and as such is not valid anymore.
+        // The memory for the array contents was already reclaimed in
+        // cleanupLoadedLibraries().
+    }
+
+    void scanTLSRanges(Array!(ThreadDSO)* tdsos, scope ScanDG dg) nothrow
+    {
+        version (GNU_EMUTLS)
+            _d_emutls_scan(dg);
+        else
+            static assert(0, "Native TLS unimplemented");
+    }
+
+    // interface for core.thread to inherit loaded libraries
+    pragma(mangle, gcc.sections.pinLoadedLibraries.mangleof)
+    void* pinLoadedLibraries() nothrow @nogc
+    {
+        auto res = cast(Array!(ThreadDSO)*)calloc(1, Array!(ThreadDSO).sizeof);
+        res.length = _loadedDSOs.length;
+        foreach (i, ref tdso; _loadedDSOs)
+        {
+            (*res)[i] = tdso;
+            if (tdso._addCnt)
+            {
+                // Increment the dlopen ref for explicitly loaded libraries to pin them.
+                const success = .dlopen(nameForDSO(tdso._pdso), RTLD_LAZY) !is null;
+                safeAssert(success, "Failed to increment dlopen ref.");
+                (*res)[i]._addCnt = 1; // new array takes over the additional ref count
+            }
+        }
+        return res;
+    }
+
+    pragma(mangle, gcc.sections.unpinLoadedLibraries.mangleof)
+    void unpinLoadedLibraries(void* p) nothrow @nogc
+    {
+        auto pary = cast(Array!(ThreadDSO)*)p;
+        // In case something failed we need to undo the pinning.
+        foreach (ref tdso; *pary)
+        {
+            if (tdso._addCnt)
+            {
+                auto handle = tdso._pdso._handle;
+                safeAssert(handle !is null, "Invalid library handle.");
+                .dlclose(handle);
+            }
+        }
+        pary.reset();
+        .free(pary);
+    }
+
+    // Called before TLS ctors are ran, copy over the loaded libraries
+    // of the parent thread.
+    pragma(mangle, gcc.sections.inheritLoadedLibraries.mangleof)
+    void inheritLoadedLibraries(void* p) nothrow @nogc
+    {
+        safeAssert(_loadedDSOs.empty, "DSOs have already been registered for this thread.");
+        _loadedDSOs.swap(*cast(Array!(ThreadDSO)*)p);
+        .free(p);
+    }
+
+    // Called after all TLS dtors ran, decrements all remaining dlopen refs.
+    pragma(mangle, gcc.sections.cleanupLoadedLibraries.mangleof)
+    void cleanupLoadedLibraries() nothrow @nogc
+    {
+        foreach (ref tdso; _loadedDSOs)
+        {
+            if (tdso._addCnt == 0) continue;
+
+            auto handle = tdso._pdso._handle;
+            safeAssert(handle !is null, "Invalid DSO handle.");
+            for (; tdso._addCnt > 0; --tdso._addCnt)
+                .dlclose(handle);
+        }
+
+        // Free the memory for the array contents.
+        _loadedDSOs.reset();
+    }
+}
+else
+{
+    /***
+     * Called once per thread; returns array of thread local storage ranges
+     */
+    Array!(void[])* initTLSRanges() nothrow @nogc
+    {
+        return null;
+    }
+
+    void finiTLSRanges(Array!(void[])* rngs) nothrow @nogc
+    {
+    }
+
+    void scanTLSRanges(Array!(void[])* rngs, scope ScanDG dg) nothrow
+    {
+        version (GNU_EMUTLS)
+            _d_emutls_scan(dg);
+        else
+            static assert(0, "Native TLS unimplemented");
+    }
+}
+
+private:
+
+version (Shared)
+{
+    /*
+     * Array of thread local DSO metadata for all libraries loaded and
+     * initialized in this thread.
+     *
+     * Note:
+     *     A newly spawned thread will inherit these libraries.
+     * Note:
+     *     We use an array here to preserve the order of
+     *     initialization.  If that became a performance issue, we
+     *     could use a hash table and enumerate the DSOs during
+     *     loading so that the hash table values could be sorted when
+     *     necessary.
+     */
+    struct ThreadDSO
+    {
+        DSO* _pdso;
+        static if (_pdso.sizeof == 8) uint _refCnt, _addCnt;
+        else static if (_pdso.sizeof == 4) ushort _refCnt, _addCnt;
+        else static assert(0, "unimplemented");
+        alias _pdso this;
+    }
+
+    @property ref Array!(ThreadDSO) _loadedDSOs() @nogc nothrow
+    {
+        static Array!(ThreadDSO) x;
+        return x;
+    }
+
+    /*
+     * Set to true during rt_loadLibrary/rt_unloadLibrary calls.
+     */
+    bool _rtLoading;
+
+    /*
+     * Hash table to map the native handle (as returned by dlopen)
+     * to the corresponding DSO*, protected by a mutex.
+     */
+    __gshared pthread_mutex_t _handleToDSOMutex;
+    @property ref HashTab!(void*, DSO*) _handleToDSO() @nogc nothrow
+    {
+        __gshared HashTab!(void*, DSO*) x;
+        return x;
+    }
+}
+else
+{
+    /*
+     * Static DSOs loaded by the runtime linker. This includes the
+     * executable. These can't be unloaded.
+     */
+    @property ref Array!(DSO*) _loadedDSOs() @nogc nothrow
+    {
+        __gshared Array!(DSO*) x;
+        return x;
+    }
+
+    enum _rtLoading = false;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Compiler to runtime interface.
+///////////////////////////////////////////////////////////////////////////////
+
+struct MachHeader
+{
+    const(mach_header)* header; // the mach header of the image
+    intptr_t slide;             // virtural memory address slide amount
+}
+
+/****
+ * This data structure is generated by the compiler, and then passed to
+ * _d_dso_registry().
+ */
+struct CompilerDSOData
+{
+    size_t _version;                                       // currently 1
+    void** _slot;                                          // can be used to store runtime data
+    immutable(object.ModuleInfo*)* _minfo_beg, _minfo_end; // array of modules in this object file
+}
+
+T[] toRange(T)(T* beg, T* end) { return beg[0 .. end - beg]; }
+
+/* For each shared library and executable, the compiler generates code that
+ * sets up CompilerDSOData and calls _d_dso_registry().
+ * A pointer to that code is inserted into both the .ctors and .dtors
+ * segment so it gets called by the loader on startup and shutdown.
+ */
+extern(C) void _d_dso_registry(CompilerDSOData* data)
+{
+    // only one supported currently
+    safeAssert(data._version >= 1, "Incompatible compiler-generated DSO data version.");
+
+    // no backlink => register
+    if (*data._slot is null)
+    {
+        immutable firstDSO = _loadedDSOs.empty;
+        if (firstDSO) initLocks();
+
+        DSO* pdso = cast(DSO*).calloc(1, DSO.sizeof);
+        assert(typeid(DSO).initializer().ptr is null);
+        pdso._slot = data._slot;
+        *data._slot = pdso; // store backlink in library record
+
+        pdso._moduleGroup = ModuleGroup(toRange(data._minfo_beg, data._minfo_end));
+
+        MachHeader header = void;
+        const headerFound = findImageHeaderForAddr(data._slot, header);
+        safeAssert(headerFound, "Failed to find image header.");
+
+        scanSegments(header, pdso);
+
+        version (Shared)
+        {
+            auto handle = handleForAddr(data._slot);
+
+            getDependencies(header, pdso._deps);
+            pdso._handle = handle;
+            setDSOForHandle(pdso, pdso._handle);
+
+            if (!_rtLoading)
+            {
+                /* This DSO was not loaded by rt_loadLibrary which
+                 * happens for all dependencies of an executable or
+                 * the first dlopen call from a C program.
+                 * In this case we add the DSO to the _loadedDSOs of this
+                 * thread with a refCnt of 1 and call the TlsCtors.
+                 */
+                immutable ushort refCnt = 1, addCnt = 0;
+                _loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt));
+            }
+        }
+        else
+        {
+            foreach (p; _loadedDSOs)
+                safeAssert(p !is pdso, "DSO already registered.");
+            _loadedDSOs.insertBack(pdso);
+        }
+
+        // don't initialize modules before rt_init was called
+        if (_isRuntimeInitialized)
+        {
+            registerGCRanges(pdso);
+            // rt_loadLibrary will run tls ctors, so do this only for dlopen
+            immutable runTlsCtors = !_rtLoading;
+            runModuleConstructors(pdso, runTlsCtors);
+        }
+    }
+    // has backlink => unregister
+    else
+    {
+        DSO* pdso = cast(DSO*)*data._slot;
+        *data._slot = null;
+
+        // don't finalizes modules after rt_term was called (see Bugzilla 11378)
+        if (_isRuntimeInitialized)
+        {
+            // rt_unloadLibrary already ran tls dtors, so do this only for dlclose
+            immutable runTlsDtors = !_rtLoading;
+            runModuleDestructors(pdso, runTlsDtors);
+            unregisterGCRanges(pdso);
+            // run finalizers after module dtors (same order as in rt_term)
+            version (Shared) runFinalizers(pdso);
+        }
+
+        version (Shared)
+        {
+            if (!_rtLoading)
+            {
+                /* This DSO was not unloaded by rt_unloadLibrary so we
+                 * have to remove it from _loadedDSOs here.
+                 */
+                foreach (i, ref tdso; _loadedDSOs)
+                {
+                    if (tdso._pdso == pdso)
+                    {
+                        _loadedDSOs.remove(i);
+                        break;
+                    }
+                }
+            }
+
+            unsetDSOForHandle(pdso, pdso._handle);
+        }
+        else
+        {
+            // static DSOs are unloaded in reverse order
+            safeAssert(pdso == _loadedDSOs.back, "DSO being unregistered isn't current last one.");
+            _loadedDSOs.popBack();
+        }
+
+        freeDSO(pdso);
+
+        // last DSO being unloaded => shutdown registry
+        if (_loadedDSOs.empty)
+        {
+            version (GNU_EMUTLS)
+                _d_emutls_destroy();
+            version (Shared)
+            {
+                safeAssert(_handleToDSO.empty, "_handleToDSO not in sync with _loadedDSOs.");
+                _handleToDSO.reset();
+            }
+            finiLocks();
+        }
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// dynamic loading
+///////////////////////////////////////////////////////////////////////////////
+
+// Shared D libraries are only supported when linking against a shared druntime library.
+
+version (Shared)
+{
+    ThreadDSO* findThreadDSO(DSO* pdso) nothrow @nogc
+    {
+        foreach (ref tdata; _loadedDSOs)
+            if (tdata._pdso == pdso) return &tdata;
+        return null;
+    }
+
+    void incThreadRef(DSO* pdso, bool incAdd)
+    {
+        if (auto tdata = findThreadDSO(pdso)) // already initialized
+        {
+            if (incAdd && ++tdata._addCnt > 1) return;
+            ++tdata._refCnt;
+        }
+        else
+        {
+            foreach (dep; pdso._deps)
+                incThreadRef(dep, false);
+            immutable ushort refCnt = 1, addCnt = incAdd ? 1 : 0;
+            _loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt));
+            pdso._moduleGroup.runTlsCtors();
+        }
+    }
+
+    void decThreadRef(DSO* pdso, bool decAdd)
+    {
+        auto tdata = findThreadDSO(pdso);
+        safeAssert(tdata !is null, "Failed to find thread DSO.");
+        safeAssert(!decAdd || tdata._addCnt > 0, "Mismatching rt_unloadLibrary call.");
+
+        if (decAdd && --tdata._addCnt > 0) return;
+        if (--tdata._refCnt > 0) return;
+
+        pdso._moduleGroup.runTlsDtors();
+        foreach (i, ref td; _loadedDSOs)
+            if (td._pdso == pdso) _loadedDSOs.remove(i);
+        foreach (dep; pdso._deps)
+            decThreadRef(dep, false);
+    }
+
+    extern(C) void* rt_loadLibrary(const char* name)
+    {
+        immutable save = _rtLoading;
+        _rtLoading = true;
+        scope (exit) _rtLoading = save;
+
+        auto handle = .dlopen(name, RTLD_LAZY);
+        if (handle is null) return null;
+
+        // if it's a D library
+        if (auto pdso = dsoForHandle(handle))
+            incThreadRef(pdso, true);
+        return handle;
+    }
+
+    extern(C) int rt_unloadLibrary(void* handle)
+    {
+        if (handle is null) return false;
+
+        immutable save = _rtLoading;
+        _rtLoading = true;
+        scope (exit) _rtLoading = save;
+
+        // if it's a D library
+        if (auto pdso = dsoForHandle(handle))
+            decThreadRef(pdso, true);
+        return .dlclose(handle) == 0;
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// helper functions
+///////////////////////////////////////////////////////////////////////////////
+
+void initLocks() nothrow @nogc
+{
+    version (Shared)
+        !pthread_mutex_init(&_handleToDSOMutex, null) || assert(0);
+}
+
+void finiLocks() nothrow @nogc
+{
+    version (Shared)
+        !pthread_mutex_destroy(&_handleToDSOMutex) || assert(0);
+}
+
+void runModuleConstructors(DSO* pdso, bool runTlsCtors)
+{
+    pdso._moduleGroup.sortCtors();
+    pdso._moduleGroup.runCtors();
+    if (runTlsCtors) pdso._moduleGroup.runTlsCtors();
+}
+
+void runModuleDestructors(DSO* pdso, bool runTlsDtors)
+{
+    if (runTlsDtors) pdso._moduleGroup.runTlsDtors();
+    pdso._moduleGroup.runDtors();
+}
+
+void registerGCRanges(DSO* pdso) nothrow @nogc
+{
+    foreach (rng; pdso._gcRanges)
+        GC.addRange(rng.ptr, rng.length);
+}
+
+void unregisterGCRanges(DSO* pdso) nothrow @nogc
+{
+    foreach (rng; pdso._gcRanges)
+        GC.removeRange(rng.ptr);
+}
+
+version (Shared) void runFinalizers(DSO* pdso)
+{
+    foreach (seg; pdso._codeSegments)
+        GC.runFinalizers(seg);
+}
+
+void freeDSO(DSO* pdso) nothrow @nogc
+{
+    pdso._gcRanges.reset();
+    version (Shared)
+    {
+        pdso._codeSegments.reset();
+        pdso._deps.reset();
+        pdso._handle = null;
+    }
+    .free(pdso);
+}
+
+version (Shared)
+{
+@nogc nothrow:
+    const(char)* nameForDSO(in DSO* pdso)
+    {
+        Dl_info info = void;
+        const success = dladdr(pdso._slot, &info) != 0;
+        safeAssert(success, "Failed to get DSO info.");
+        return info.dli_fname;
+    }
+
+    DSO* dsoForHandle(void* handle)
+    {
+        DSO* pdso;
+        !pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
+        if (auto ppdso = handle in _handleToDSO)
+            pdso = *ppdso;
+        !pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
+        return pdso;
+    }
+
+    void setDSOForHandle(DSO* pdso, void* handle)
+    {
+        !pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
+        safeAssert(handle !in _handleToDSO, "DSO already registered.");
+        _handleToDSO[handle] = pdso;
+        !pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
+    }
+
+    void unsetDSOForHandle(DSO* pdso, void* handle)
+    {
+        !pthread_mutex_lock(&_handleToDSOMutex) || assert(0);
+        safeAssert(_handleToDSO[handle] == pdso, "Handle doesn't match registered DSO.");
+        _handleToDSO.remove(handle);
+        !pthread_mutex_unlock(&_handleToDSOMutex) || assert(0);
+    }
+
+    void getDependencies(in MachHeader info, ref Array!(DSO*) deps)
+    {
+        // FIXME: Not implemented yet.
+    }
+
+    void* handleForName(const char* name)
+    {
+        auto handle = .dlopen(name, RTLD_NOLOAD | RTLD_LAZY);
+        if (handle !is null) .dlclose(handle); // drop reference count
+        return handle;
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Mach-O program header iteration
+///////////////////////////////////////////////////////////////////////////////
+
+/************
+ * Scan segments in the image header and store
+ * the writeable data segments in *pdso.
+ */
+
+void scanSegments(in MachHeader info, DSO* pdso)
+{
+    foreach (e; dataSegs)
+    {
+        auto sect = getSection(info.header, info.slide, e.seg.ptr, e.sect.ptr);
+        if (sect != null)
+            pdso._gcRanges.insertBack((cast(void*)sect.ptr)[0 .. sect.length]);
+    }
+
+    version (Shared)
+    {
+        void[] text = getSection(info.header, info.slide, "__TEXT", "__text");
+        if (!text)
+            assert(0, "Failed to get text section.");
+        pdso._codeSegments.insertBack(text);
+    }
+}
+
+/**************************
+ * Input:
+ *      result where the output is to be written
+ * Returns:
+ *      true if found, and *result is filled in
+ */
+
+bool findImageHeaderForAddr(in void* addr, out MachHeader result)
+{
+    Dl_info info;
+    if (dladdr(addr, &info) == 0)
+        return false;
+
+    foreach (i; 0 .. _dyld_image_count())
+    {
+        if (info.dli_fbase == _dyld_get_image_header(i))
+        {
+            result.header = cast(const(mach_header)*)info.dli_fbase;
+            result.slide = _dyld_get_image_vmaddr_slide(i);
+            return true;
+        }
+    }
+    return false;
+}
+
+/**************************
+ * Input:
+ *      addr  an internal address of a DSO
+ * Returns:
+ *      the dlopen handle for that DSO or null if addr is not within a loaded DSO
+ */
+version (Shared) void* handleForAddr(void* addr) nothrow @nogc
+{
+    Dl_info info = void;
+    if (dladdr(addr, &info) != 0)
+        return handleForName(info.dli_fname);
+    return null;
+}
+
+struct SegRef
+{
+    string seg;
+    string sect;
+}
+
+static immutable SegRef[] dataSegs = [{SEG_DATA, SECT_DATA},
+                                      {SEG_DATA, SECT_BSS},
+                                      {SEG_DATA, SECT_COMMON}];
+
+/**
+ * Returns the section for the named section in the named segment
+ * for the mach_header pointer passed, or null if not found.
+ */
+ubyte[] getSection(in mach_header* header, intptr_t slide,
+                   in char* segmentName, in char* sectionName)
+{
+    version (D_LP64)
+    {
+        assert(header.magic == MH_MAGIC_64);
+        auto sect = getsectbynamefromheader_64(cast(mach_header_64*)header,
+                                            segmentName,
+                                            sectionName);
+    }
+    else
+    {
+        assert(header.magic == MH_MAGIC);
+        auto sect = getsectbynamefromheader(header,
+                                            segmentName,
+                                            sectionName);
+    }
+
+    if (sect !is null && sect.size > 0)
+        return (cast(ubyte*)sect.addr + slide)[0 .. cast(size_t)sect.size];
+    return null;
+}
diff --git a/libphobos/libdruntime/gcc/sections/osx.d b/libphobos/libdruntime/gcc/sections/osx.d
deleted file mode 100644
index 3e3db70..0000000
--- a/libphobos/libdruntime/gcc/sections/osx.d
+++ /dev/null
@@ -1,284 +0,0 @@
-// OSX-specific support for sections.
-// Copyright (C) 2019-2021 Free Software Foundation, Inc.
-
-// GCC is free software; you can redistribute it and/or modify it under
-// the terms of the GNU General Public License as published by the Free
-// Software Foundation; either version 3, or (at your option) any later
-// version.
-
-// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
-// WARRANTY; without even the implied warranty of MERCHANTABILITY or
-// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-// for more details.
-
-// Under Section 7 of GPL version 3, you are granted additional
-// permissions described in the GCC Runtime Library Exception, version
-// 3.1, as published by the Free Software Foundation.
-
-// You should have received a copy of the GNU General Public License and
-// a copy of the GCC Runtime Library Exception along with this program;
-// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
-// <http://www.gnu.org/licenses/>.
-
-module gcc.sections.osx;
-
-version (OSX):
-
-// debug = PRINTF;
-import core.stdc.stdio;
-import core.stdc.string, core.stdc.stdlib;
-import core.sys.posix.pthread;
-import core.sys.darwin.mach.dyld;
-import core.sys.darwin.mach.getsect;
-import rt.deh, rt.minfo;
-import rt.util.container.array;
-
-struct SectionGroup
-{
-    static int opApply(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    static int opApplyReverse(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
-    {
-        return _moduleGroup.modules;
-    }
-
-    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
-    {
-        return _moduleGroup;
-    }
-
-    @property inout(void[])[] gcRanges() inout nothrow @nogc
-    {
-        return _gcRanges[];
-    }
-
-    @property immutable(FuncTable)[] ehTables() const nothrow @nogc
-    {
-        return _ehTables[];
-    }
-
-private:
-    immutable(FuncTable)[] _ehTables;
-    ModuleGroup _moduleGroup;
-    Array!(void[]) _gcRanges;
-    immutable(void)[][2] _tlsImage;
-}
-
-/****
- * Boolean flag set to true while the runtime is initialized.
- */
-__gshared bool _isRuntimeInitialized;
-
-/****
- * Gets called on program startup just before GC is initialized.
- */
-void initSections() nothrow @nogc
-{
-    pthread_key_create(&_tlsKey, null);
-    _dyld_register_func_for_add_image(&sections_osx_onAddImage);
-    _isRuntimeInitialized = true;
-}
-
-/***
- * Gets called on program shutdown just after GC is terminated.
- */
-void finiSections() nothrow @nogc
-{
-    _sections._gcRanges.reset();
-    pthread_key_delete(_tlsKey);
-    _isRuntimeInitialized = false;
-}
-
-void[]* initTLSRanges() nothrow @nogc
-{
-    return &getTLSBlock();
-}
-
-void finiTLSRanges(void[]* rng) nothrow @nogc
-{
-    .free(rng.ptr);
-    .free(rng);
-}
-
-void scanTLSRanges(void[]* rng, scope void delegate(void* pbeg, void* pend) nothrow dg) nothrow
-{
-    dg(rng.ptr, rng.ptr + rng.length);
-}
-
-// NOTE: The Mach-O object file format does not allow for thread local
-//       storage declarations. So instead we roll our own by putting tls
-//       into the __tls_data and the __tlscoal_nt sections.
-//
-//       This function is called by the code emitted by the compiler.  It
-//       is expected to translate an address into the TLS static data to
-//       the corresponding address in the TLS dynamic per-thread data.
-
-// NB: the compiler mangles this function as '___tls_get_addr' even though it is extern(D)
-extern(D) void* ___tls_get_addr( void* p )
-{
-    immutable off = tlsOffset(p);
-    auto tls = getTLSBlockAlloc();
-    assert(off < tls.length);
-    return tls.ptr + off;
-}
-
-private:
-
-__gshared pthread_key_t _tlsKey;
-
-size_t tlsOffset(void* p)
-in
-{
-    assert(_sections._tlsImage[0].ptr !is null ||
-           _sections._tlsImage[1].ptr !is null);
-}
-body
-{
-    // NOTE: p is an address in the TLS static data emitted by the
-    //       compiler.  If it isn't, something is disastrously wrong.
-    immutable off0 = cast(size_t)(p - _sections._tlsImage[0].ptr);
-    if (off0 < _sections._tlsImage[0].length)
-    {
-        return off0;
-    }
-    immutable off1 = cast(size_t)(p - _sections._tlsImage[1].ptr);
-    if (off1 < _sections._tlsImage[1].length)
-    {
-        size_t sz = (_sections._tlsImage[0].length + 15) & ~cast(size_t)15;
-        return sz + off1;
-    }
-    assert(0);
-}
-
-ref void[] getTLSBlock() nothrow @nogc
-{
-    auto pary = cast(void[]*)pthread_getspecific(_tlsKey);
-    if (pary is null)
-    {
-        pary = cast(void[]*).calloc(1, (void[]).sizeof);
-        if (pthread_setspecific(_tlsKey, pary) != 0)
-        {
-            import core.stdc.stdio;
-            perror("pthread_setspecific failed with");
-            assert(0);
-        }
-    }
-    return *pary;
-}
-
-ref void[] getTLSBlockAlloc()
-{
-    auto pary = &getTLSBlock();
-    if (!pary.length)
-    {
-        auto imgs = _sections._tlsImage;
-        immutable sz0 = (imgs[0].length + 15) & ~cast(size_t)15;
-        immutable sz2 = sz0 + imgs[1].length;
-        auto p = .malloc(sz2);
-        memcpy(p, imgs[0].ptr, imgs[0].length);
-        memcpy(p + sz0, imgs[1].ptr, imgs[1].length);
-        *pary = p[0 .. sz2];
-    }
-    return *pary;
-}
-
-__gshared SectionGroup _sections;
-
-extern (C) void sections_osx_onAddImage(in mach_header* h, intptr_t slide)
-{
-    foreach (e; dataSegs)
-    {
-        auto sect = getSection(h, slide, e.seg.ptr, e.sect.ptr);
-        if (sect != null)
-            _sections._gcRanges.insertBack((cast(void*)sect.ptr)[0 .. sect.length]);
-    }
-
-    auto minfosect = getSection(h, slide, "__DATA", "__minfodata");
-    if (minfosect != null)
-    {
-        // no support for multiple images yet
-        // take the sections from the last static image which is the executable
-        if (_isRuntimeInitialized)
-        {
-            fprintf(stderr, "Loading shared libraries isn't yet supported on OSX.\n");
-            return;
-        }
-        else if (_sections.modules.ptr !is null)
-        {
-            fprintf(stderr, "Shared libraries are not yet supported on OSX.\n");
-        }
-
-        debug(PRINTF) printf("  minfodata\n");
-        auto p = cast(immutable(ModuleInfo*)*)minfosect.ptr;
-        immutable len = minfosect.length / (*p).sizeof;
-
-        _sections._moduleGroup = ModuleGroup(p[0 .. len]);
-    }
-
-    auto ehsect = getSection(h, slide, "__DATA", "__deh_eh");
-    if (ehsect != null)
-    {
-        debug(PRINTF) printf("  deh_eh\n");
-        auto p = cast(immutable(FuncTable)*)ehsect.ptr;
-        immutable len = ehsect.length / (*p).sizeof;
-
-        _sections._ehTables = p[0 .. len];
-    }
-
-    auto tlssect = getSection(h, slide, "__DATA", "__tls_data");
-    if (tlssect != null)
-    {
-        debug(PRINTF) printf("  tls_data %p %p\n", tlssect.ptr, tlssect.ptr + tlssect.length);
-        _sections._tlsImage[0] = (cast(immutable(void)*)tlssect.ptr)[0 .. tlssect.length];
-    }
-
-    auto tlssect2 = getSection(h, slide, "__DATA", "__tlscoal_nt");
-    if (tlssect2 != null)
-    {
-        debug(PRINTF) printf("  tlscoal_nt %p %p\n", tlssect2.ptr, tlssect2.ptr + tlssect2.length);
-        _sections._tlsImage[1] = (cast(immutable(void)*)tlssect2.ptr)[0 .. tlssect2.length];
-    }
-}
-
-struct SegRef
-{
-    string seg;
-    string sect;
-}
-
-static immutable SegRef[] dataSegs = [{SEG_DATA, SECT_DATA},
-                                      {SEG_DATA, SECT_BSS},
-                                      {SEG_DATA, SECT_COMMON}];
-
-ubyte[] getSection(in mach_header* header, intptr_t slide,
-                   in char* segmentName, in char* sectionName)
-{
-    version (X86)
-    {
-        assert(header.magic == MH_MAGIC);
-        auto sect = getsectbynamefromheader(header,
-                                            segmentName,
-                                            sectionName);
-    }
-    else version (X86_64)
-    {
-        assert(header.magic == MH_MAGIC_64);
-        auto sect = getsectbynamefromheader_64(cast(mach_header_64*)header,
-                                            segmentName,
-                                            sectionName);
-    }
-    else
-        static assert(0, "unimplemented");
-
-    if (sect !is null && sect.size > 0)
-        return (cast(ubyte*)sect.addr + slide)[0 .. cast(size_t)sect.size];
-    return null;
-}
diff --git a/libphobos/libdruntime/gcc/sections/package.d b/libphobos/libdruntime/gcc/sections/package.d
index fdaf039..1e887cd 100644
--- a/libphobos/libdruntime/gcc/sections/package.d
+++ b/libphobos/libdruntime/gcc/sections/package.d
@@ -22,27 +22,31 @@
 
 module gcc.sections;
 
-version (CRuntime_Glibc)
-    public import gcc.sections.elf_shared;
-else version (CRuntime_Musl)
-    public import gcc.sections.elf_shared;
-else version (CRuntime_UClibc)
-    public import gcc.sections.elf_shared;
-else version (FreeBSD)
-    public import gcc.sections.elf_shared;
-else version (NetBSD)
-    public import gcc.sections.elf_shared;
-else version (DragonFlyBSD)
-    public import gcc.sections.elf_shared;
-else version (Solaris)
-    public import gcc.sections.elf_shared;
-else version (OSX)
-    public import gcc.sections.osx;
-else version (CRuntime_DigitalMars)
-    public import gcc.sections.win32;
-else version (CRuntime_Microsoft)
-    public import gcc.sections.win64;
-else version (CRuntime_Bionic)
-    public import gcc.sections.android;
+version (CRuntime_Glibc)  version = SectionsElf;
+version (CRuntime_Musl)   version = SectionsElf;
+version (CRuntime_UClibc) version = SectionsElf;
+version (FreeBSD)         version = SectionsElf;
+version (NetBSD)          version = SectionsElf;
+version (OpenBSD)         version = SectionsElf;
+version (DragonFlyBSD)    version = SectionsElf;
+version (Solaris)         version = SectionsElf;
+version (OSX)             version = SectionsMacho;
+version (Windows)         version = SectionsPeCoff;
+
+version (SectionsElf)
+    public import gcc.sections.elf;
+else version (SectionsMacho)
+    public import gcc.sections.macho;
+else version (SectionsPeCoff)
+    public import gcc.sections.pecoff;
 else
     static assert(0, "unimplemented");
+
+version (Shared)
+{
+    // interface for core.thread to inherit loaded libraries
+    void* pinLoadedLibraries() nothrow @nogc;
+    void unpinLoadedLibraries(void* p) nothrow @nogc;
+    void inheritLoadedLibraries(void* p) nothrow @nogc;
+    void cleanupLoadedLibraries() nothrow @nogc;
+}
diff --git a/libphobos/libdruntime/gcc/sections/pecoff.d b/libphobos/libdruntime/gcc/sections/pecoff.d
new file mode 100644
index 0000000..ed0340e
--- /dev/null
+++ b/libphobos/libdruntime/gcc/sections/pecoff.d
@@ -0,0 +1,826 @@
+// PE/COFF-specific support for sections.
+// Copyright (C) 2021 Free Software Foundation, Inc.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+// <http://www.gnu.org/licenses/>.
+
+module gcc.sections.pecoff;
+
+version (Windows):
+
+import core.memory;
+import core.stdc.stdlib;
+import core.sys.windows.winbase;
+import core.sys.windows.windef;
+import core.sys.windows.winnt;
+import rt.minfo;
+import rt.util.container.array;
+import rt.util.container.hashtab;
+import gcc.sections.common;
+
+version (GNU_EMUTLS)
+    import gcc.emutls;
+
+alias DSO SectionGroup;
+struct DSO
+{
+    static int opApply(scope int delegate(ref DSO) dg)
+    {
+        foreach (dso; _loadedDSOs)
+        {
+            if (auto res = dg(*dso))
+                return res;
+        }
+        return 0;
+    }
+
+    static int opApplyReverse(scope int delegate(ref DSO) dg)
+    {
+        foreach_reverse (dso; _loadedDSOs)
+        {
+            if (auto res = dg(*dso))
+                return res;
+        }
+        return 0;
+    }
+
+    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
+    {
+        return _moduleGroup.modules;
+    }
+
+    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
+    {
+        return _moduleGroup;
+    }
+
+    @property inout(void[])[] gcRanges() inout nothrow @nogc
+    {
+        return _gcRanges[];
+    }
+
+private:
+
+    invariant()
+    {
+        safeAssert(_moduleGroup.modules.length > 0, "No modules for DSO.");
+    }
+
+    void** _slot;
+    ModuleGroup _moduleGroup;
+    Array!(void[]) _gcRanges;
+
+    version (Shared)
+    {
+        Array!(void[]) _codeSegments; // array of code segments
+        Array!(DSO*) _deps; // D libraries needed by this DSO
+        void* _handle; // corresponding handle
+    }
+}
+
+/****
+ * Boolean flag set to true while the runtime is initialized.
+ */
+__gshared bool _isRuntimeInitialized;
+
+/****
+ * Gets called on program startup just before GC is initialized.
+ */
+void initSections() nothrow @nogc
+{
+    _isRuntimeInitialized = true;
+}
+
+/***
+ * Gets called on program shutdown just after GC is terminated.
+ */
+void finiSections() nothrow @nogc
+{
+    _isRuntimeInitialized = false;
+}
+
+alias ScanDG = void delegate(void* pbeg, void* pend) nothrow;
+
+version (Shared)
+{
+    import gcc.sections : pinLoadedLibraries, unpinLoadedLibraries,
+           inheritLoadedLibraries, cleanupLoadedLibraries;
+
+    /***
+     * Called once per thread; returns array of thread local storage ranges
+     */
+    Array!(ThreadDSO)* initTLSRanges() @nogc nothrow
+    {
+        return &_loadedDSOs();
+    }
+
+    void finiTLSRanges(Array!(ThreadDSO)* tdsos) @nogc nothrow
+    {
+        // Nothing to do here. tdsos used to point to the _loadedDSOs instance
+        // in the dying thread's TLS segment and as such is not valid anymore.
+        // The memory for the array contents was already reclaimed in
+        // cleanupLoadedLibraries().
+    }
+
+    void scanTLSRanges(Array!(ThreadDSO)* tdsos, scope ScanDG dg) nothrow
+    {
+        version (GNU_EMUTLS)
+            _d_emutls_scan(dg);
+        else
+            static assert(0, "Native TLS unimplemented");
+    }
+
+    // interface for core.thread to inherit loaded libraries
+    pragma(mangle, gcc.sections.pinLoadedLibraries.mangleof)
+    void* pinLoadedLibraries() nothrow @nogc
+    {
+        auto res = cast(Array!(ThreadDSO)*)calloc(1, Array!(ThreadDSO).sizeof);
+        res.length = _loadedDSOs.length;
+        foreach (i, ref tdso; _loadedDSOs)
+        {
+            (*res)[i] = tdso;
+            if (tdso._addCnt)
+            {
+                // Increment the DLL ref for explicitly loaded libraries to pin them.
+                char[MAX_PATH] buf;
+                char[] buffer = buf[];
+                const success = .LoadLibraryA(nameForDSO(tdso._pdso, buffer)) !is null;
+                safeAssert(success, "Failed to increment DLL ref.");
+                (*res)[i]._addCnt = 1; // new array takes over the additional ref count
+            }
+        }
+        return res;
+    }
+
+    pragma(mangle, gcc.sections.unpinLoadedLibraries.mangleof)
+    void unpinLoadedLibraries(void* p) nothrow @nogc
+    {
+        auto pary = cast(Array!(ThreadDSO)*)p;
+        // In case something failed we need to undo the pinning.
+        foreach (ref tdso; *pary)
+        {
+            if (tdso._addCnt)
+            {
+                auto handle = tdso._pdso._handle;
+                safeAssert(handle !is null, "Invalid library handle.");
+                .FreeLibrary(handle);
+            }
+        }
+        pary.reset();
+        .free(pary);
+    }
+
+    // Called before TLS ctors are ran, copy over the loaded libraries
+    // of the parent thread.
+    pragma(mangle, gcc.sections.inheritLoadedLibraries.mangleof)
+    void inheritLoadedLibraries(void* p) nothrow @nogc
+    {
+        safeAssert(_loadedDSOs.empty, "DSOs have already been registered for this thread.");
+        _loadedDSOs.swap(*cast(Array!(ThreadDSO)*)p);
+        .free(p);
+    }
+
+    // Called after all TLS dtors ran, decrements all remaining DLL refs.
+    pragma(mangle, gcc.sections.cleanupLoadedLibraries.mangleof)
+    void cleanupLoadedLibraries() nothrow @nogc
+    {
+        foreach (ref tdso; _loadedDSOs)
+        {
+            if (tdso._addCnt == 0) continue;
+
+            auto handle = tdso._pdso._handle;
+            safeAssert(handle !is null, "Invalid DSO handle.");
+            for (; tdso._addCnt > 0; --tdso._addCnt)
+                .FreeLibrary(handle);
+        }
+
+        // Free the memory for the array contents.
+        _loadedDSOs.reset();
+    }
+}
+else
+{
+    /***
+     * Called once per thread; returns array of thread local storage ranges
+     */
+    Array!(void[])* initTLSRanges() nothrow @nogc
+    {
+        return null;
+    }
+
+    void finiTLSRanges(Array!(void[])* rngs) nothrow @nogc
+    {
+    }
+
+    void scanTLSRanges(Array!(void[])* rngs, scope ScanDG dg) nothrow
+    {
+        version (GNU_EMUTLS)
+            _d_emutls_scan(dg);
+        else
+            static assert(0, "Native TLS unimplemented");
+    }
+}
+
+private:
+
+version (Shared)
+{
+    /*
+     * Array of thread local DSO metadata for all libraries loaded and
+     * initialized in this thread.
+     *
+     * Note:
+     *     A newly spawned thread will inherit these libraries.
+     * Note:
+     *     We use an array here to preserve the order of
+     *     initialization.  If that became a performance issue, we
+     *     could use a hash table and enumerate the DSOs during
+     *     loading so that the hash table values could be sorted when
+     *     necessary.
+     */
+    struct ThreadDSO
+    {
+        DSO* _pdso;
+        static if (_pdso.sizeof == 8) uint _refCnt, _addCnt;
+        else static if (_pdso.sizeof == 4) ushort _refCnt, _addCnt;
+        else static assert(0, "unimplemented");
+        alias _pdso this;
+    }
+
+    @property ref Array!(ThreadDSO) _loadedDSOs() @nogc nothrow
+    {
+        static Array!(ThreadDSO) x;
+        return x;
+    }
+
+    /*
+     * Set to true during rt_loadLibrary/rt_unloadLibrary calls.
+     */
+    bool _rtLoading;
+
+    /*
+     * Hash table to map the native handle (as returned by dlopen)
+     * to the corresponding DSO*, protected by a mutex.
+     */
+    __gshared CRITICAL_SECTION _handleToDSOMutex;
+    @property ref HashTab!(void*, DSO*) _handleToDSO() @nogc nothrow
+    {
+        __gshared HashTab!(void*, DSO*) x;
+        return x;
+    }
+}
+else
+{
+    /*
+     * Static DSOs loaded by the runtime linker. This includes the
+     * executable. These can't be unloaded.
+     */
+    @property ref Array!(DSO*) _loadedDSOs() @nogc nothrow
+    {
+        __gshared Array!(DSO*) x;
+        return x;
+    }
+
+    enum _rtLoading = false;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// Compiler to runtime interface.
+///////////////////////////////////////////////////////////////////////////////
+
+/****
+ * This data structure is generated by the compiler, and then passed to
+ * _d_dso_registry().
+ */
+struct CompilerDSOData
+{
+    size_t _version;                                       // currently 1
+    void** _slot;                                          // can be used to store runtime data
+    immutable(object.ModuleInfo*)* _minfo_beg, _minfo_end; // array of modules in this object file
+}
+
+T[] toRange(T)(T* beg, T* end) { return beg[0 .. end - beg]; }
+
+/* For each shared library and executable, the compiler generates code that
+ * sets up CompilerDSOData and calls _d_dso_registry().
+ * A pointer to that code is inserted into both the .ctors and .dtors
+ * segment so it gets called by the loader on startup and shutdown.
+ */
+extern(C) void _d_dso_registry(CompilerDSOData* data)
+{
+    // only one supported currently
+    safeAssert(data._version >= 1, "Incompatible compiler-generated DSO data version.");
+
+    // no backlink => register
+    if (*data._slot is null)
+    {
+        immutable firstDSO = _loadedDSOs.empty;
+        if (firstDSO) initLocks();
+
+        DSO* pdso = cast(DSO*).calloc(1, DSO.sizeof);
+        assert(typeid(DSO).initializer().ptr is null);
+        pdso._slot = data._slot;
+        *data._slot = pdso; // store backlink in library record
+
+        pdso._moduleGroup = ModuleGroup(toRange(data._minfo_beg, data._minfo_end));
+
+        HMODULE handle = void;
+        const moduleFound = findModuleHandleForAddr(data._slot, handle);
+        safeAssert(moduleFound, "Failed to find image header.");
+
+        scanSegments(handle, pdso);
+
+        version (Shared)
+        {
+            getDependencies(handle, pdso._deps);
+            pdso._handle = handle;
+            setDSOForHandle(pdso, pdso._handle);
+
+            if (!_rtLoading)
+            {
+                /* This DSO was not loaded by rt_loadLibrary which
+                 * happens for all dependencies of an executable or
+                 * the first dlopen call from a C program.
+                 * In this case we add the DSO to the _loadedDSOs of this
+                 * thread with a refCnt of 1 and call the TlsCtors.
+                 */
+                immutable ushort refCnt = 1, addCnt = 0;
+                _loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt));
+            }
+        }
+        else
+        {
+            foreach (p; _loadedDSOs)
+                safeAssert(p !is pdso, "DSO already registered.");
+            _loadedDSOs.insertBack(pdso);
+        }
+
+        // don't initialize modules before rt_init was called
+        if (_isRuntimeInitialized)
+        {
+            registerGCRanges(pdso);
+            // rt_loadLibrary will run tls ctors, so do this only for dlopen
+            immutable runTlsCtors = !_rtLoading;
+            runModuleConstructors(pdso, runTlsCtors);
+        }
+    }
+    // has backlink => unregister
+    else
+    {
+        DSO* pdso = cast(DSO*)*data._slot;
+        *data._slot = null;
+
+        // don't finalizes modules after rt_term was called (see Bugzilla 11378)
+        if (_isRuntimeInitialized)
+        {
+            // rt_unloadLibrary already ran tls dtors, so do this only for dlclose
+            immutable runTlsDtors = !_rtLoading;
+            runModuleDestructors(pdso, runTlsDtors);
+            unregisterGCRanges(pdso);
+            // run finalizers after module dtors (same order as in rt_term)
+            version (Shared) runFinalizers(pdso);
+        }
+
+        version (Shared)
+        {
+            if (!_rtLoading)
+            {
+                /* This DSO was not unloaded by rt_unloadLibrary so we
+                 * have to remove it from _loadedDSOs here.
+                 */
+                foreach (i, ref tdso; _loadedDSOs)
+                {
+                    if (tdso._pdso == pdso)
+                    {
+                        _loadedDSOs.remove(i);
+                        break;
+                    }
+                }
+            }
+
+            unsetDSOForHandle(pdso, pdso._handle);
+        }
+        else
+        {
+            // static DSOs are unloaded in reverse order
+            safeAssert(pdso == _loadedDSOs.back, "DSO being unregistered isn't current last one.");
+            _loadedDSOs.popBack();
+        }
+
+        freeDSO(pdso);
+
+        // last DSO being unloaded => shutdown registry
+        if (_loadedDSOs.empty)
+        {
+            version (GNU_EMUTLS)
+                _d_emutls_destroy();
+            version (Shared)
+            {
+                safeAssert(_handleToDSO.empty, "_handleToDSO not in sync with _loadedDSOs.");
+                _handleToDSO.reset();
+            }
+            finiLocks();
+        }
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// dynamic loading
+///////////////////////////////////////////////////////////////////////////////
+
+// Shared D libraries are only supported when linking against a shared druntime library.
+
+version (Shared)
+{
+    ThreadDSO* findThreadDSO(DSO* pdso) nothrow @nogc
+    {
+        foreach (ref tdata; _loadedDSOs)
+            if (tdata._pdso == pdso) return &tdata;
+        return null;
+    }
+
+    void incThreadRef(DSO* pdso, bool incAdd)
+    {
+        if (auto tdata = findThreadDSO(pdso)) // already initialized
+        {
+            if (incAdd && ++tdata._addCnt > 1) return;
+            ++tdata._refCnt;
+        }
+        else
+        {
+            foreach (dep; pdso._deps)
+                incThreadRef(dep, false);
+            immutable ushort refCnt = 1, addCnt = incAdd ? 1 : 0;
+            _loadedDSOs.insertBack(ThreadDSO(pdso, refCnt, addCnt));
+            pdso._moduleGroup.runTlsCtors();
+        }
+    }
+
+    void decThreadRef(DSO* pdso, bool decAdd)
+    {
+        auto tdata = findThreadDSO(pdso);
+        safeAssert(tdata !is null, "Failed to find thread DSO.");
+        safeAssert(!decAdd || tdata._addCnt > 0, "Mismatching rt_unloadLibrary call.");
+
+        if (decAdd && --tdata._addCnt > 0) return;
+        if (--tdata._refCnt > 0) return;
+
+        pdso._moduleGroup.runTlsDtors();
+        foreach (i, ref td; _loadedDSOs)
+            if (td._pdso == pdso) _loadedDSOs.remove(i);
+        foreach (dep; pdso._deps)
+            decThreadRef(dep, false);
+    }
+}
+
+/***********************************
+ * These are a temporary means of providing a GC hook for DLL use.  They may be
+ * replaced with some other similar functionality later.
+ */
+extern (C)
+{
+    void* gc_getProxy();
+    void  gc_setProxy(void* p);
+    void  gc_clrProxy();
+
+    alias void  function(void*) gcSetFn;
+    alias void  function()      gcClrFn;
+}
+
+/*******************************************
+ * Loads a DLL written in D with the name 'name'.
+ * Returns:
+ *      opaque handle to the DLL if successfully loaded
+ *      null if failure
+ */
+extern(C) void* rt_loadLibrary(const char* name)
+{
+    version (Shared)
+    {
+        immutable save = _rtLoading;
+        _rtLoading = true;
+        scope (exit) _rtLoading = save;
+    }
+    return initLibrary(.LoadLibraryA(name));
+}
+
+extern (C) void* rt_loadLibraryW(const wchar_t* name)
+{
+    version (Shared)
+    {
+        immutable save = _rtLoading;
+        _rtLoading = true;
+        scope (exit) _rtLoading = save;
+    }
+    return initLibrary(.LoadLibraryW(name));
+}
+
+void* initLibrary(void* handle)
+{
+    if (handle is null)
+        return null;
+
+    version (Shared)
+    {
+        // if it's a D library
+        if (auto pdso = dsoForHandle(handle))
+            incThreadRef(pdso, true);
+    }
+    gcSetFn gcSet = cast(gcSetFn) GetProcAddress(handle, "gc_setProxy");
+    if (gcSet !is null)
+    {
+        // BUG: Set proxy, but too late
+        gcSet(gc_getProxy());
+    }
+    return handle;
+}
+
+/*************************************
+ * Unloads DLL that was previously loaded by rt_loadLibrary().
+ * Input:
+ *      handle  the handle returned by rt_loadLibrary()
+ * Returns:
+ *      1   succeeded
+ *      0   some failure happened
+ */
+extern(C) int rt_unloadLibrary(void* handle)
+{
+    if (handle is null)
+        return false;
+
+    version (Shared)
+    {
+        immutable save = _rtLoading;
+        _rtLoading = true;
+        scope (exit) _rtLoading = save;
+
+        // if it's a D library
+        if (auto pdso = dsoForHandle(handle))
+            decThreadRef(pdso, true);
+    }
+    gcClrFn gcClr  = cast(gcClrFn) GetProcAddress(handle, "gc_clrProxy");
+    if (gcClr !is null)
+        gcClr();
+    return .FreeLibrary(handle) != 0;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// helper functions
+///////////////////////////////////////////////////////////////////////////////
+
+void initLocks() nothrow @nogc
+{
+    version (Shared)
+        InitializeCriticalSection(&_handleToDSOMutex);
+}
+
+void finiLocks() nothrow @nogc
+{
+    version (Shared)
+        DeleteCriticalSection(&_handleToDSOMutex);
+}
+
+void runModuleConstructors(DSO* pdso, bool runTlsCtors)
+{
+    pdso._moduleGroup.sortCtors();
+    pdso._moduleGroup.runCtors();
+    if (runTlsCtors) pdso._moduleGroup.runTlsCtors();
+}
+
+void runModuleDestructors(DSO* pdso, bool runTlsDtors)
+{
+    if (runTlsDtors) pdso._moduleGroup.runTlsDtors();
+    pdso._moduleGroup.runDtors();
+}
+
+void registerGCRanges(DSO* pdso) nothrow @nogc
+{
+    foreach (rng; pdso._gcRanges)
+        GC.addRange(rng.ptr, rng.length);
+}
+
+void unregisterGCRanges(DSO* pdso) nothrow @nogc
+{
+    foreach (rng; pdso._gcRanges)
+        GC.removeRange(rng.ptr);
+}
+
+version (Shared) void runFinalizers(DSO* pdso)
+{
+    foreach (seg; pdso._codeSegments)
+        GC.runFinalizers(seg);
+}
+
+void freeDSO(DSO* pdso) nothrow @nogc
+{
+    pdso._gcRanges.reset();
+    version (Shared)
+    {
+        pdso._codeSegments.reset();
+        pdso._deps.reset();
+        pdso._handle = null;
+    }
+    .free(pdso);
+}
+
+version (Shared)
+{
+@nogc nothrow:
+    const(char)* nameForDSO(DSO* pdso, ref char[] buffer)
+    {
+        const success = GetModuleFileNameA(pdso._handle, buffer.ptr, cast(DWORD)buffer.length) != 0;
+        safeAssert(success, "Failed to get DLL name.");
+        return buffer.ptr;
+    }
+
+    DSO* dsoForHandle(in void* handle)
+    {
+        DSO* pdso;
+        .EnterCriticalSection(&_handleToDSOMutex);
+        if (auto ppdso = handle in _handleToDSO)
+            pdso = *ppdso;
+        .LeaveCriticalSection(&_handleToDSOMutex);
+        return pdso;
+    }
+
+    void setDSOForHandle(DSO* pdso, void* handle)
+    {
+        .EnterCriticalSection(&_handleToDSOMutex);
+        safeAssert(handle !in _handleToDSO, "DSO already registered.");
+        _handleToDSO[handle] = pdso;
+        .LeaveCriticalSection(&_handleToDSOMutex);
+    }
+
+    void unsetDSOForHandle(DSO* pdso, void* handle)
+    {
+        .EnterCriticalSection(&_handleToDSOMutex);
+        safeAssert(_handleToDSO[handle] == pdso, "Handle doesn't match registered DSO.");
+        _handleToDSO.remove(handle);
+        .LeaveCriticalSection(&_handleToDSOMutex);
+    }
+
+    void getDependencies(in HMODULE handle, ref Array!(DSO*) deps)
+    {
+        auto nthdr = getNTHeader(handle);
+        auto import_entry = nthdr.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IMPORT];
+        auto addr = import_entry.VirtualAddress;
+        auto datasize = import_entry.Size;
+
+        if (addr == 0 && datasize == 0)
+        {
+            // Maybe the optional header isn't there, look for the section.
+            foreach (section; getSectionHeader(handle))
+            {
+                if (!compareSectionName(section, ".idata"))
+                    continue;
+                addr = section.VirtualAddress;
+                datasize = section.Misc.VirtualSize;
+                break;
+            }
+            if (datasize == 0)
+                return;
+        }
+        else
+        {
+            bool foundSection = false;
+            foreach (section; getSectionHeader(handle))
+            {
+                if (!compareSectionName(section, ".idata"))
+                    continue;
+                // Section containing import table has no contents.
+                if (section.Misc.VirtualSize == 0)
+                    return;
+                foundSection = true;
+                break;
+            }
+            // There is an import table, but the section containing it could not be found
+            if (!foundSection)
+                return;
+        }
+
+        // Get the names of each DLL
+        for (uint i = 0; i + IMAGE_IMPORT_DESCRIPTOR.sizeof <= datasize;
+             i += IMAGE_IMPORT_DESCRIPTOR.sizeof)
+        {
+            const data = cast(PIMAGE_IMPORT_DESCRIPTOR)(handle + addr + i);
+            if (data.Name == 0)
+                break;
+
+            // dll name of dependency
+            auto name = cast(char*)(handle + data.Name);
+            // get handle without loading the library
+            auto libhandle = handleForName(name);
+            // the runtime linker has already loaded all dependencies
+            safeAssert(handle !is null, "Failed to get library handle.");
+            // if it's a D library
+            if (auto pdso = dsoForHandle(handle))
+                deps.insertBack(pdso); // append it to the dependencies
+        }
+    }
+
+    void* handleForName(const char* name)
+    {
+        return GetModuleHandleA(name);
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////////
+// PE/COFF program header iteration
+///////////////////////////////////////////////////////////////////////////////
+
+bool compareSectionName(ref IMAGE_SECTION_HEADER section, string name) nothrow @nogc
+{
+    if (name[] != cast(char[])section.Name[0 .. name.length])
+        return false;
+    return name.length == 8 || section.Name[name.length] == 0;
+}
+
+/************
+ * Scan segments in the image header and store
+ * the writeable data segments in *pdso.
+ */
+
+void scanSegments(in HMODULE handle, DSO* pdso) nothrow @nogc
+{
+    foreach (section; getSectionHeader(handle))
+    {
+        // the ".data" image section includes both object file sections ".data" and ".bss"
+        if (compareSectionName(section, ".data"))
+        {
+            auto data = cast(void*)handle + section.VirtualAddress;
+            pdso._gcRanges.insertBack(data[0 .. section.Misc.VirtualSize]);
+            continue;
+        }
+
+        version (Shared)
+        {
+            if (compareSectionName(section, ".text"))
+            {
+                auto text = cast(void*)handle + section.VirtualAddress;
+                pdso._codeSegments.insertBack(text[0 .. section.Misc.VirtualSize]);
+                continue;
+            }
+        }
+    }
+}
+
+/**************************
+ * Input:
+ *      handle  where the output is to be written
+ * Returns:
+ *      true if found, and *handle is filled in
+ */
+
+bool findModuleHandleForAddr(in void* addr, out HMODULE handle) nothrow @nogc
+{
+    if (GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
+                           cast(const(wchar)*) addr, &handle))
+        return true;
+
+    return false;
+}
+
+/**
+ * Returns the image NT header for the HMODULE handle passed,
+ * or null if not found.
+ */
+PIMAGE_NT_HEADERS getNTHeader(in HMODULE handle) nothrow @nogc
+{
+    auto doshdr = cast(PIMAGE_DOS_HEADER)handle;
+    if (doshdr.e_magic != IMAGE_DOS_SIGNATURE)
+        return null;
+
+    return cast(typeof(return))(cast(void*)doshdr + doshdr.e_lfanew);
+}
+
+/**
+ * Returns the image section header for the HMODULE handle passed,
+ * or null if not found.
+ */
+IMAGE_SECTION_HEADER[] getSectionHeader(in HMODULE handle) nothrow @nogc
+{
+    if (auto nthdr = getNTHeader(handle))
+    {
+        const void* opthdr = &nthdr.OptionalHeader;
+        const offset = nthdr.FileHeader.SizeOfOptionalHeader;
+        const length = nthdr.FileHeader.NumberOfSections;
+        return (cast(PIMAGE_SECTION_HEADER)(opthdr + offset))[0 .. length];
+    }
+    return null;
+}
diff --git a/libphobos/libdruntime/gcc/sections/win32.d b/libphobos/libdruntime/gcc/sections/win32.d
deleted file mode 100644
index b355dfc..0000000
--- a/libphobos/libdruntime/gcc/sections/win32.d
+++ /dev/null
@@ -1,183 +0,0 @@
-// Win32-specific support for sections.
-// Copyright (C) 2019-2021 Free Software Foundation, Inc.
-
-// GCC is free software; you can redistribute it and/or modify it under
-// the terms of the GNU General Public License as published by the Free
-// Software Foundation; either version 3, or (at your option) any later
-// version.
-
-// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
-// WARRANTY; without even the implied warranty of MERCHANTABILITY or
-// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-// for more details.
-
-// Under Section 7 of GPL version 3, you are granted additional
-// permissions described in the GCC Runtime Library Exception, version
-// 3.1, as published by the Free Software Foundation.
-
-// You should have received a copy of the GNU General Public License and
-// a copy of the GCC Runtime Library Exception along with this program;
-// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
-// <http://www.gnu.org/licenses/>.
-
-module gcc.sections.win32;
-
-version (CRuntime_DigitalMars):
-
-// debug = PRINTF;
-debug(PRINTF) import core.stdc.stdio;
-import rt.minfo;
-import core.stdc.stdlib : malloc, free;
-
-struct SectionGroup
-{
-    static int opApply(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    static int opApplyReverse(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
-    {
-        return _moduleGroup.modules;
-    }
-
-    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
-    {
-        return _moduleGroup;
-    }
-
-    @property inout(void[])[] gcRanges() inout nothrow @nogc
-    {
-        return _gcRanges[];
-    }
-
-private:
-    ModuleGroup _moduleGroup;
-    void[][] _gcRanges;
-}
-
-shared(bool) conservative;
-
-void initSections() nothrow @nogc
-{
-    _sections._moduleGroup = ModuleGroup(getModuleInfos());
-
-    import rt.sections;
-    conservative = !scanDataSegPrecisely();
-
-    if (conservative)
-    {
-        _sections._gcRanges = (cast(void[]*) malloc(2 * (void[]).sizeof))[0..2];
-
-        auto databeg = cast(void*)&_xi_a;
-        auto dataend = cast(void*)_moduleinfo_array.ptr;
-        _sections._gcRanges[0] = databeg[0 .. dataend - databeg];
-
-        // skip module info and CONST segment
-        auto bssbeg = cast(void*)&_edata;
-        auto bssend = cast(void*)&_end;
-        _sections._gcRanges[1] = bssbeg[0 .. bssend - bssbeg];
-    }
-    else
-    {
-        size_t count = &_DPend - &_DPbegin;
-        auto ranges = cast(void[]*) malloc(count * (void[]).sizeof);
-        size_t r = 0;
-        void* prev = null;
-        for (size_t i = 0; i < count; i++)
-        {
-            void* addr = (&_DPbegin)[i];
-            if (prev + (void*).sizeof == addr)
-                ranges[r-1] = ranges[r-1].ptr[0 .. ranges[r-1].length + (void*).sizeof];
-            else
-                ranges[r++] = (cast(void**)addr)[0..1];
-            prev = addr;
-        }
-        _sections._gcRanges = ranges[0..r];
-    }
-}
-
-void finiSections() nothrow @nogc
-{
-    free(_sections._gcRanges.ptr);
-}
-
-void[] initTLSRanges() nothrow @nogc
-{
-    auto pbeg = cast(void*)&_tlsstart;
-    auto pend = cast(void*)&_tlsend;
-    return pbeg[0 .. pend - pbeg];
-}
-
-void finiTLSRanges(void[] rng) nothrow @nogc
-{
-}
-
-void scanTLSRanges(void[] rng, scope void delegate(void* pbeg, void* pend) nothrow dg) nothrow
-{
-    if (conservative)
-    {
-        dg(rng.ptr, rng.ptr + rng.length);
-    }
-    else
-    {
-        for (auto p = &_TPbegin; p < &_TPend; )
-        {
-            uint beg = *p++;
-            uint end = beg + cast(uint)((void*).sizeof);
-            while (p < &_TPend && *p == end)
-            {
-                end += (void*).sizeof;
-                p++;
-            }
-            dg(rng.ptr + beg, rng.ptr + end);
-        }
-    }
-}
-
-private:
-
-__gshared SectionGroup _sections;
-
-// Windows: this gets initialized by minit.asm
-extern(C) __gshared immutable(ModuleInfo*)[] _moduleinfo_array;
-extern(C) void _minit() nothrow @nogc;
-
-immutable(ModuleInfo*)[] getModuleInfos() nothrow @nogc
-out (result)
-{
-    foreach (m; result)
-        assert(m !is null);
-}
-body
-{
-    // _minit directly alters the global _moduleinfo_array
-    _minit();
-    return _moduleinfo_array;
-}
-
-extern(C)
-{
-    extern __gshared
-    {
-        int _xi_a;      // &_xi_a just happens to be start of data segment
-        int _edata;     // &_edata is start of BSS segment
-        int _end;       // &_end is past end of BSS
-
-        void* _DPbegin; // first entry in the array of pointers addresses
-        void* _DPend;   // &_DPend points after last entry of array
-        uint _TPbegin;  // first entry in the array of TLS offsets of pointers
-        uint _TPend;    // &_DPend points after last entry of array
-    }
-
-    extern
-    {
-        int _tlsstart;
-        int _tlsend;
-    }
-}
diff --git a/libphobos/libdruntime/gcc/sections/win64.d b/libphobos/libdruntime/gcc/sections/win64.d
deleted file mode 100644
index 357940b..0000000
--- a/libphobos/libdruntime/gcc/sections/win64.d
+++ /dev/null
@@ -1,321 +0,0 @@
-// Win64-specific support for sections.
-// Copyright (C) 2019-2021 Free Software Foundation, Inc.
-
-// GCC is free software; you can redistribute it and/or modify it under
-// the terms of the GNU General Public License as published by the Free
-// Software Foundation; either version 3, or (at your option) any later
-// version.
-
-// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
-// WARRANTY; without even the implied warranty of MERCHANTABILITY or
-// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
-// for more details.
-
-// Under Section 7 of GPL version 3, you are granted additional
-// permissions described in the GCC Runtime Library Exception, version
-// 3.1, as published by the Free Software Foundation.
-
-// You should have received a copy of the GNU General Public License and
-// a copy of the GCC Runtime Library Exception along with this program;
-// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
-// <http://www.gnu.org/licenses/>.
-
-module gcc.sections.win64;
-
-version (CRuntime_Microsoft):
-
-// debug = PRINTF;
-debug(PRINTF) import core.stdc.stdio;
-import core.stdc.stdlib : malloc, free;
-import rt.deh, rt.minfo;
-
-struct SectionGroup
-{
-    static int opApply(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    static int opApplyReverse(scope int delegate(ref SectionGroup) dg)
-    {
-        return dg(_sections);
-    }
-
-    @property immutable(ModuleInfo*)[] modules() const nothrow @nogc
-    {
-        return _moduleGroup.modules;
-    }
-
-    @property ref inout(ModuleGroup) moduleGroup() inout nothrow @nogc
-    {
-        return _moduleGroup;
-    }
-
-    version (Win64)
-    @property immutable(FuncTable)[] ehTables() const nothrow @nogc
-    {
-        auto pbeg = cast(immutable(FuncTable)*)&_deh_beg;
-        auto pend = cast(immutable(FuncTable)*)&_deh_end;
-        return pbeg[0 .. pend - pbeg];
-    }
-
-    @property inout(void[])[] gcRanges() inout nothrow @nogc
-    {
-        return _gcRanges[];
-    }
-
-private:
-    ModuleGroup _moduleGroup;
-    void[][] _gcRanges;
-}
-
-shared(bool) conservative;
-
-void initSections() nothrow @nogc
-{
-    _sections._moduleGroup = ModuleGroup(getModuleInfos());
-
-    // the ".data" image section includes both object file sections ".data" and ".bss"
-    void[] dataSection = findImageSection(".data");
-    debug(PRINTF) printf("found .data section: [%p,+%llx]\n", dataSection.ptr,
-                         cast(ulong)dataSection.length);
-
-    import rt.sections;
-    conservative = !scanDataSegPrecisely();
-
-    if (conservative)
-    {
-        _sections._gcRanges = (cast(void[]*) malloc((void[]).sizeof))[0..1];
-        _sections._gcRanges[0] = dataSection;
-    }
-    else
-    {
-        size_t count = &_DP_end - &_DP_beg;
-        auto ranges = cast(void[]*) malloc(count * (void[]).sizeof);
-        size_t r = 0;
-        void* prev = null;
-        for (size_t i = 0; i < count; i++)
-        {
-            auto off = (&_DP_beg)[i];
-            if (off == 0) // skip zero entries added by incremental linking
-                continue; // assumes there is no D-pointer at the very beginning of .data
-            void* addr = dataSection.ptr + off;
-            debug(PRINTF) printf("  scan %p\n", addr);
-            // combine consecutive pointers into single range
-            if (prev + (void*).sizeof == addr)
-                ranges[r-1] = ranges[r-1].ptr[0 .. ranges[r-1].length + (void*).sizeof];
-            else
-                ranges[r++] = (cast(void**)addr)[0..1];
-            prev = addr;
-        }
-        _sections._gcRanges = ranges[0..r];
-    }
-}
-
-void finiSections() nothrow @nogc
-{
-    .free(cast(void*)_sections.modules.ptr);
-    .free(_sections._gcRanges.ptr);
-}
-
-void[] initTLSRanges() nothrow @nogc
-{
-    void* pbeg;
-    void* pend;
-    // with VS2017 15.3.1, the linker no longer puts TLS segments into a
-    //  separate image section. That way _tls_start and _tls_end no
-    //  longer generate offsets into .tls, but DATA.
-    // Use the TEB entry to find the start of TLS instead and read the
-    //  length from the TLS directory
-    version (D_InlineAsm_X86)
-    {
-        asm @nogc nothrow
-        {
-            mov EAX, _tls_index;
-            mov ECX, FS:[0x2C];     // _tls_array
-            mov EAX, [ECX+4*EAX];
-            mov pbeg, EAX;
-            add EAX, [_tls_used+4]; // end
-            sub EAX, [_tls_used+0]; // start
-            mov pend, EAX;
-        }
-    }
-    else version (D_InlineAsm_X86_64)
-    {
-        asm @nogc nothrow
-        {
-            xor RAX, RAX;
-            mov EAX, _tls_index;
-            mov RCX, 0x58;
-            mov RCX, GS:[RCX];      // _tls_array (immediate value causes fixup)
-            mov RAX, [RCX+8*RAX];
-            mov pbeg, RAX;
-            add RAX, [_tls_used+8]; // end
-            sub RAX, [_tls_used+0]; // start
-            mov pend, RAX;
-        }
-    }
-    else
-        static assert(false, "Architecture not supported.");
-
-    return pbeg[0 .. pend - pbeg];
-}
-
-void finiTLSRanges(void[] rng) nothrow @nogc
-{
-}
-
-void scanTLSRanges(void[] rng, scope void delegate(void* pbeg, void* pend) nothrow dg) nothrow
-{
-    if (conservative)
-    {
-        dg(rng.ptr, rng.ptr + rng.length);
-    }
-    else
-    {
-        for (auto p = &_TP_beg; p < &_TP_end; )
-        {
-            uint beg = *p++;
-            uint end = beg + cast(uint)((void*).sizeof);
-            while (p < &_TP_end && *p == end)
-            {
-                end += (void*).sizeof;
-                p++;
-            }
-            dg(rng.ptr + beg, rng.ptr + end);
-        }
-    }
-}
-
-private:
-__gshared SectionGroup _sections;
-
-extern(C)
-{
-    extern __gshared void* _minfo_beg;
-    extern __gshared void* _minfo_end;
-}
-
-immutable(ModuleInfo*)[] getModuleInfos() nothrow @nogc
-out (result)
-{
-    foreach (m; result)
-        assert(m !is null);
-}
-body
-{
-    auto m = (cast(immutable(ModuleInfo*)*)&_minfo_beg)[1 .. &_minfo_end - &_minfo_beg];
-    /* Because of alignment inserted by the linker, various null pointers
-     * are there. We need to filter them out.
-     */
-    auto p = m.ptr;
-    auto pend = m.ptr + m.length;
-
-    // count non-null pointers
-    size_t cnt;
-    for (; p < pend; ++p)
-    {
-        if (*p !is null) ++cnt;
-    }
-
-    auto result = (cast(immutable(ModuleInfo)**).malloc(cnt * size_t.sizeof))[0 .. cnt];
-
-    p = m.ptr;
-    cnt = 0;
-    for (; p < pend; ++p)
-        if (*p !is null) result[cnt++] = *p;
-
-    return cast(immutable)result;
-}
-
-extern(C)
-{
-    /* Symbols created by the compiler/linker and inserted into the
-     * object file that 'bracket' sections.
-     */
-    extern __gshared
-    {
-        void* __ImageBase;
-
-        void* _deh_beg;
-        void* _deh_end;
-
-        uint _DP_beg;
-        uint _DP_end;
-        uint _TP_beg;
-        uint _TP_end;
-
-        void*[2] _tls_used; // start, end
-        int _tls_index;
-    }
-}
-
-/////////////////////////////////////////////////////////////////////
-
-enum IMAGE_DOS_SIGNATURE = 0x5A4D;      // MZ
-
-struct IMAGE_DOS_HEADER // DOS .EXE header
-{
-    ushort   e_magic;    // Magic number
-    ushort[29] e_res2;   // Reserved ushorts
-    int      e_lfanew;   // File address of new exe header
-}
-
-struct IMAGE_FILE_HEADER
-{
-    ushort Machine;
-    ushort NumberOfSections;
-    uint   TimeDateStamp;
-    uint   PointerToSymbolTable;
-    uint   NumberOfSymbols;
-    ushort SizeOfOptionalHeader;
-    ushort Characteristics;
-}
-
-struct IMAGE_NT_HEADERS
-{
-    uint Signature;
-    IMAGE_FILE_HEADER FileHeader;
-    // optional header follows
-}
-
-struct IMAGE_SECTION_HEADER
-{
-    char[8] Name = 0;
-    union {
-        uint   PhysicalAddress;
-        uint   VirtualSize;
-    }
-    uint   VirtualAddress;
-    uint   SizeOfRawData;
-    uint   PointerToRawData;
-    uint   PointerToRelocations;
-    uint   PointerToLinenumbers;
-    ushort NumberOfRelocations;
-    ushort NumberOfLinenumbers;
-    uint   Characteristics;
-}
-
-bool compareSectionName(ref IMAGE_SECTION_HEADER section, string name) nothrow @nogc
-{
-    if (name[] != section.Name[0 .. name.length])
-        return false;
-    return name.length == 8 || section.Name[name.length] == 0;
-}
-
-void[] findImageSection(string name) nothrow @nogc
-{
-    if (name.length > 8) // section name from string table not supported
-        return null;
-    IMAGE_DOS_HEADER* doshdr = cast(IMAGE_DOS_HEADER*) &__ImageBase;
-    if (doshdr.e_magic != IMAGE_DOS_SIGNATURE)
-        return null;
-
-    auto nthdr = cast(IMAGE_NT_HEADERS*)(cast(void*)doshdr + doshdr.e_lfanew);
-    auto sections = cast(IMAGE_SECTION_HEADER*)(cast(void*)nthdr + IMAGE_NT_HEADERS.sizeof + nthdr.FileHeader.SizeOfOptionalHeader);
-    for (ushort i = 0; i < nthdr.FileHeader.NumberOfSections; i++)
-        if (compareSectionName (sections[i], name))
-            return (cast(void*)&__ImageBase + sections[i].VirtualAddress)[0 .. sections[i].VirtualSize];
-
-    return null;
-}
diff --git a/libphobos/libdruntime/gcc/unwind/generic.d b/libphobos/libdruntime/gcc/unwind/generic.d
index 5315739..592b3af 100644
--- a/libphobos/libdruntime/gcc/unwind/generic.d
+++ b/libphobos/libdruntime/gcc/unwind/generic.d
@@ -269,6 +269,6 @@ version (GNU_SEH_Exceptions)
         ExceptionCollidedUnwind
     }
 
-    extern(C) EXCEPTION_DISPOSITION _GCC_specific_handler(void*, void*, void*,
+    extern(C) EXCEPTION_DISPOSITION _GCC_specific_handler(void*, void*, void*, void*,
                                                           _Unwind_Personality_Fn);
 }
diff --git a/libphobos/libdruntime/gcc/unwind/pe.d b/libphobos/libdruntime/gcc/unwind/pe.d
index 361ec12..b9b05cb 100644
--- a/libphobos/libdruntime/gcc/unwind/pe.d
+++ b/libphobos/libdruntime/gcc/unwind/pe.d
@@ -103,40 +103,37 @@ _Unwind_Ptr base_of_encoded_value(ubyte encoding, _Unwind_Context* context)
     assert(0);
 }
 
-// Read an unsigned leb128 value from P, *P is incremented past the value.
+// Read an unsigned leb128 value from P, P is incremented past the value.
 // We assume that a word is large enough to hold any value so encoded;
 // if it is smaller than a pointer on some target, pointers should not be
 // leb128 encoded on that target.
-_uleb128_t read_uleb128(const(ubyte)** p)
+_uleb128_t read_uleb128(ref const(ubyte)* p)
 {
-    auto q = *p;
     _uleb128_t result = 0;
     uint shift = 0;
 
     while (1)
     {
-        ubyte b = *q++;
+        ubyte b = *p++;
         result |= cast(_uleb128_t)(b & 0x7F) << shift;
         if ((b & 0x80) == 0)
             break;
         shift += 7;
     }
 
-    *p = q;
     return result;
 }
 
 // Similar, but read a signed leb128 value.
-_sleb128_t read_sleb128(const(ubyte)** p)
+_sleb128_t read_sleb128(ref const(ubyte)* p)
 {
-    auto q = *p;
     _sleb128_t result = 0;
     uint shift = 0;
     ubyte b = void;
 
     while (1)
     {
-        b = *q++;
+        b = *p++;
         result |= cast(_sleb128_t)(b & 0x7F) << shift;
         shift += 7;
         if ((b & 0x80) == 0)
@@ -147,69 +144,82 @@ _sleb128_t read_sleb128(const(ubyte)** p)
     if (shift < result.sizeof * 8 && (b & 0x40))
         result |= -(cast(_sleb128_t)1 << shift);
 
-    *p = q;
     return result;
 }
 
-// Load an encoded value from memory at P.  The value is returned in VAL;
-// The function returns P incremented past the value.  BASE is as given
+// Similar, but read an unaligned value of type T.
+pragma(inline, true)
+private T read_unaligned(T)(ref const(ubyte)* p)
+{
+    version (X86)         enum hasUnalignedLoads = true;
+    else version (X86_64) enum hasUnalignedLoads = true;
+    else                  enum hasUnalignedLoads = false;
+
+    static if (hasUnalignedLoads)
+    {
+        T result = *cast(T*)p;
+    }
+    else
+    {
+        import core.stdc.string : memcpy;
+        T result = void;
+        memcpy(&result, p, T.sizeof);
+    }
+    p += T.sizeof;
+    return result;
+}
+
+// Load an encoded value from memory at P.  The function returns the
+// encoded value.  P is incremented past the value.  BASE is as given
 // by base_of_encoded_value for this encoding in the appropriate context.
 _Unwind_Ptr read_encoded_value_with_base(ubyte encoding, _Unwind_Ptr base,
-                                         const(ubyte)** p)
+                                         ref const(ubyte)* p)
 {
-    auto q = *p;
+    auto psave = p;
     _Unwind_Internal_Ptr result;
 
     if (encoding == DW_EH_PE_aligned)
     {
-        _Unwind_Internal_Ptr a = cast(_Unwind_Internal_Ptr)q;
+        _Unwind_Internal_Ptr a = cast(_Unwind_Internal_Ptr)p;
         a = cast(_Unwind_Internal_Ptr)((a + (void*).sizeof - 1) & - (void*).sizeof);
         result = *cast(_Unwind_Internal_Ptr*)a;
-        q = cast(ubyte*) cast(_Unwind_Internal_Ptr)(a + (void*).sizeof);
+        p = cast(ubyte*) cast(_Unwind_Internal_Ptr)(a + (void*).sizeof);
     }
     else
     {
         switch (encoding & 0x0f)
         {
             case DW_EH_PE_uleb128:
-                result = cast(_Unwind_Internal_Ptr)read_uleb128(&q);
+                result = cast(_Unwind_Internal_Ptr)read_uleb128(p);
                 break;
 
             case DW_EH_PE_sleb128:
-                result = cast(_Unwind_Internal_Ptr)read_sleb128(&q);
+                result = cast(_Unwind_Internal_Ptr)read_sleb128(p);
                 break;
 
             case DW_EH_PE_udata2:
-                result = cast(_Unwind_Internal_Ptr) *cast(ushort*)q;
-                q += 2;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!ushort(p);
                 break;
             case DW_EH_PE_udata4:
-                result = cast(_Unwind_Internal_Ptr) *cast(uint*)q;
-                q += 4;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!uint(p);
                 break;
             case DW_EH_PE_udata8:
-                result = cast(_Unwind_Internal_Ptr) *cast(ulong*)q;
-                q += 8;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!ulong(p);
                 break;
 
             case DW_EH_PE_sdata2:
-                result = cast(_Unwind_Internal_Ptr) *cast(short*)q;
-                q += 2;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!short(p);
                 break;
             case DW_EH_PE_sdata4:
-                result = cast(_Unwind_Internal_Ptr) *cast(int*)q;
-                q += 4;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!int(p);
                 break;
             case DW_EH_PE_sdata8:
-                result = cast(_Unwind_Internal_Ptr) *cast(long*)q;
-                q += 8;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!long(p);
                 break;
 
             case DW_EH_PE_absptr:
-                if (size_t.sizeof == 8)
-                    goto case DW_EH_PE_udata8;
-                else
-                    goto case DW_EH_PE_udata4;
+                result = cast(_Unwind_Internal_Ptr)read_unaligned!(size_t)(p);
+                break;
 
             default:
                 __builtin_abort();
@@ -218,20 +228,19 @@ _Unwind_Ptr read_encoded_value_with_base(ubyte encoding, _Unwind_Ptr base,
         if (result != 0)
         {
             result += ((encoding & 0x70) == DW_EH_PE_pcrel
-                       ? cast(_Unwind_Internal_Ptr)*p : base);
+                       ? cast(_Unwind_Internal_Ptr)psave : base);
             if (encoding & DW_EH_PE_indirect)
                 result = *cast(_Unwind_Internal_Ptr*)result;
         }
     }
 
-    *p = q;
     return result;
 }
 
 // Like read_encoded_value_with_base, but get the base from the context
 // rather than providing it directly.
 _Unwind_Ptr read_encoded_value(_Unwind_Context* context, ubyte encoding,
-                               const(ubyte)** p)
+                               ref const(ubyte)* p)
 {
     auto base = base_of_encoded_value(encoding, context);
     return read_encoded_value_with_base(encoding, base, p);
diff --git a/libphobos/libdruntime/object.d b/libphobos/libdruntime/object.d
index 04d5457..e96d1c4 100644
--- a/libphobos/libdruntime/object.d
+++ b/libphobos/libdruntime/object.d
@@ -19,10 +19,11 @@ private
 alias size_t = typeof(int.sizeof);
 alias ptrdiff_t = typeof(cast(void*)0 - cast(void*)0);
 
-alias sizediff_t = ptrdiff_t; //For backwards compatibility only.
+alias sizediff_t = ptrdiff_t; // For backwards compatibility only.
+alias noreturn = typeof(*null);  /// bottom type
 
-alias hash_t = size_t; //For backwards compatibility only.
-alias equals_t = bool; //For backwards compatibility only.
+alias hash_t = size_t; // For backwards compatibility only.
+alias equals_t = bool; // For backwards compatibility only.
 
 alias string  = immutable(char)[];
 alias wstring = immutable(wchar)[];
@@ -41,7 +42,7 @@ else version (X86_64)
     else version (Windows) { /* no need for Win64 ABI */ }
     else version = WithArgTypes;
 }
-version (AArch64)
+else version (AArch64)
 {
     // Apple uses a trivial varargs implementation
     version (OSX) {}
diff --git a/libphobos/libdruntime/rt/dmain2.d b/libphobos/libdruntime/rt/dmain2.d
index 3d5ba29..e6acbd5 100644
--- a/libphobos/libdruntime/rt/dmain2.d
+++ b/libphobos/libdruntime/rt/dmain2.d
@@ -9,6 +9,9 @@
  * Source: $(DRUNTIMESRC src/rt/_dmain2.d)
  */
 
+/* NOTE: This file has been patched from the original DMD distribution to
+ * work with the GDC compiler.
+ */
 module rt.dmain2;
 
 private
@@ -70,70 +73,6 @@ version (CRuntime_Microsoft)
     extern(C) void init_msvc();
 }
 
-/***********************************
- * These are a temporary means of providing a GC hook for DLL use.  They may be
- * replaced with some other similar functionality later.
- */
-extern (C)
-{
-    void* gc_getProxy();
-    void  gc_setProxy(void* p);
-    void  gc_clrProxy();
-
-    alias void* function()      gcGetFn;
-    alias void  function(void*) gcSetFn;
-    alias void  function()      gcClrFn;
-}
-
-version (Windows)
-{
-    /*******************************************
-     * Loads a DLL written in D with the name 'name'.
-     * Returns:
-     *      opaque handle to the DLL if successfully loaded
-     *      null if failure
-     */
-    extern (C) void* rt_loadLibrary(const char* name)
-    {
-        return initLibrary(.LoadLibraryA(name));
-    }
-
-    extern (C) void* rt_loadLibraryW(const wchar_t* name)
-    {
-        return initLibrary(.LoadLibraryW(name));
-    }
-
-    void* initLibrary(void* mod)
-    {
-        // BUG: LoadLibrary() call calls rt_init(), which fails if proxy is not set!
-        // (What? LoadLibrary() is a Windows API call, it shouldn't call rt_init().)
-        if (mod is null)
-            return mod;
-        gcSetFn gcSet = cast(gcSetFn) GetProcAddress(mod, "gc_setProxy");
-        if (gcSet !is null)
-        {   // BUG: Set proxy, but too late
-            gcSet(gc_getProxy());
-        }
-        return mod;
-    }
-
-    /*************************************
-     * Unloads DLL that was previously loaded by rt_loadLibrary().
-     * Input:
-     *      ptr     the handle returned by rt_loadLibrary()
-     * Returns:
-     *      1   succeeded
-     *      0   some failure happened
-     */
-    extern (C) int rt_unloadLibrary(void* ptr)
-    {
-        gcClrFn gcClr  = cast(gcClrFn) GetProcAddress(ptr, "gc_clrProxy");
-        if (gcClr !is null)
-            gcClr();
-        return FreeLibrary(ptr) != 0;
-    }
-}
-
 /* To get out-of-band access to the args[] passed to main().
  */
 
diff --git a/libphobos/m4/autoconf.m4 b/libphobos/m4/autoconf.m4
index f46a780..f0ca947 100644
--- a/libphobos/m4/autoconf.m4
+++ b/libphobos/m4/autoconf.m4
@@ -27,7 +27,7 @@ AU_DEFUN([AC_LANG_D], [AC_LANG(D)])
 # AC_LANG_PROGRAM(D)([PROLOGUE], [BODY])
 # ---------------------------------------
 m4_define([AC_LANG_PROGRAM(D)],
-[module mod;
+[module object;
 $1
 
 extern(C) int main() {
diff --git a/libphobos/m4/druntime.m4 b/libphobos/m4/druntime.m4
index 7221712..2a7a689 100644
--- a/libphobos/m4/druntime.m4
+++ b/libphobos/m4/druntime.m4
@@ -116,3 +116,22 @@ AC_DEFUN([DRUNTIME_INSTALL_DIRECTORIES],
   gdc_include_dir='$(libdir)/gcc/${target_alias}/${gcc_version}/include/d'
   AC_SUBST(gdc_include_dir)
 ])
+
+# DRUNTIME_SECTION_FLAGS
+# ----------------------
+# Check for -ffunction-sections nad -fdata-sections.
+AC_DEFUN([DRUNTIME_SECTION_FLAGS],
+[
+  WITH_LOCAL_DRUNTIME([
+    AC_LANG_PUSH([D])
+    GDCFLAGS="$GDCFLAGS -g -Werror -ffunction-sections -fdata-sections"
+    AC_TRY_COMPILE([int foo; void bar() { }],[return 0;],
+		   [ac_fdsections=yes], [ac_fdsections=no])
+    if test "x$ac_fdsections" = "xyes"; then
+      SECTION_FLAGS='-ffunction-sections -fdata-sections'
+    fi
+    AC_MSG_RESULT($ac_fdsections)
+    AC_LANG_POP([D])
+  ], [-nophoboslib])
+  AC_SUBST(SECTION_FLAGS)
+])
diff --git a/libphobos/m4/druntime/libraries.m4 b/libphobos/m4/druntime/libraries.m4
index 743d3e3..45a56f6 100644
--- a/libphobos/m4/druntime/libraries.m4
+++ b/libphobos/m4/druntime/libraries.m4
@@ -116,7 +116,7 @@ AC_DEFUN([DRUNTIME_LIBRARIES_ATOMIC],
 
   DCFG_HAVE_LIBATOMIC=false
   LIBATOMIC=
-  AS_IF([test "x$with_libatomic" != "xno"], [
+  AS_IF([test "x$enable_libatomic" != "xno" && test "x$with_libatomic" != "xno"], [
     DCFG_HAVE_LIBATOMIC=true
     LIBATOMIC=../../libatomic/libatomic_convenience.la
   ], [
@@ -145,7 +145,7 @@ AC_DEFUN([DRUNTIME_LIBRARIES_BACKTRACE],
     AS_HELP_STRING([--without-libbacktrace],
                    [Do not use libbacktrace in core.runtime (default: auto)]))
 
-  AS_IF([test "x$with_libbacktrace" != "xno"], [
+  AS_IF([test "x$enable_libbacktrace" != "xno" && test "x$with_libbacktrace" != "xno"], [
     LIBBACKTRACE=../../libbacktrace/libbacktrace.la
 
     gdc_save_CPPFLAGS=$CPPFLAGS
diff --git a/libphobos/m4/druntime/os.m4 b/libphobos/m4/druntime/os.m4
index ed93e30..15cde3b 100644
--- a/libphobos/m4/druntime/os.m4
+++ b/libphobos/m4/druntime/os.m4
@@ -54,9 +54,10 @@ AC_DEFUN([DRUNTIME_OS_DETECT],
 
 # DRUNTIME_OS_SOURCES
 # -------------------
-# Detect target OS and add DRUNTIME_OS_AIX DRUNTIME_OS_DARWIN
-# DRUNTIME_OS_FREEBSD DRUNTIME_OS_LINUX DRUNTIME_OS_MINGW
-# DRUNTIME_OS_SOLARIS DRUNTIME_OS_OPENBSD conditionals.
+# Detect target OS and add DRUNTIME_OS_AIX DRUNTIME_OS_ANDROID
+# DRUNTIME_OS_DARWIN DRUNTIME_OS_DRAGONFLYBSD DRUNTIME_OS_FREEBSD
+# DRUNTIME_OS_LINUX DRUNTIME_OS_MINGW DRUNTIME_OS_NETBSD
+# DRUNTIME_OS_OPENBSD DRUNTIME_OS_SOLARIS conditionals.
 # If the system is posix, add DRUNTIME_OS_POSIX conditional.
 AC_DEFUN([DRUNTIME_OS_SOURCES],
 [
@@ -149,17 +150,31 @@ AC_DEFUN([DRUNTIME_OS_ARM_EABI_UNWINDER],
 # substitute DCFG_MINFO_BRACKETING.
 AC_DEFUN([DRUNTIME_OS_MINFO_BRACKETING],
 [
+  AC_REQUIRE([DRUNTIME_OS_DETECT])
+
   AC_LANG_PUSH([C])
   AC_MSG_CHECKING([for minfo section bracketing])
+  case "$druntime_cv_target_os" in
+      darwin*)
+	section="__DATA,__minfodata"
+	start="section\$start\$__DATA\$__minfodata"
+	stop="section\$end\$__DATA\$__minfodata"
+	;;
+      *)
+	section="minfo"
+	start="__start_minfo"
+	stop="__stop_minfo"
+	;;
+  esac
   AC_LINK_IFELSE([AC_LANG_SOURCE([
-    void* module_info_ptr __attribute__((section ("minfo")));
-    extern void* __start_minfo __attribute__((visibility ("hidden")));
-    extern void* __stop_minfo __attribute__((visibility ("hidden")));
+    void* module_info_ptr __attribute__((section ("$section")));
+    extern void* start_minfo __asm__("$start") __attribute__((visibility ("hidden")));
+    extern void* stop_minfo __asm__("$stop") __attribute__((visibility ("hidden")));
 
     int main()
     {
         // Never run, just to prevent compiler from optimizing access
-        return &__start_minfo == &__stop_minfo;
+        return (int)(&stop_minfo - &start_minfo);
     }
   ])],
     [AC_MSG_RESULT([yes])
diff --git a/libphobos/m4/gcc_support.m4 b/libphobos/m4/gcc_support.m4
index 0903ed4..cc1acb4 100644
--- a/libphobos/m4/gcc_support.m4
+++ b/libphobos/m4/gcc_support.m4
@@ -27,7 +27,7 @@ AC_DEFUN([PHOBOS_ABS_SRCDIR], [
 AC_DEFUN([WITH_LOCAL_DRUNTIME], [
   AC_REQUIRE([PHOBOS_ABS_SRCDIR])
   gdc_save_DFLAGS=$GDCFLAGS
-  GDCFLAGS="-fno-moduleinfo -nostdinc -I $phobos_cv_abs_srcdir/libdruntime $2 $GDCFLAGS"
+  GDCFLAGS="-fno-druntime -nostdinc -I $phobos_cv_abs_srcdir/libdruntime $2 $GDCFLAGS"
   $1
   GDCFLAGS=$gdc_save_DFLAGS
 ])
diff --git a/libphobos/src/MERGE b/libphobos/src/MERGE
index 6de04b4..01cf594 100644
--- a/libphobos/src/MERGE
+++ b/libphobos/src/MERGE
@@ -1,4 +1,4 @@
-9d575282edeccecbc061e615bf2486fd07e8c084
+55bb17543138a87c376a84745f2a30ec00bdecd9
 
 The first line of this file holds the git revision number of the last
 merge done from the dlang/phobos repository.
diff --git a/libphobos/src/Makefile.am b/libphobos/src/Makefile.am
index 2de8ab9..9f62510 100644
--- a/libphobos/src/Makefile.am
+++ b/libphobos/src/Makefile.am
@@ -24,8 +24,8 @@ D_EXTRA_DFLAGS=-nostdinc -I $(srcdir) \
 
 # D flags for compilation
 AM_DFLAGS= \
-	$(phobos_compiler_pic_flag) \
-	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(CET_DFLAGS)
+	$(phobos_lt_pic_flag) $(phobos_compiler_shared_flag) \
+	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(SECTION_FLAGS) $(CET_DFLAGS)
 
 # Flags for other kinds of sources
 AM_CFLAGS=$(CET_FLAGS)
@@ -45,8 +45,12 @@ libgphobos_la_SOURCES = $(ALL_PHOBOS_SOURCES)
 libgphobos_la_LIBTOOLFLAGS =
 libgphobos_la_LDFLAGS = -Wc,-nophoboslib,-dstartfiles,-B../libdruntime/gcc \
     -version-info $(libtool_VERSION)
+if ENABLE_LIBDRUNTIME_ONLY
+libgphobos_la_LIBADD = ../libdruntime/libgdruntime_convenience.la
+else
 libgphobos_la_LIBADD = \
     ../libdruntime/libgdruntime_convenience.la $(LIBZ)
+endif
 libgphobos_la_DEPENDENCIES = \
     ../libdruntime/libgdruntime_convenience.la libgphobos.spec
 
@@ -135,11 +139,11 @@ PHOBOS_DSOURCES = etc/c/curl.d etc/c/sqlite3.d etc/c/zlib.d \
 	std/regex/internal/backtracking.d std/regex/internal/generator.d \
 	std/regex/internal/ir.d std/regex/internal/kickstart.d \
 	std/regex/internal/parser.d std/regex/internal/tests.d \
-	std/regex/internal/thompson.d std/regex/package.d std/signals.d \
-	std/socket.d std/stdint.d std/stdio.d std/string.d std/system.d \
-	std/traits.d std/typecons.d std/typetuple.d std/uni.d std/uri.d \
-	std/utf.d std/uuid.d std/variant.d std/windows/charset.d \
-	std/windows/registry.d std/windows/syserror.d std/xml.d std/zip.d \
-	std/zlib.d
+	std/regex/internal/tests2.d std/regex/internal/thompson.d \
+	std/regex/package.d std/signals.d std/socket.d std/stdint.d \
+	std/stdio.d std/string.d std/system.d std/traits.d std/typecons.d \
+	std/typetuple.d std/uni.d std/uri.d std/utf.d std/uuid.d std/variant.d \
+	std/windows/charset.d std/windows/registry.d std/windows/syserror.d \
+	std/xml.d std/zip.d std/zlib.d
 
 endif
diff --git a/libphobos/src/Makefile.in b/libphobos/src/Makefile.in
index 2e72178..f8b7648 100644
--- a/libphobos/src/Makefile.in
+++ b/libphobos/src/Makefile.in
@@ -249,6 +249,7 @@ am__dirstamp = $(am__leading_dot)dirstamp
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/kickstart.lo \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/parser.lo \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/tests.lo \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/tests2.lo \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/thompson.lo \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/package.lo \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/signals.lo std/socket.lo \
@@ -387,6 +388,7 @@ PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
 RANLIB = @RANLIB@
+SECTION_FLAGS = @SECTION_FLAGS@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
 SHELL = @SHELL@
@@ -414,6 +416,8 @@ datadir = @datadir@
 datarootdir = @datarootdir@
 docdir = @docdir@
 dvidir = @dvidir@
+enable_shared = @enable_shared@
+enable_static = @enable_static@
 exec_prefix = @exec_prefix@
 gcc_version = @gcc_version@
 gdc_include_dir = @gdc_include_dir@
@@ -443,6 +447,7 @@ oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
 phobos_compiler_pic_flag = @phobos_compiler_pic_flag@
 phobos_compiler_shared_flag = @phobos_compiler_shared_flag@
+phobos_lt_pic_flag = @phobos_lt_pic_flag@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
@@ -477,8 +482,8 @@ D_EXTRA_DFLAGS = -nostdinc -I $(srcdir) \
 
 # D flags for compilation
 AM_DFLAGS = \
-	$(phobos_compiler_pic_flag) \
-	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(CET_DFLAGS)
+	$(phobos_lt_pic_flag) $(phobos_compiler_shared_flag) \
+	$(WARN_DFLAGS) $(CHECKING_DFLAGS) $(SECTION_FLAGS) $(CET_DFLAGS)
 
 
 # Flags for other kinds of sources
@@ -499,9 +504,10 @@ libgphobos_la_LIBTOOLFLAGS =
 libgphobos_la_LDFLAGS = -Wc,-nophoboslib,-dstartfiles,-B../libdruntime/gcc \
     -version-info $(libtool_VERSION)
 
-libgphobos_la_LIBADD = \
-    ../libdruntime/libgdruntime_convenience.la $(LIBZ)
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@libgphobos_la_LIBADD = \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@    ../libdruntime/libgdruntime_convenience.la $(LIBZ)
 
+@ENABLE_LIBDRUNTIME_ONLY_TRUE@libgphobos_la_LIBADD = ../libdruntime/libgdruntime_convenience.la
 libgphobos_la_DEPENDENCIES = \
     ../libdruntime/libgdruntime_convenience.la libgphobos.spec
 
@@ -569,12 +575,12 @@ libgphobos_la_LINK = $(LIBTOOL) --tag=D $(libgphobos_la_LIBTOOLFLAGS) \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/backtracking.d std/regex/internal/generator.d \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/ir.d std/regex/internal/kickstart.d \
 @ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/parser.d std/regex/internal/tests.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/thompson.d std/regex/package.d std/signals.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/socket.d std/stdint.d std/stdio.d std/string.d std/system.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/traits.d std/typecons.d std/typetuple.d std/uni.d std/uri.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/utf.d std/uuid.d std/variant.d std/windows/charset.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/windows/registry.d std/windows/syserror.d std/xml.d std/zip.d \
-@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/zlib.d
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/internal/tests2.d std/regex/internal/thompson.d \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/regex/package.d std/signals.d std/socket.d std/stdint.d \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/stdio.d std/string.d std/system.d std/traits.d std/typecons.d \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/typetuple.d std/uni.d std/uri.d std/utf.d std/uuid.d std/variant.d \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/windows/charset.d std/windows/registry.d std/windows/syserror.d \
+@ENABLE_LIBDRUNTIME_ONLY_FALSE@	std/xml.d std/zip.d std/zlib.d
 
 
 # Source file definitions. Boring stuff, auto-generated with
@@ -848,6 +854,7 @@ std/regex/internal/ir.lo: std/regex/internal/$(am__dirstamp)
 std/regex/internal/kickstart.lo: std/regex/internal/$(am__dirstamp)
 std/regex/internal/parser.lo: std/regex/internal/$(am__dirstamp)
 std/regex/internal/tests.lo: std/regex/internal/$(am__dirstamp)
+std/regex/internal/tests2.lo: std/regex/internal/$(am__dirstamp)
 std/regex/internal/thompson.lo: std/regex/internal/$(am__dirstamp)
 std/regex/$(am__dirstamp):
 	@$(MKDIR_P) std/regex
diff --git a/libphobos/src/std/algorithm/iteration.d b/libphobos/src/std/algorithm/iteration.d
index c77792d..19cfb77 100644
--- a/libphobos/src/std/algorithm/iteration.d
+++ b/libphobos/src/std/algorithm/iteration.d
@@ -769,9 +769,9 @@ private struct MapResult(alias fun, Range)
     string  s1 = "hello world!";
     dstring s2 = "日本語";
     dstring s3 = "hello world!"d;
-    auto ms1 = map!(std.ascii.toUpper)(s1);
-    auto ms2 = map!(std.ascii.toUpper)(s2);
-    auto ms3 = map!(std.ascii.toUpper)(s3);
+    auto ms1 = map!(toUpper)(s1);
+    auto ms2 = map!(toUpper)(s2);
+    auto ms3 = map!(toUpper)(s3);
     static assert(!is(ms1[0])); //narrow strings can't be indexed
     assert(ms2[0] == '日');
     assert(ms3[0] == 'H');
@@ -4450,7 +4450,7 @@ private struct SplitterResult(alias isTerminator, Range)
         ["là", "dove", "terminava", "quella", "valle"]
     ));
     assert(equal(
-        splitter!(std.uni.isWhite)("là dove terminava quella valle"),
+        splitter!(isWhite)("là dove terminava quella valle"),
         ["là", "dove", "terminava", "quella", "valle"]
     ));
     assert(equal(splitter!"a=='本'"("日本語"), ["日", "語"]));
diff --git a/libphobos/src/std/algorithm/searching.d b/libphobos/src/std/algorithm/searching.d
index 6468a87..09073f6 100644
--- a/libphobos/src/std/algorithm/searching.d
+++ b/libphobos/src/std/algorithm/searching.d
@@ -959,8 +959,8 @@ if (isInputRange!R &&
     import std.ascii : isDigit;
     import std.uni : isWhite;
 
-    assert(countUntil!(std.uni.isWhite)("hello world") == 5);
-    assert(countUntil!(std.ascii.isDigit)("hello world") == -1);
+    assert(countUntil!(isWhite)("hello world") == 5);
+    assert(countUntil!(isDigit)("hello world") == -1);
     assert(countUntil!"a > 20"([0, 7, 12, 22, 9]) == 3);
 }
 
diff --git a/libphobos/src/std/container/rbtree.d b/libphobos/src/std/container/rbtree.d
index 861da5e..5e31ac2 100644
--- a/libphobos/src/std/container/rbtree.d
+++ b/libphobos/src/std/container/rbtree.d
@@ -1814,8 +1814,8 @@ assert(equal(rbt[], [5]));
     test!byte();
 }
 
-import std.range.primitives : isInputRange, isSomeString, ElementType;
-import std.traits : isArray;
+import std.range.primitives : isInputRange, ElementType;
+import std.traits : isArray, isSomeString;
 
 /++
     Convenience function for creating a $(D RedBlackTree!E) from a list of
diff --git a/libphobos/src/std/conv.d b/libphobos/src/std/conv.d
index 31cc651..3560d13 100644
--- a/libphobos/src/std/conv.d
+++ b/libphobos/src/std/conv.d
@@ -3967,7 +3967,7 @@ if (isOctalLiteral(num))
 
 /// Ditto
 template octal(alias decimalInteger)
-if (isIntegral!(typeof(decimalInteger)))
+if (is(typeof(decimalInteger)) && isIntegral!(typeof(decimalInteger)))
 {
     enum octal = octal!(typeof(decimalInteger))(to!string(decimalInteger));
 }
diff --git a/libphobos/src/std/datetime/systime.d b/libphobos/src/std/datetime/systime.d
index b229191..913d360 100644
--- a/libphobos/src/std/datetime/systime.d
+++ b/libphobos/src/std/datetime/systime.d
@@ -9569,7 +9569,7 @@ afterMon: stripAndCheckLen(value[3 .. value.length], "1200:00A".length);
     }
 
     // year
-    auto found = value[2 .. value.length].find!(not!(std.ascii.isDigit))();
+    auto found = value[2 .. value.length].find!(not!(isDigit))();
     size_t yearLen = value.length - found.length;
     if (found.length == 0)
         throw new DateTimeException("Invalid year");
@@ -9659,7 +9659,7 @@ afterMon: stripAndCheckLen(value[3 .. value.length], "1200:00A".length);
             case "J": case "j": throw new DateTimeException("Invalid timezone");
             default:
             {
-                if (all!(std.ascii.isAlpha)(value[0 .. tzLen]))
+                if (all!(isAlpha)(value[0 .. tzLen]))
                 {
                     tz = new immutable SimpleTimeZone(Duration.zero);
                     break;
diff --git a/libphobos/src/std/experimental/logger/nulllogger.d b/libphobos/src/std/experimental/logger/nulllogger.d
index fa511be..0c55377 100644
--- a/libphobos/src/std/experimental/logger/nulllogger.d
+++ b/libphobos/src/std/experimental/logger/nulllogger.d
@@ -31,7 +31,7 @@ class NullLogger : Logger
 ///
 @safe unittest
 {
-    import std.experimental.logger.nulllogger : LogLevel;
+    import std.experimental.logger.core : LogLevel;
 
     auto nl1 = new NullLogger(LogLevel.all);
     nl1.info("You will never read this.");
diff --git a/libphobos/src/std/experimental/typecons.d b/libphobos/src/std/experimental/typecons.d
index 6906f05..07eed8f 100644
--- a/libphobos/src/std/experimental/typecons.d
+++ b/libphobos/src/std/experimental/typecons.d
@@ -23,8 +23,7 @@ module std.experimental.typecons;
 import std.meta; // : AliasSeq, allSatisfy;
 import std.traits;
 
-import std.typecons : Tuple, tuple, Bind, DerivedFunctionType,
-       isImplicitlyConvertible, mixinAll, staticIota,
+import std.typecons : Tuple, tuple, Bind, DerivedFunctionType, mixinAll, staticIota,
        GetOverloadedMethods;
 
 private
@@ -113,7 +112,8 @@ if (Targets.length >= 1 && allSatisfy!(isMutable, Targets))
             else
             {
                 enum foundFunc = findCovariantFunction!(TargetMembers[i], Source, SourceMembers);
-                debug
+                version (unittest) {}
+                else debug
                 {
                     static if (foundFunc == -1)
                         pragma(msg, "Could not locate matching function for: ",
diff --git a/libphobos/src/std/file.d b/libphobos/src/std/file.d
index 13a3db0..99530cb 100644
--- a/libphobos/src/std/file.d
+++ b/libphobos/src/std/file.d
@@ -2301,7 +2301,7 @@ if (isConvertibleToString!R)
 
 @safe unittest
 {
-    import std.path : mkdir;
+    import std.file : mkdir;
     static assert(__traits(compiles, mkdir(TestAliasedString(null))));
 }
 
@@ -4112,7 +4112,8 @@ auto dirEntries(string path, SpanMode mode, bool followSymlink = true)
     import std.algorithm.searching : startsWith;
     import std.array : array;
     import std.conv : to;
-    import std.path : dirEntries, buildPath, absolutePath;
+    import std.path : buildPath, absolutePath;
+    import std.file : dirEntries;
     import std.process : thisProcessID;
     import std.range.primitives : walkLength;
 
diff --git a/libphobos/src/std/format.d b/libphobos/src/std/format.d
index 64b1bd3..17e5906 100644
--- a/libphobos/src/std/format.d
+++ b/libphobos/src/std/format.d
@@ -5199,7 +5199,7 @@ body
     }
     debug (unformatRange) printf("\t");
     debug (unformatRange) if (!input.empty) printf("input.front = %c, ", input.front);
-    debug (unformatRange) printf("cont = %.*s\n", cont);
+    debug (unformatRange) printf("cont = %.*s\n", cast(int) cont.length, cont.ptr);
 
     bool checkEnd()
     {
@@ -5246,7 +5246,7 @@ body
             auto sep = spec.sep !is null ? spec.sep
                          : fmt.trailing;
             debug (unformatRange) {
-            if (!sep.empty && !input.empty) printf("-> %c, sep = %.*s\n", input.front, sep);
+            if (!sep.empty && !input.empty) printf("-> %c, sep = %.*s\n", input.front, cast(int) sep.length, sep.ptr);
             else                            printf("\n");
             }
 
diff --git a/libphobos/src/std/internal/math/biguintcore.d b/libphobos/src/std/internal/math/biguintcore.d
index f5cd769..6fc2d16 100644
--- a/libphobos/src/std/internal/math/biguintcore.d
+++ b/libphobos/src/std/internal/math/biguintcore.d
@@ -2503,13 +2503,13 @@ pure nothrow
     void printBiguint(const uint [] data)
     {
         char [] buff = biguintToHex(new char[data.length*9], data, '_');
-        printf("%.*s\n", buff.length, buff.ptr);
+        printf("%.*s\n", cast(int) buff.length, buff.ptr);
     }
 
     void printDecimalBigUint(BigUint data)
     {
         auto str = data.toDecimalString(0);
-        printf("%.*s\n", str.length, str.ptr);
+        printf("%.*s\n", cast(int) str.length, str.ptr);
     }
 
     uint [] a, b;
diff --git a/libphobos/src/std/math.d b/libphobos/src/std/math.d
index ff368b7..336c11a 100644
--- a/libphobos/src/std/math.d
+++ b/libphobos/src/std/math.d
@@ -263,8 +263,8 @@ version (unittest)
             alias real_t = double;
         else
             alias real_t = real;
-        ix = sprintf(bufx.ptr, "%.*Lg", ndigits, cast(real_t) x);
-        iy = sprintf(bufy.ptr, "%.*Lg", ndigits, cast(real_t) y);
+        ix = sprintf(bufx.ptr, is(real_t == real) ? "%.*Lg" : "%.*g", ndigits, cast(real_t) x);
+        iy = sprintf(bufy.ptr, is(real_t == real) ? "%.*Lg" : "%.*g", ndigits, cast(real_t) y);
         assert(ix < bufx.length && ix > 0);
         assert(ix < bufy.length && ix > 0);
 
diff --git a/libphobos/src/std/parallelism.d b/libphobos/src/std/parallelism.d
index 43a1ba5..61d5cea 100644
--- a/libphobos/src/std/parallelism.d
+++ b/libphobos/src/std/parallelism.d
@@ -4000,7 +4000,7 @@ version (unittest)
     import std.array : split;
     import std.conv : text;
     import std.exception : assertThrown;
-    import std.math : approxEqual, sqrt, log;
+    import std.math : approxEqual, sqrt, log, abs;
     import std.range : indexed, iota, join;
     import std.typecons : Tuple, tuple;
 
@@ -4329,7 +4329,7 @@ version (unittest)
 
     assert(equal(iota(1_000_000), bufTrickTest));
 
-    auto myTask = task!(std.math.abs)(-1);
+    auto myTask = task!(abs)(-1);
     taskPool.put(myTask);
     assert(myTask.spinForce == 1);
 
diff --git a/libphobos/src/std/process.d b/libphobos/src/std/process.d
index b0310a8..1e977aa 100644
--- a/libphobos/src/std/process.d
+++ b/libphobos/src/std/process.d
@@ -887,7 +887,7 @@ version (Windows) @system unittest
 // Searches the PATH variable for the given executable file,
 // (checking that it is in fact executable).
 version (Posix)
-private string searchPathFor(in char[] executable)
+package(std) string searchPathFor(in char[] executable)
     @trusted //TODO: @safe nothrow
 {
     import std.algorithm.iteration : splitter;
@@ -1358,7 +1358,8 @@ version (Windows)
 
 
 /**
-Flags that control the behaviour of $(LREF spawnProcess) and
+Flags that control the behaviour of process creation functions in this
+module. Most flags only apply to $(LREF spawnProcess) and
 $(LREF spawnShell).
 
 Use bitwise OR to combine flags.
@@ -1433,6 +1434,21 @@ enum Config
     Calling $(LREF wait) or $(LREF kill) with the resulting $(D Pid) is invalid.
     */
     detached = 64,
+
+    /**
+    By default, the $(LREF execute) and $(LREF executeShell) functions
+    will capture child processes' both stdout and stderr. This can be
+    undesirable if the standard output is to be processed or otherwise
+    used by the invoking program, as `execute`'s result would then
+    contain a mix of output and warning/error messages.
+
+    Specify this flag when calling `execute` or `executeShell` to
+    cause invoked processes' stderr stream to be sent to $(REF stderr,
+    std,stdio), and only capture and return standard output.
+
+    This flag has no effect on $(LREF spawnProcess) or $(LREF spawnShell).
+    */
+    stderrPassThrough = 128,
 }
 
 
@@ -2487,7 +2503,11 @@ private auto executeImpl(alias pipeFunc, Cmd, ExtraPipeFuncArgs...)(
     import std.array : appender;
     import std.typecons : Tuple;
 
-    auto p = pipeFunc(commandLine, Redirect.stdout | Redirect.stderrToStdout,
+    auto redirect = (config & Config.stderrPassThrough)
+        ? Redirect.stdout
+        : Redirect.stdout | Redirect.stderrToStdout;
+
+    auto p = pipeFunc(commandLine, redirect,
                       env, config, workDir, extraArgs);
 
     auto a = appender!(ubyte[])();
@@ -2551,6 +2571,31 @@ private auto executeImpl(alias pipeFunc, Cmd, ExtraPipeFuncArgs...)(
     assert(r3.output.empty);
 }
 
+@system unittest
+{
+    // Temporarily disable output to stderr so as to not spam the build log.
+    import std.stdio : stderr;
+    import std.typecons : Tuple;
+    import std.file : readText;
+    import std.traits : ReturnType;
+
+    ReturnType!executeShell r;
+    auto tmpname = uniqueTempPath;
+    scope(exit) if (exists(tmpname)) remove(tmpname);
+    auto t = stderr;
+    // Open a new scope to minimize code ran with stderr redirected.
+    {
+        stderr.open(tmpname, "w");
+        scope(exit) stderr = t;
+        r = executeShell("echo D rox>&2", null, Config.stderrPassThrough);
+    }
+    assert(r.status == 0);
+    assert(r.output.empty);
+    auto witness = readText(tmpname);
+    import std.ascii : newline;
+    assert(witness == "D rox" ~ newline, "'" ~ witness ~ "'");
+}
+
 @safe unittest
 {
     import std.typecons : Tuple;
@@ -2750,8 +2795,7 @@ private struct TestScript
     string path;
 }
 
-version (unittest)
-private string uniqueTempPath() @safe
+package(std) string uniqueTempPath() @safe
 {
     import std.file : tempDir;
     import std.path : buildPath;
diff --git a/libphobos/src/std/range/package.d b/libphobos/src/std/range/package.d
index 13601cb..deedb68 100644
--- a/libphobos/src/std/range/package.d
+++ b/libphobos/src/std/range/package.d
@@ -11379,7 +11379,6 @@ if (isInputRange!R && isIntegral!(ElementType!R))
         bw.popFront();
         assert(bw[2 * bitsNum - 3] == true);
 
-        import core.exception : Error;
         import std.exception : assertThrown;
 
         // Check out of bounds error
diff --git a/libphobos/src/std/regex/internal/tests.d b/libphobos/src/std/regex/internal/tests.d
index 1c4f295..fe75ce0 100644
--- a/libphobos/src/std/regex/internal/tests.d
+++ b/libphobos/src/std/regex/internal/tests.d
@@ -8,7 +8,7 @@ package(std.regex):
 import std.conv, std.exception, std.meta, std.range,
     std.typecons, std.regex;
 
-import std.regex.internal.parser : Escapables; // characters that need escaping
+import std.regex.internal.ir : Escapables; // characters that need escaping
 
 alias Sequence(int B, int E) = staticIota!(B, E);
 
@@ -467,654 +467,3 @@ alias Sequence(int B, int E) = staticIota!(B, E);
     run_tests!match(); //thompson VM
 }
 
-@safe unittest
-{
-    auto cr = ctRegex!("abc");
-    assert(bmatch("abc",cr).hit == "abc");
-    auto cr2 = ctRegex!("ab*c");
-    assert(bmatch("abbbbc",cr2).hit == "abbbbc");
-}
-@safe unittest
-{
-    auto cr3 = ctRegex!("^abc$");
-    assert(bmatch("abc",cr3).hit == "abc");
-    auto cr4 = ctRegex!(`\b(a\B[a-z]b)\b`);
-    assert(array(match("azb",cr4).captures) == ["azb", "azb"]);
-}
-
-@safe unittest
-{
-    auto cr5 = ctRegex!("(?:a{2,4}b{1,3}){1,2}");
-    assert(bmatch("aaabaaaabbb", cr5).hit == "aaabaaaabbb");
-    auto cr6 = ctRegex!("(?:a{2,4}b{1,3}){1,2}?"w);
-    assert(bmatch("aaabaaaabbb"w,  cr6).hit == "aaab"w);
-}
-
-@safe unittest
-{
-    auto cr7 = ctRegex!(`\r.*?$`,"sm");
-    assert(bmatch("abc\r\nxy",  cr7).hit == "\r\nxy");
-    auto greed =  ctRegex!("<packet.*?/packet>");
-    assert(bmatch("<packet>text</packet><packet>text</packet>", greed).hit
-            == "<packet>text</packet>");
-}
-
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto cr8 = ctRegex!("^(a)(b)?(c*)");
-    auto m8 = bmatch("abcc",cr8);
-    assert(m8);
-    assert(m8.captures[1] == "a");
-    assert(m8.captures[2] == "b");
-    assert(m8.captures[3] == "cc");
-    auto cr9 = ctRegex!("q(a|b)*q");
-    auto m9 = match("xxqababqyy",cr9);
-    assert(m9);
-    assert(equal(bmatch("xxqababqyy",cr9).captures, ["qababq", "b"]));
-}
-
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto rtr = regex("a|b|c");
-    enum ctr = regex("a|b|c");
-    assert(equal(rtr.ir,ctr.ir));
-    //CTFE parser BUG is triggered by group
-    //in the middle of alternation (at least not first and not last)
-    enum testCT = regex(`abc|(edf)|xyz`);
-    auto testRT = regex(`abc|(edf)|xyz`);
-    assert(equal(testCT.ir,testRT.ir));
-}
-
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    import std.algorithm.iteration : map;
-    enum cx = ctRegex!"(A|B|C)";
-    auto mx = match("B",cx);
-    assert(mx);
-    assert(equal(mx.captures, [ "B", "B"]));
-    enum cx2 = ctRegex!"(A|B)*";
-    assert(match("BAAA",cx2));
-
-    enum cx3 = ctRegex!("a{3,4}","i");
-    auto mx3 = match("AaA",cx3);
-    assert(mx3);
-    assert(mx3.captures[0] == "AaA");
-    enum cx4 = ctRegex!(`^a{3,4}?[a-zA-Z0-9~]{1,2}`,"i");
-    auto mx4 = match("aaaabc", cx4);
-    assert(mx4);
-    assert(mx4.captures[0] == "aaaab");
-    auto cr8 = ctRegex!("(a)(b)?(c*)");
-    auto m8 = bmatch("abcc",cr8);
-    assert(m8);
-    assert(m8.captures[1] == "a");
-    assert(m8.captures[2] == "b");
-    assert(m8.captures[3] == "cc");
-    auto cr9 = ctRegex!(".*$", "gm");
-    auto m9 = match("First\rSecond", cr9);
-    assert(m9);
-    assert(equal(map!"a.hit"(m9), ["First", "", "Second"]));
-}
-
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    import std.algorithm.iteration : map;
-//global matching
-    void test_body(alias matchFn)()
-    {
-        string s = "a quick brown fox jumps over a lazy dog";
-        auto r1 = regex("\\b[a-z]+\\b","g");
-        string[] test;
-        foreach (m; matchFn(s, r1))
-            test ~= m.hit;
-        assert(equal(test, [ "a", "quick", "brown", "fox", "jumps", "over", "a", "lazy", "dog"]));
-        auto free_reg = regex(`
-
-            abc
-            \s+
-            "
-            (
-                    [^"]+
-                |   \\ "
-            )+
-            "
-            z
-        `, "x");
-        auto m = match(`abc  "quoted string with \" inside"z`,free_reg);
-        assert(m);
-        string mails = " hey@you.com no@spam.net ";
-        auto rm = regex(`@(?<=\S+@)\S+`,"g");
-        assert(equal(map!"a[0]"(matchFn(mails, rm)), ["@you.com", "@spam.net"]));
-        auto m2 = matchFn("First line\nSecond line",regex(".*$","gm"));
-        assert(equal(map!"a[0]"(m2), ["First line", "", "Second line"]));
-        auto m2a = matchFn("First line\nSecond line",regex(".+$","gm"));
-        assert(equal(map!"a[0]"(m2a), ["First line", "Second line"]));
-        auto m2b = matchFn("First line\nSecond line",regex(".+?$","gm"));
-        assert(equal(map!"a[0]"(m2b), ["First line", "Second line"]));
-        debug(std_regex_test) writeln("!!! FReD FLAGS test done "~matchFn.stringof~" !!!");
-    }
-    test_body!bmatch();
-    test_body!match();
-}
-
-//tests for accumulated std.regex issues and other regressions
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    import std.algorithm.iteration : map;
-    void test_body(alias matchFn)()
-    {
-        //issue 5857
-        //matching goes out of control if ... in (...){x} has .*/.+
-        auto c = matchFn("axxxzayyyyyzd",regex("(a.*z){2}d")).captures;
-        assert(c[0] == "axxxzayyyyyzd");
-        assert(c[1] == "ayyyyyz");
-        auto c2 = matchFn("axxxayyyyyd",regex("(a.*){2}d")).captures;
-        assert(c2[0] == "axxxayyyyyd");
-        assert(c2[1] == "ayyyyy");
-        //issue 2108
-        //greedy vs non-greedy
-        auto nogreed = regex("<packet.*?/packet>");
-        assert(matchFn("<packet>text</packet><packet>text</packet>", nogreed).hit
-               == "<packet>text</packet>");
-        auto greed =  regex("<packet.*/packet>");
-        assert(matchFn("<packet>text</packet><packet>text</packet>", greed).hit
-               == "<packet>text</packet><packet>text</packet>");
-        //issue 4574
-        //empty successful match still advances the input
-        string[] pres, posts, hits;
-        foreach (m; matchFn("abcabc", regex("","g")))
-        {
-            pres ~= m.pre;
-            posts ~= m.post;
-            assert(m.hit.empty);
-
-        }
-        auto heads = [
-            "abcabc",
-            "abcab",
-            "abca",
-            "abc",
-            "ab",
-            "a",
-            ""
-        ];
-        auto tails = [
-            "abcabc",
-             "bcabc",
-              "cabc",
-               "abc",
-                "bc",
-                 "c",
-                  ""
-        ];
-        assert(pres == array(retro(heads)));
-        assert(posts == tails);
-        //issue 6076
-        //regression on .*
-        auto re = regex("c.*|d");
-        auto m = matchFn("mm", re);
-        assert(!m);
-        debug(std_regex_test) writeln("!!! FReD REGRESSION test done "~matchFn.stringof~" !!!");
-        auto rprealloc = regex(`((.){5}.{1,10}){5}`);
-        auto arr = array(repeat('0',100));
-        auto m2 = matchFn(arr, rprealloc);
-        assert(m2);
-        assert(collectException(
-                regex(r"^(import|file|binary|config)\s+([^\(]+)\(?([^\)]*)\)?\s*$")
-                ) is null);
-        foreach (ch; [Escapables])
-        {
-            assert(match(to!string(ch),regex(`[\`~ch~`]`)));
-            assert(!match(to!string(ch),regex(`[^\`~ch~`]`)));
-            assert(match(to!string(ch),regex(`[\`~ch~`-\`~ch~`]`)));
-        }
-        //bugzilla 7718
-        string strcmd = "./myApp.rb -os OSX -path \"/GIT/Ruby Apps/sec\" -conf 'notimer'";
-        auto reStrCmd = regex (`(".*")|('.*')`, "g");
-        assert(equal(map!"a[0]"(matchFn(strcmd, reStrCmd)),
-                     [`"/GIT/Ruby Apps/sec"`, `'notimer'`]));
-    }
-    test_body!bmatch();
-    test_body!match();
-}
-
-// tests for replace
-@safe unittest
-{
-    void test(alias matchFn)()
-    {
-        import std.uni : toUpper;
-
-        foreach (i, v; AliasSeq!(string, wstring, dstring))
-        {
-            auto baz(Cap)(Cap m)
-            if (is(Cap == Captures!(Cap.String)))
-            {
-                return toUpper(m.hit);
-            }
-            alias String = v;
-            assert(std.regex.replace!(matchFn)(to!String("ark rapacity"), regex(to!String("r")), to!String("c"))
-                   == to!String("ack rapacity"));
-            assert(std.regex.replace!(matchFn)(to!String("ark rapacity"), regex(to!String("r"), "g"), to!String("c"))
-                   == to!String("ack capacity"));
-            assert(std.regex.replace!(matchFn)(to!String("noon"), regex(to!String("^n")), to!String("[$&]"))
-                   == to!String("[n]oon"));
-            assert(std.regex.replace!(matchFn)(
-                to!String("test1 test2"), regex(to!String(`\w+`),"g"), to!String("$`:$'")
-            ) == to!String(": test2 test1 :"));
-            auto s = std.regex.replace!(baz!(Captures!(String)))(to!String("Strap a rocket engine on a chicken."),
-                    regex(to!String("[ar]"), "g"));
-            assert(s == "StRAp A Rocket engine on A chicken.");
-        }
-        debug(std_regex_test) writeln("!!! Replace test done "~matchFn.stringof~"  !!!");
-    }
-    test!(bmatch)();
-    test!(match)();
-}
-
-// tests for splitter
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto s1 = ", abc, de,     fg, hi, ";
-    auto sp1 = splitter(s1, regex(", *"));
-    auto w1 = ["", "abc", "de", "fg", "hi", ""];
-    assert(equal(sp1, w1));
-
-    auto s2 = ", abc, de,  fg, hi";
-    auto sp2 = splitter(s2, regex(", *"));
-    auto w2 = ["", "abc", "de", "fg", "hi"];
-
-    uint cnt;
-    foreach (e; sp2)
-    {
-        assert(w2[cnt++] == e);
-    }
-    assert(equal(sp2, w2));
-}
-
-@safe unittest
-{
-    char[] s1 = ", abc, de,  fg, hi, ".dup;
-    auto sp2 = splitter(s1, regex(", *"));
-}
-
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto s1 = ", abc, de,  fg, hi, ";
-    auto w1 = ["", "abc", "de", "fg", "hi", ""];
-    assert(equal(split(s1, regex(", *")), w1[]));
-}
-
-@safe unittest
-{ // bugzilla 7141
-    string pattern = `[a\--b]`;
-    assert(match("-", pattern));
-    assert(match("b", pattern));
-    string pattern2 = `[&-z]`;
-    assert(match("b", pattern2));
-}
-@safe unittest
-{//bugzilla 7111
-    assert(match("", regex("^")));
-}
-@safe unittest
-{//bugzilla 7300
-    assert(!match("a"d, "aa"d));
-}
-
-// bugzilla 7551
-@safe unittest
-{
-    auto r = regex("[]abc]*");
-    assert("]ab".matchFirst(r).hit == "]ab");
-    assertThrown(regex("[]"));
-    auto r2 = regex("[]abc--ab]*");
-    assert("]ac".matchFirst(r2).hit == "]");
-}
-
-@safe unittest
-{//bugzilla 7674
-    assert("1234".replace(regex("^"), "$$") == "$1234");
-    assert("hello?".replace(regex(r"\?", "g"), r"\?") == r"hello\?");
-    assert("hello?".replace(regex(r"\?", "g"), r"\\?") != r"hello\?");
-}
-@safe unittest
-{// bugzilla 7679
-    import std.algorithm.comparison : equal;
-    foreach (S; AliasSeq!(string, wstring, dstring))
-    (){ // avoid slow optimizations for large functions @@@BUG@@@ 2396
-        enum re = ctRegex!(to!S(r"\."));
-        auto str = to!S("a.b");
-        assert(equal(std.regex.splitter(str, re), [to!S("a"), to!S("b")]));
-        assert(split(str, re) == [to!S("a"), to!S("b")]);
-    }();
-}
-@safe unittest
-{//bugzilla 8203
-    string data = "
-    NAME   = XPAW01_STA:STATION
-    NAME   = XPAW01_STA
-    ";
-    auto uniFileOld = data;
-    auto r = regex(
-       r"^NAME   = (?P<comp>[a-zA-Z0-9_]+):*(?P<blk>[a-zA-Z0-9_]*)","gm");
-    auto uniCapturesNew = match(uniFileOld, r);
-    for (int i = 0; i < 20; i++)
-        foreach (matchNew; uniCapturesNew) {}
-    //a second issue with same symptoms
-    auto r2 = regex(`([а-яА-Я\-_]+\s*)+(?<=[\s\.,\^])`);
-    match("аллея Театральная", r2);
-}
-@safe unittest
-{// bugzilla 8637 purity of enforce
-    auto m = match("hello world", regex("world"));
-    enforce(m);
-}
-
-// bugzilla 8725
-@safe unittest
-{
-  static italic = regex( r"\*
-                (?!\s+)
-                (.*?)
-                (?!\s+)
-                \*", "gx" );
-  string input = "this * is* interesting, *very* interesting";
-  assert(replace(input, italic, "<i>$1</i>") ==
-      "this * is* interesting, <i>very</i> interesting");
-}
-
-// bugzilla 8349
-@safe unittest
-{
-    enum peakRegexStr = r"\>(wgEncode.*Tfbs.*\.(?:narrow)|(?:broad)Peak.gz)</a>";
-    enum peakRegex = ctRegex!(peakRegexStr);
-    //note that the regex pattern itself is probably bogus
-    assert(match(r"\>wgEncode-blah-Tfbs.narrow</a>", peakRegex));
-}
-
-// bugzilla 9211
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto rx_1 =  regex(r"^(\w)*(\d)");
-    auto m = match("1234", rx_1);
-    assert(equal(m.front, ["1234", "3", "4"]));
-    auto rx_2 = regex(r"^([0-9])*(\d)");
-    auto m2 = match("1234", rx_2);
-    assert(equal(m2.front, ["1234", "3", "4"]));
-}
-
-// bugzilla 9280
-@safe unittest
-{
-    string tomatch = "a!b@c";
-    static r = regex(r"^(?P<nick>.*?)!(?P<ident>.*?)@(?P<host>.*?)$");
-    auto nm = match(tomatch, r);
-    assert(nm);
-    auto c = nm.captures;
-    assert(c[1] == "a");
-    assert(c["nick"] == "a");
-}
-
-
-// bugzilla 9579
-@safe unittest
-{
-    char[] input = ['a', 'b', 'c'];
-    string format = "($1)";
-    // used to give a compile error:
-    auto re = regex(`(a)`, "g");
-    auto r = replace(input, re, format);
-    assert(r == "(a)bc");
-}
-
-// bugzilla 9634
-@safe unittest
-{
-    auto re = ctRegex!"(?:a+)";
-    assert(match("aaaa", re).hit == "aaaa");
-}
-
-//bugzilla 10798
-@safe unittest
-{
-    auto cr = ctRegex!("[abcd--c]*");
-    auto m  = "abc".match(cr);
-    assert(m);
-    assert(m.hit == "ab");
-}
-
-// bugzilla 10913
-@system unittest
-{
-    @system static string foo(const(char)[] s)
-    {
-        return s.dup;
-    }
-    @safe static string bar(const(char)[] s)
-    {
-        return s.dup;
-    }
-    () @system {
-        replace!((a) => foo(a.hit))("blah", regex(`a`));
-    }();
-    () @safe {
-        replace!((a) => bar(a.hit))("blah", regex(`a`));
-    }();
-}
-
-// bugzilla 11262
-@safe unittest
-{
-    enum reg = ctRegex!(r",", "g");
-    auto str = "This,List";
-    str = str.replace(reg, "-");
-    assert(str == "This-List");
-}
-
-// bugzilla 11775
-@safe unittest
-{
-    assert(collectException(regex("a{1,0}")));
-}
-
-// bugzilla 11839
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    assert(regex(`(?P<var1>\w+)`).namedCaptures.equal(["var1"]));
-    assert(collectException(regex(`(?P<1>\w+)`)));
-    assert(regex(`(?P<v1>\w+)`).namedCaptures.equal(["v1"]));
-    assert(regex(`(?P<__>\w+)`).namedCaptures.equal(["__"]));
-    assert(regex(`(?P<я>\w+)`).namedCaptures.equal(["я"]));
-}
-
-// bugzilla 12076
-@safe unittest
-{
-    auto RE = ctRegex!(r"(?<!x[a-z]+)\s([a-z]+)");
-    string s = "one two";
-    auto m = match(s, RE);
-}
-
-// bugzilla 12105
-@safe unittest
-{
-    auto r = ctRegex!`.*?(?!a)`;
-    assert("aaab".matchFirst(r).hit == "aaa");
-    auto r2 = ctRegex!`.*(?!a)`;
-    assert("aaab".matchFirst(r2).hit == "aaab");
-}
-
-//bugzilla 11784
-@safe unittest
-{
-    assert("abcdefghijklmnopqrstuvwxyz"
-        .matchFirst("[a-z&&[^aeiuo]]").hit == "b");
-}
-
-//bugzilla 12366
-@safe unittest
-{
-     auto re = ctRegex!(`^((?=(xx+?)\2+$)((?=\2+$)(?=(x+)(\4+$))\5){2})*x?$`);
-     assert("xxxxxxxx".match(re).empty);
-     assert(!"xxxx".match(re).empty);
-}
-
-// bugzilla 12582
-@safe unittest
-{
-    auto r = regex(`(?P<a>abc)`);
-    assert(collectException("abc".matchFirst(r)["b"]));
-}
-
-// bugzilla 12691
-@safe unittest
-{
-    assert(bmatch("e@", "^([a-z]|)*$").empty);
-    assert(bmatch("e@", ctRegex!`^([a-z]|)*$`).empty);
-}
-
-//bugzilla  12713
-@safe unittest
-{
-    assertThrown(regex("[[a-z]([a-z]|(([[a-z])))"));
-}
-
-//bugzilla 12747
-@safe unittest
-{
-    assertThrown(regex(`^x(\1)`));
-    assertThrown(regex(`^(x(\1))`));
-    assertThrown(regex(`^((x)(?=\1))`));
-}
-
-// bugzilla 14504
-@safe unittest
-{
-    auto p = ctRegex!("a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?" ~
-            "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
-}
-
-// bugzilla 14529
-@safe unittest
-{
-    auto ctPat2 = regex(r"^[CDF]$", "i");
-    foreach (v; ["C", "c", "D", "d", "F", "f"])
-        assert(matchAll(v, ctPat2).front.hit == v);
-}
-
-// bugzilla 14615
-@safe unittest
-{
-    import std.array : appender;
-    import std.regex : replaceFirst, replaceFirstInto, regex;
-    import std.stdio : writeln;
-
-    auto example = "Hello, world!";
-    auto pattern = regex("^Hello, (bug)");  // won't find this one
-    auto result = replaceFirst(example, pattern, "$1 Sponge Bob");
-    assert(result == "Hello, world!");  // Ok.
-
-    auto sink = appender!string;
-    replaceFirstInto(sink, example, pattern, "$1 Sponge Bob");
-    assert(sink.data == "Hello, world!");
-    replaceAllInto(sink, example, pattern, "$1 Sponge Bob");
-    assert(sink.data == "Hello, world!Hello, world!");
-}
-
-// bugzilla 15573
-@safe unittest
-{
-    auto rx = regex("[c d]", "x");
-    assert("a b".matchFirst(rx));
-}
-
-// bugzilla 15864
-@safe unittest
-{
-    regex(`(<a (?:(?:\w+=\"[^"]*\")?\s*)*href="\.\.?)"`);
-}
-
-@safe unittest
-{
-    auto r = regex("(?# comment)abc(?# comment2)");
-    assert("abc".matchFirst(r));
-    assertThrown(regex("(?#..."));
-}
-
-// bugzilla 17075
-@safe unittest
-{
-    enum titlePattern = `<title>(.+)</title>`;
-    static titleRegex = ctRegex!titlePattern;
-    string input = "<title>" ~ "<".repeat(100_000).join;
-    assert(input.matchFirst(titleRegex).empty);
-}
-
-// bugzilla 17212
-@safe unittest
-{
-    auto r = regex(" [a] ", "x");
-    assert("a".matchFirst(r));
-}
-
-// bugzilla 17157
-@safe unittest
-{
-    import std.algorithm.comparison : equal;
-    auto ctr = ctRegex!"(a)|(b)|(c)|(d)";
-    auto r = regex("(a)|(b)|(c)|(d)", "g");
-    auto s = "--a--b--c--d--";
-    auto outcomes = [
-        ["a", "a", "", "", ""],
-        ["b", "", "b", "", ""],
-        ["c", "", "", "c", ""],
-        ["d", "", "", "", "d"]
-    ];
-    assert(equal!equal(s.matchAll(ctr), outcomes));
-    assert(equal!equal(s.bmatch(r), outcomes));
-}
-
-// bugzilla 17667
-@safe unittest
-{
-    import std.algorithm.searching : canFind;
-    void willThrow(T, size_t line = __LINE__)(T arg, string msg)
-    {
-        auto e = collectException(regex(arg));
-        assert(e.msg.canFind(msg), to!string(line) ~ ": " ~ e.msg);
-    }
-    willThrow([r".", r"[\(\{[\]\}\)]"], "no matching ']' found while parsing character class");
-    willThrow([r"[\", r"123"], "no matching ']' found while parsing character class");
-    willThrow([r"[a-", r"123"], "no matching ']' found while parsing character class");
-    willThrow([r"[a-\", r"123"], "invalid escape sequence");
-    willThrow([r"\", r"123"], "invalid escape sequence");
-}
-
-// bugzilla 17668
-@safe unittest
-{
-    import std.algorithm.searching;
-    auto e = collectException!RegexException(regex(q"<[^]>"));
-    assert(e.msg.canFind("no operand for '^'"));
-}
-
-// bugzilla 17673
-@safe unittest
-{
-    string str = `<">`;
-    string[] regexps = ["abc", "\"|x"];
-    auto regexp = regex(regexps);
-    auto c = matchFirst(str, regexp);
-    assert(c);
-    assert(c.whichPattern == 2);
-}
-
diff --git a/libphobos/src/std/regex/internal/tests2.d b/libphobos/src/std/regex/internal/tests2.d
new file mode 100644
index 0000000..420f8d3
--- /dev/null
+++ b/libphobos/src/std/regex/internal/tests2.d
@@ -0,0 +1,662 @@
+// Split-up due to DMD's enormous memory consumption
+
+module std.regex.internal.tests2;
+
+package(std.regex):
+
+import std.conv, std.exception, std.meta, std.range,
+    std.typecons, std.regex;
+
+import std.regex.internal.ir : Escapables; // characters that need escaping
+
+@safe unittest
+{
+    auto cr = ctRegex!("abc");
+    assert(bmatch("abc",cr).hit == "abc");
+    auto cr2 = ctRegex!("ab*c");
+    assert(bmatch("abbbbc",cr2).hit == "abbbbc");
+}
+@safe unittest
+{
+    auto cr3 = ctRegex!("^abc$");
+    assert(bmatch("abc",cr3).hit == "abc");
+    auto cr4 = ctRegex!(`\b(a\B[a-z]b)\b`);
+    assert(array(match("azb",cr4).captures) == ["azb", "azb"]);
+}
+
+@safe unittest
+{
+    auto cr5 = ctRegex!("(?:a{2,4}b{1,3}){1,2}");
+    assert(bmatch("aaabaaaabbb", cr5).hit == "aaabaaaabbb");
+    auto cr6 = ctRegex!("(?:a{2,4}b{1,3}){1,2}?"w);
+    assert(bmatch("aaabaaaabbb"w,  cr6).hit == "aaab"w);
+}
+
+@safe unittest
+{
+    auto cr7 = ctRegex!(`\r.*?$`,"sm");
+    assert(bmatch("abc\r\nxy",  cr7).hit == "\r\nxy");
+    auto greed =  ctRegex!("<packet.*?/packet>");
+    assert(bmatch("<packet>text</packet><packet>text</packet>", greed).hit
+            == "<packet>text</packet>");
+}
+
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto cr8 = ctRegex!("^(a)(b)?(c*)");
+    auto m8 = bmatch("abcc",cr8);
+    assert(m8);
+    assert(m8.captures[1] == "a");
+    assert(m8.captures[2] == "b");
+    assert(m8.captures[3] == "cc");
+    auto cr9 = ctRegex!("q(a|b)*q");
+    auto m9 = match("xxqababqyy",cr9);
+    assert(m9);
+    assert(equal(bmatch("xxqababqyy",cr9).captures, ["qababq", "b"]));
+}
+
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto rtr = regex("a|b|c");
+    enum ctr = regex("a|b|c");
+    assert(equal(rtr.ir,ctr.ir));
+    //CTFE parser BUG is triggered by group
+    //in the middle of alternation (at least not first and not last)
+    enum testCT = regex(`abc|(edf)|xyz`);
+    auto testRT = regex(`abc|(edf)|xyz`);
+    assert(equal(testCT.ir,testRT.ir));
+}
+
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    import std.algorithm.iteration : map;
+    enum cx = ctRegex!"(A|B|C)";
+    auto mx = match("B",cx);
+    assert(mx);
+    assert(equal(mx.captures, [ "B", "B"]));
+    enum cx2 = ctRegex!"(A|B)*";
+    assert(match("BAAA",cx2));
+
+    enum cx3 = ctRegex!("a{3,4}","i");
+    auto mx3 = match("AaA",cx3);
+    assert(mx3);
+    assert(mx3.captures[0] == "AaA");
+    enum cx4 = ctRegex!(`^a{3,4}?[a-zA-Z0-9~]{1,2}`,"i");
+    auto mx4 = match("aaaabc", cx4);
+    assert(mx4);
+    assert(mx4.captures[0] == "aaaab");
+    auto cr8 = ctRegex!("(a)(b)?(c*)");
+    auto m8 = bmatch("abcc",cr8);
+    assert(m8);
+    assert(m8.captures[1] == "a");
+    assert(m8.captures[2] == "b");
+    assert(m8.captures[3] == "cc");
+    auto cr9 = ctRegex!(".*$", "gm");
+    auto m9 = match("First\rSecond", cr9);
+    assert(m9);
+    assert(equal(map!"a.hit"(m9), ["First", "", "Second"]));
+}
+
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    import std.algorithm.iteration : map;
+//global matching
+    void test_body(alias matchFn)()
+    {
+        string s = "a quick brown fox jumps over a lazy dog";
+        auto r1 = regex("\\b[a-z]+\\b","g");
+        string[] test;
+        foreach (m; matchFn(s, r1))
+            test ~= m.hit;
+        assert(equal(test, [ "a", "quick", "brown", "fox", "jumps", "over", "a", "lazy", "dog"]));
+        auto free_reg = regex(`
+
+            abc
+            \s+
+            "
+            (
+                    [^"]+
+                |   \\ "
+            )+
+            "
+            z
+        `, "x");
+        auto m = match(`abc  "quoted string with \" inside"z`,free_reg);
+        assert(m);
+        string mails = " hey@you.com no@spam.net ";
+        auto rm = regex(`@(?<=\S+@)\S+`,"g");
+        assert(equal(map!"a[0]"(matchFn(mails, rm)), ["@you.com", "@spam.net"]));
+        auto m2 = matchFn("First line\nSecond line",regex(".*$","gm"));
+        assert(equal(map!"a[0]"(m2), ["First line", "", "Second line"]));
+        auto m2a = matchFn("First line\nSecond line",regex(".+$","gm"));
+        assert(equal(map!"a[0]"(m2a), ["First line", "Second line"]));
+        auto m2b = matchFn("First line\nSecond line",regex(".+?$","gm"));
+        assert(equal(map!"a[0]"(m2b), ["First line", "Second line"]));
+        debug(std_regex_test) writeln("!!! FReD FLAGS test done "~matchFn.stringof~" !!!");
+    }
+    test_body!bmatch();
+    test_body!match();
+}
+
+//tests for accumulated std.regex issues and other regressions
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    import std.algorithm.iteration : map;
+    void test_body(alias matchFn)()
+    {
+        //issue 5857
+        //matching goes out of control if ... in (...){x} has .*/.+
+        auto c = matchFn("axxxzayyyyyzd",regex("(a.*z){2}d")).captures;
+        assert(c[0] == "axxxzayyyyyzd");
+        assert(c[1] == "ayyyyyz");
+        auto c2 = matchFn("axxxayyyyyd",regex("(a.*){2}d")).captures;
+        assert(c2[0] == "axxxayyyyyd");
+        assert(c2[1] == "ayyyyy");
+        //issue 2108
+        //greedy vs non-greedy
+        auto nogreed = regex("<packet.*?/packet>");
+        assert(matchFn("<packet>text</packet><packet>text</packet>", nogreed).hit
+               == "<packet>text</packet>");
+        auto greed =  regex("<packet.*/packet>");
+        assert(matchFn("<packet>text</packet><packet>text</packet>", greed).hit
+               == "<packet>text</packet><packet>text</packet>");
+        //issue 4574
+        //empty successful match still advances the input
+        string[] pres, posts, hits;
+        foreach (m; matchFn("abcabc", regex("","g")))
+        {
+            pres ~= m.pre;
+            posts ~= m.post;
+            assert(m.hit.empty);
+
+        }
+        auto heads = [
+            "abcabc",
+            "abcab",
+            "abca",
+            "abc",
+            "ab",
+            "a",
+            ""
+        ];
+        auto tails = [
+            "abcabc",
+             "bcabc",
+              "cabc",
+               "abc",
+                "bc",
+                 "c",
+                  ""
+        ];
+        assert(pres == array(retro(heads)));
+        assert(posts == tails);
+        //issue 6076
+        //regression on .*
+        auto re = regex("c.*|d");
+        auto m = matchFn("mm", re);
+        assert(!m);
+        debug(std_regex_test) writeln("!!! FReD REGRESSION test done "~matchFn.stringof~" !!!");
+        auto rprealloc = regex(`((.){5}.{1,10}){5}`);
+        auto arr = array(repeat('0',100));
+        auto m2 = matchFn(arr, rprealloc);
+        assert(m2);
+        assert(collectException(
+                regex(r"^(import|file|binary|config)\s+([^\(]+)\(?([^\)]*)\)?\s*$")
+                ) is null);
+        foreach (ch; [Escapables])
+        {
+            assert(match(to!string(ch),regex(`[\`~ch~`]`)));
+            assert(!match(to!string(ch),regex(`[^\`~ch~`]`)));
+            assert(match(to!string(ch),regex(`[\`~ch~`-\`~ch~`]`)));
+        }
+        //bugzilla 7718
+        string strcmd = "./myApp.rb -os OSX -path \"/GIT/Ruby Apps/sec\" -conf 'notimer'";
+        auto reStrCmd = regex (`(".*")|('.*')`, "g");
+        assert(equal(map!"a[0]"(matchFn(strcmd, reStrCmd)),
+                     [`"/GIT/Ruby Apps/sec"`, `'notimer'`]));
+    }
+    test_body!bmatch();
+    test_body!match();
+}
+
+// tests for replace
+@safe unittest
+{
+    void test(alias matchFn)()
+    {
+        import std.uni : toUpper;
+
+        foreach (i, v; AliasSeq!(string, wstring, dstring))
+        {
+            auto baz(Cap)(Cap m)
+            if (is(Cap == Captures!(Cap.String)))
+            {
+                return toUpper(m.hit);
+            }
+            alias String = v;
+            assert(std.regex.replace!(matchFn)(to!String("ark rapacity"), regex(to!String("r")), to!String("c"))
+                   == to!String("ack rapacity"));
+            assert(std.regex.replace!(matchFn)(to!String("ark rapacity"), regex(to!String("r"), "g"), to!String("c"))
+                   == to!String("ack capacity"));
+            assert(std.regex.replace!(matchFn)(to!String("noon"), regex(to!String("^n")), to!String("[$&]"))
+                   == to!String("[n]oon"));
+            assert(std.regex.replace!(matchFn)(
+                to!String("test1 test2"), regex(to!String(`\w+`),"g"), to!String("$`:$'")
+            ) == to!String(": test2 test1 :"));
+            auto s = std.regex.replace!(baz!(Captures!(String)))(to!String("Strap a rocket engine on a chicken."),
+                    regex(to!String("[ar]"), "g"));
+            assert(s == "StRAp A Rocket engine on A chicken.");
+        }
+        debug(std_regex_test) writeln("!!! Replace test done "~matchFn.stringof~"  !!!");
+    }
+    test!(bmatch)();
+    test!(match)();
+}
+
+// tests for splitter
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto s1 = ", abc, de,     fg, hi, ";
+    auto sp1 = splitter(s1, regex(", *"));
+    auto w1 = ["", "abc", "de", "fg", "hi", ""];
+    assert(equal(sp1, w1));
+
+    auto s2 = ", abc, de,  fg, hi";
+    auto sp2 = splitter(s2, regex(", *"));
+    auto w2 = ["", "abc", "de", "fg", "hi"];
+
+    uint cnt;
+    foreach (e; sp2)
+    {
+        assert(w2[cnt++] == e);
+    }
+    assert(equal(sp2, w2));
+}
+
+@safe unittest
+{
+    char[] s1 = ", abc, de,  fg, hi, ".dup;
+    auto sp2 = splitter(s1, regex(", *"));
+}
+
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto s1 = ", abc, de,  fg, hi, ";
+    auto w1 = ["", "abc", "de", "fg", "hi", ""];
+    assert(equal(split(s1, regex(", *")), w1[]));
+}
+
+@safe unittest
+{ // bugzilla 7141
+    string pattern = `[a\--b]`;
+    assert(match("-", pattern));
+    assert(match("b", pattern));
+    string pattern2 = `[&-z]`;
+    assert(match("b", pattern2));
+}
+@safe unittest
+{//bugzilla 7111
+    assert(match("", regex("^")));
+}
+@safe unittest
+{//bugzilla 7300
+    assert(!match("a"d, "aa"d));
+}
+
+// bugzilla 7551
+@safe unittest
+{
+    auto r = regex("[]abc]*");
+    assert("]ab".matchFirst(r).hit == "]ab");
+    assertThrown(regex("[]"));
+    auto r2 = regex("[]abc--ab]*");
+    assert("]ac".matchFirst(r2).hit == "]");
+}
+
+@safe unittest
+{//bugzilla 7674
+    assert("1234".replace(regex("^"), "$$") == "$1234");
+    assert("hello?".replace(regex(r"\?", "g"), r"\?") == r"hello\?");
+    assert("hello?".replace(regex(r"\?", "g"), r"\\?") != r"hello\?");
+}
+@safe unittest
+{// bugzilla 7679
+    import std.algorithm.comparison : equal;
+    foreach (S; AliasSeq!(string, wstring, dstring))
+    (){ // avoid slow optimizations for large functions @@@BUG@@@ 2396
+        enum re = ctRegex!(to!S(r"\."));
+        auto str = to!S("a.b");
+        assert(equal(std.regex.splitter(str, re), [to!S("a"), to!S("b")]));
+        assert(split(str, re) == [to!S("a"), to!S("b")]);
+    }();
+}
+@safe unittest
+{//bugzilla 8203
+    string data = "
+    NAME   = XPAW01_STA:STATION
+    NAME   = XPAW01_STA
+    ";
+    auto uniFileOld = data;
+    auto r = regex(
+       r"^NAME   = (?P<comp>[a-zA-Z0-9_]+):*(?P<blk>[a-zA-Z0-9_]*)","gm");
+    auto uniCapturesNew = match(uniFileOld, r);
+    for (int i = 0; i < 20; i++)
+        foreach (matchNew; uniCapturesNew) {}
+    //a second issue with same symptoms
+    auto r2 = regex(`([а-яА-Я\-_]+\s*)+(?<=[\s\.,\^])`);
+    match("аллея Театральная", r2);
+}
+@safe unittest
+{// bugzilla 8637 purity of enforce
+    auto m = match("hello world", regex("world"));
+    enforce(m);
+}
+
+// bugzilla 8725
+@safe unittest
+{
+  static italic = regex( r"\*
+                (?!\s+)
+                (.*?)
+                (?!\s+)
+                \*", "gx" );
+  string input = "this * is* interesting, *very* interesting";
+  assert(replace(input, italic, "<i>$1</i>") ==
+      "this * is* interesting, <i>very</i> interesting");
+}
+
+// bugzilla 8349
+@safe unittest
+{
+    enum peakRegexStr = r"\>(wgEncode.*Tfbs.*\.(?:narrow)|(?:broad)Peak.gz)</a>";
+    enum peakRegex = ctRegex!(peakRegexStr);
+    //note that the regex pattern itself is probably bogus
+    assert(match(r"\>wgEncode-blah-Tfbs.narrow</a>", peakRegex));
+}
+
+// bugzilla 9211
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto rx_1 =  regex(r"^(\w)*(\d)");
+    auto m = match("1234", rx_1);
+    assert(equal(m.front, ["1234", "3", "4"]));
+    auto rx_2 = regex(r"^([0-9])*(\d)");
+    auto m2 = match("1234", rx_2);
+    assert(equal(m2.front, ["1234", "3", "4"]));
+}
+
+// bugzilla 9280
+@safe unittest
+{
+    string tomatch = "a!b@c";
+    static r = regex(r"^(?P<nick>.*?)!(?P<ident>.*?)@(?P<host>.*?)$");
+    auto nm = match(tomatch, r);
+    assert(nm);
+    auto c = nm.captures;
+    assert(c[1] == "a");
+    assert(c["nick"] == "a");
+}
+
+
+// bugzilla 9579
+@safe unittest
+{
+    char[] input = ['a', 'b', 'c'];
+    string format = "($1)";
+    // used to give a compile error:
+    auto re = regex(`(a)`, "g");
+    auto r = replace(input, re, format);
+    assert(r == "(a)bc");
+}
+
+// bugzilla 9634
+@safe unittest
+{
+    auto re = ctRegex!"(?:a+)";
+    assert(match("aaaa", re).hit == "aaaa");
+}
+
+//bugzilla 10798
+@safe unittest
+{
+    auto cr = ctRegex!("[abcd--c]*");
+    auto m  = "abc".match(cr);
+    assert(m);
+    assert(m.hit == "ab");
+}
+
+// bugzilla 10913
+@system unittest
+{
+    @system static string foo(const(char)[] s)
+    {
+        return s.dup;
+    }
+    @safe static string bar(const(char)[] s)
+    {
+        return s.dup;
+    }
+    () @system {
+        replace!((a) => foo(a.hit))("blah", regex(`a`));
+    }();
+    () @safe {
+        replace!((a) => bar(a.hit))("blah", regex(`a`));
+    }();
+}
+
+// bugzilla 11262
+@safe unittest
+{
+    enum reg = ctRegex!(r",", "g");
+    auto str = "This,List";
+    str = str.replace(reg, "-");
+    assert(str == "This-List");
+}
+
+// bugzilla 11775
+@safe unittest
+{
+    assert(collectException(regex("a{1,0}")));
+}
+
+// bugzilla 11839
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    assert(regex(`(?P<var1>\w+)`).namedCaptures.equal(["var1"]));
+    assert(collectException(regex(`(?P<1>\w+)`)));
+    assert(regex(`(?P<v1>\w+)`).namedCaptures.equal(["v1"]));
+    assert(regex(`(?P<__>\w+)`).namedCaptures.equal(["__"]));
+    assert(regex(`(?P<я>\w+)`).namedCaptures.equal(["я"]));
+}
+
+// bugzilla 12076
+@safe unittest
+{
+    auto RE = ctRegex!(r"(?<!x[a-z]+)\s([a-z]+)");
+    string s = "one two";
+    auto m = match(s, RE);
+}
+
+// bugzilla 12105
+@safe unittest
+{
+    auto r = ctRegex!`.*?(?!a)`;
+    assert("aaab".matchFirst(r).hit == "aaa");
+    auto r2 = ctRegex!`.*(?!a)`;
+    assert("aaab".matchFirst(r2).hit == "aaab");
+}
+
+//bugzilla 11784
+@safe unittest
+{
+    assert("abcdefghijklmnopqrstuvwxyz"
+        .matchFirst("[a-z&&[^aeiuo]]").hit == "b");
+}
+
+//bugzilla 12366
+@safe unittest
+{
+     auto re = ctRegex!(`^((?=(xx+?)\2+$)((?=\2+$)(?=(x+)(\4+$))\5){2})*x?$`);
+     assert("xxxxxxxx".match(re).empty);
+     assert(!"xxxx".match(re).empty);
+}
+
+// bugzilla 12582
+@safe unittest
+{
+    auto r = regex(`(?P<a>abc)`);
+    assert(collectException("abc".matchFirst(r)["b"]));
+}
+
+// bugzilla 12691
+@safe unittest
+{
+    assert(bmatch("e@", "^([a-z]|)*$").empty);
+    assert(bmatch("e@", ctRegex!`^([a-z]|)*$`).empty);
+}
+
+//bugzilla  12713
+@safe unittest
+{
+    assertThrown(regex("[[a-z]([a-z]|(([[a-z])))"));
+}
+
+//bugzilla 12747
+@safe unittest
+{
+    assertThrown(regex(`^x(\1)`));
+    assertThrown(regex(`^(x(\1))`));
+    assertThrown(regex(`^((x)(?=\1))`));
+}
+
+// bugzilla 14504
+@safe unittest
+{
+    auto p = ctRegex!("a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?a?" ~
+            "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa");
+}
+
+// bugzilla 14529
+@safe unittest
+{
+    auto ctPat2 = regex(r"^[CDF]$", "i");
+    foreach (v; ["C", "c", "D", "d", "F", "f"])
+        assert(matchAll(v, ctPat2).front.hit == v);
+}
+
+// bugzilla 14615
+@safe unittest
+{
+    import std.array : appender;
+    import std.regex : replaceFirst, replaceFirstInto, regex;
+    import std.stdio : writeln;
+
+    auto example = "Hello, world!";
+    auto pattern = regex("^Hello, (bug)");  // won't find this one
+    auto result = replaceFirst(example, pattern, "$1 Sponge Bob");
+    assert(result == "Hello, world!");  // Ok.
+
+    auto sink = appender!string;
+    replaceFirstInto(sink, example, pattern, "$1 Sponge Bob");
+    assert(sink.data == "Hello, world!");
+    replaceAllInto(sink, example, pattern, "$1 Sponge Bob");
+    assert(sink.data == "Hello, world!Hello, world!");
+}
+
+// bugzilla 15573
+@safe unittest
+{
+    auto rx = regex("[c d]", "x");
+    assert("a b".matchFirst(rx));
+}
+
+// bugzilla 15864
+@safe unittest
+{
+    regex(`(<a (?:(?:\w+=\"[^"]*\")?\s*)*href="\.\.?)"`);
+}
+
+@safe unittest
+{
+    auto r = regex("(?# comment)abc(?# comment2)");
+    assert("abc".matchFirst(r));
+    assertThrown(regex("(?#..."));
+}
+
+// bugzilla 17075
+@safe unittest
+{
+    enum titlePattern = `<title>(.+)</title>`;
+    static titleRegex = ctRegex!titlePattern;
+    string input = "<title>" ~ "<".repeat(100_000).join;
+    assert(input.matchFirst(titleRegex).empty);
+}
+
+// bugzilla 17212
+@safe unittest
+{
+    auto r = regex(" [a] ", "x");
+    assert("a".matchFirst(r));
+}
+
+// bugzilla 17157
+@safe unittest
+{
+    import std.algorithm.comparison : equal;
+    auto ctr = ctRegex!"(a)|(b)|(c)|(d)";
+    auto r = regex("(a)|(b)|(c)|(d)", "g");
+    auto s = "--a--b--c--d--";
+    auto outcomes = [
+        ["a", "a", "", "", ""],
+        ["b", "", "b", "", ""],
+        ["c", "", "", "c", ""],
+        ["d", "", "", "", "d"]
+    ];
+    assert(equal!equal(s.matchAll(ctr), outcomes));
+    assert(equal!equal(s.bmatch(r), outcomes));
+}
+
+// bugzilla 17667
+@safe unittest
+{
+    import std.algorithm.searching : canFind;
+    void willThrow(T, size_t line = __LINE__)(T arg, string msg)
+    {
+        auto e = collectException(regex(arg));
+        assert(e.msg.canFind(msg), to!string(line) ~ ": " ~ e.msg);
+    }
+    willThrow([r".", r"[\(\{[\]\}\)]"], "no matching ']' found while parsing character class");
+    willThrow([r"[\", r"123"], "no matching ']' found while parsing character class");
+    willThrow([r"[a-", r"123"], "no matching ']' found while parsing character class");
+    willThrow([r"[a-\", r"123"], "invalid escape sequence");
+    willThrow([r"\", r"123"], "invalid escape sequence");
+}
+
+// bugzilla 17668
+@safe unittest
+{
+    import std.algorithm.searching;
+    auto e = collectException!RegexException(regex(q"<[^]>"));
+    assert(e.msg.canFind("no operand for '^'"));
+}
+
+// bugzilla 17673
+@safe unittest
+{
+    string str = `<">`;
+    string[] regexps = ["abc", "\"|x"];
+    auto regexp = regex(regexps);
+    auto c = matchFirst(str, regexp);
+    assert(c);
+    assert(c.whichPattern == 2);
+}
+
diff --git a/libphobos/src/std/socket.d b/libphobos/src/std/socket.d
index ecb2c8b..d7de153 100644
--- a/libphobos/src/std/socket.d
+++ b/libphobos/src/std/socket.d
@@ -85,10 +85,10 @@ else version (Posix)
         }
     }
 
+    public import core.sys.posix.netinet.in_;
     import core.sys.posix.arpa.inet;
     import core.sys.posix.fcntl;
     import core.sys.posix.netdb;
-    import core.sys.posix.netinet.in_;
     import core.sys.posix.netinet.tcp;
     import core.sys.posix.sys.select;
     import core.sys.posix.sys.socket;
diff --git a/libphobos/src/std/typecons.d b/libphobos/src/std/typecons.d
index a63227c..84e876f 100644
--- a/libphobos/src/std/typecons.d
+++ b/libphobos/src/std/typecons.d
@@ -4204,10 +4204,11 @@ package template OverloadSet(string nam, T...)
 /*
 Used by MemberFunctionGenerator.
  */
-package template FuncInfo(alias func, /+[BUG 4217 ?]+/ T = typeof(&func))
+package template FuncInfo(alias func)
+if (is(typeof(&func)))
 {
-    alias RT = ReturnType!T;
-    alias PT = Parameters!T;
+    alias RT = ReturnType!(typeof(&func));
+    alias PT = Parameters!(typeof(&func));
 }
 package template FuncInfo(Func)
 {
@@ -4248,6 +4249,7 @@ private static:
     // Internal stuffs
     //:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::://
     import std.format;
+    alias format = std.format.format;
 
     enum CONSTRUCTOR_NAME = "__ctor";
 
@@ -5024,7 +5026,7 @@ package template GetOverloadedMethods(T)
                     enum isMethod = false;
             }
             alias follows = AliasSeq!(
-                std.meta.Filter!(isMethod, __traits(getOverloads, T, name)),
+                Filter!(isMethod, __traits(getOverloads, T, name)),
                 follows!(i + 1));
         }
     }
@@ -5933,13 +5935,7 @@ mixin template Proxy(alias a)
             // built-in type field, manifest constant, and static non-mutable field
             enum opDispatch = mixin("a."~name);
         }
-        else static if (is(typeof(mixin("a."~name))) || __traits(getOverloads, a, name).length != 0)
-        {
-            // field or property function
-            @property auto ref opDispatch(this X)()                { return mixin("a."~name);        }
-            @property auto ref opDispatch(this X, V)(auto ref V v) { return mixin("a."~name~" = v"); }
-        }
-        else
+        else static if (__traits(isTemplate, mixin("a."~name)))
         {
             // member template
             template opDispatch(T...)
@@ -5948,6 +5944,13 @@ mixin template Proxy(alias a)
                 auto ref opDispatch(this X, Args...)(auto ref Args args){ return mixin("a."~name~targs~"(args)"); }
             }
         }
+        else
+        {
+            // field or property function
+            @property auto ref opDispatch(this X)()                { return mixin("a."~name);        }
+            @property auto ref opDispatch(this X, V)(auto ref V v) { return mixin("a."~name~" = v"); }
+        }
+
     }
 
     import std.traits : isArray;
diff --git a/libphobos/src/std/zip.d b/libphobos/src/std/zip.d
index 8b130ea..9e55d19 100644
--- a/libphobos/src/std/zip.d
+++ b/libphobos/src/std/zip.d
@@ -263,8 +263,8 @@ final class ArchiveMember
     {
     void print()
     {
-        printf("name = '%.*s'\n", name.length, name.ptr);
-        printf("\tcomment = '%.*s'\n", comment.length, comment.ptr);
+        printf("name = '%.*s'\n", cast(int) name.length, name.ptr);
+        printf("\tcomment = '%.*s'\n", cast(int) comment.length, comment.ptr);
         printf("\tmadeVersion = x%04x\n", _madeVersion);
         printf("\textractVersion = x%04x\n", extractVersion);
         printf("\tflags = x%04x\n", flags);
@@ -348,7 +348,7 @@ final class ZipArchive
         printf("\tdiskStartDir = %u\n", diskStartDir);
         printf("\tnumEntries = %u\n", numEntries);
         printf("\ttotalEntries = %u\n", totalEntries);
-        printf("\tcomment = '%.*s'\n", comment.length, comment.ptr);
+        printf("\tcomment = '%.*s'\n", cast(int) comment.length, comment.ptr);
     }
     }
 
diff --git a/libphobos/testsuite/Makefile.in b/libphobos/testsuite/Makefile.in
index c38a468..8855480 100644
--- a/libphobos/testsuite/Makefile.in
+++ b/libphobos/testsuite/Makefile.in
@@ -215,6 +215,7 @@ PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
 RANLIB = @RANLIB@
+SECTION_FLAGS = @SECTION_FLAGS@
 SED = @SED@
 SET_MAKE = @SET_MAKE@
 SHELL = @SHELL@
@@ -242,6 +243,8 @@ datadir = @datadir@
 datarootdir = @datarootdir@
 docdir = @docdir@
 dvidir = @dvidir@
+enable_shared = @enable_shared@
+enable_static = @enable_static@
 exec_prefix = @exec_prefix@
 gcc_version = @gcc_version@
 gdc_include_dir = @gdc_include_dir@
@@ -271,6 +274,7 @@ oldincludedir = @oldincludedir@
 pdfdir = @pdfdir@
 phobos_compiler_pic_flag = @phobos_compiler_pic_flag@
 phobos_compiler_shared_flag = @phobos_compiler_shared_flag@
+phobos_lt_pic_flag = @phobos_lt_pic_flag@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
diff --git a/libphobos/testsuite/libphobos.druntime/druntime.exp b/libphobos/testsuite/libphobos.druntime/druntime.exp
index 2f3a36f..daedfd7 100644
--- a/libphobos/testsuite/libphobos.druntime/druntime.exp
+++ b/libphobos/testsuite/libphobos.druntime/druntime.exp
@@ -15,7 +15,7 @@
 # <http://www.gnu.org/licenses/>.
 
 # Immediately exit if we can't run target executables.
-if { ![isnative] || ![is-effective-target static] } {
+if { ![isnative] } {
     return
 }
 
@@ -34,7 +34,8 @@ dg-init
 # Main loop.
 foreach test $tests {
     set libphobos_test_name "$subdir/[dg-trim-dirname $srcdir/../libdruntime $test]"
-    dg-runtest $test "" "-fmain -fbuilding-libphobos-tests $version_flags"
+    dg-runtest $test "-static-libphobos" \
+	"-fmain -fbuilding-libphobos-tests $version_flags"
     set libphobos_test_name ""
 }
 
diff --git a/libphobos/testsuite/libphobos.druntime_shared/druntime_shared.exp b/libphobos/testsuite/libphobos.druntime_shared/druntime_shared.exp
index 6ca62a3..51f9c2c 100644
--- a/libphobos/testsuite/libphobos.druntime_shared/druntime_shared.exp
+++ b/libphobos/testsuite/libphobos.druntime_shared/druntime_shared.exp
@@ -34,7 +34,7 @@ dg-init
 # Main loop.
 foreach test $tests {
     set libphobos_test_name "$subdir/[dg-trim-dirname $srcdir/../libdruntime $test]"
-    dg-runtest $test "-fversion=Shared -shared-libphobos" \
+    dg-runtest $test "-shared-libphobos" \
 	"-fmain -fbuilding-libphobos-tests -fno-moduleinfo $version_flags"
     set libphobos_test_name ""
 }
diff --git a/libphobos/testsuite/libphobos.exceptions/chain.d b/libphobos/testsuite/libphobos.exceptions/chain.d
index 462ba24..0305707 100644
--- a/libphobos/testsuite/libphobos.exceptions/chain.d
+++ b/libphobos/testsuite/libphobos.exceptions/chain.d
@@ -65,14 +65,14 @@ void main()
         string prefix = "";
         for ({ size_t i; Throwable ex = original; } ex; ex = ex.next, ++i)
         {
-            printf("%.*s%.*s\n", prefix.length, prefix.ptr, ex.msg.length, ex.msg.ptr);
+            printf("%.*s%.*s\n", cast(int)prefix.length, prefix.ptr, cast(int)ex.msg.length, ex.msg.ptr);
             prefix = prefix~" ";
         }
         printf("Bypassed chain was:\n");
         prefix = "";
         for ({ size_t i; Throwable ex = original.bypassedException; } ex; ex = ex.next, ++i)
         {
-            printf("%.*s%.*s\n", prefix.length, prefix.ptr, ex.msg.length, ex.msg.ptr);
+            printf("%.*s%.*s\n", cast(int)prefix.length, prefix.ptr, cast(int)ex.msg.length, ex.msg.ptr);
             prefix = prefix~" ";
         }
     }
diff --git a/libphobos/testsuite/libphobos.exceptions/line_trace.d b/libphobos/testsuite/libphobos.exceptions/line_trace.d
index 7b75d3a..70762ff 100644
--- a/libphobos/testsuite/libphobos.exceptions/line_trace.d
+++ b/libphobos/testsuite/libphobos.exceptions/line_trace.d
@@ -9,7 +9,7 @@ void main()
     {
         import core.stdc.stdio;
         auto str = e.toString();
-        printf("%.*s\n", str.length, str.ptr);
+        printf("%.*s\n", cast(int)str.length, str.ptr);
     }
 }
 
diff --git a/libphobos/testsuite/libphobos.phobos/phobos.exp b/libphobos/testsuite/libphobos.phobos/phobos.exp
index 0975ab1..937849e 100644
--- a/libphobos/testsuite/libphobos.phobos/phobos.exp
+++ b/libphobos/testsuite/libphobos.phobos/phobos.exp
@@ -15,7 +15,7 @@
 # <http://www.gnu.org/licenses/>.
 
 # Immediately exit if we can't run target executables.
-if { ![isnative] || ![is-effective-target static] } {
+if { ![isnative] } {
     return
 }
 
@@ -45,7 +45,8 @@ dg-init
 # Main loop.
 foreach test $tests {
     set libphobos_test_name "$subdir/[dg-trim-dirname $srcdir/../src $test]"
-    dg-runtest $test "" "-fmain -fbuilding-libphobos-tests $version_flags"
+    dg-runtest $test "-static-libphobos" \
+	"-fmain -fbuilding-libphobos-tests $version_flags"
     set libphobos_test_name ""
 }
 
diff --git a/libphobos/testsuite/libphobos.phobos_shared/phobos_shared.exp b/libphobos/testsuite/libphobos.phobos_shared/phobos_shared.exp
index da31304..8498522 100644
--- a/libphobos/testsuite/libphobos.phobos_shared/phobos_shared.exp
+++ b/libphobos/testsuite/libphobos.phobos_shared/phobos_shared.exp
@@ -45,7 +45,7 @@ dg-init
 # Main loop.
 foreach test $tests {
     set libphobos_test_name "$subdir/[dg-trim-dirname $srcdir/../src $test]"
-    dg-runtest $test "-fversion=Shared -shared-libphobos" \
+    dg-runtest $test "-shared-libphobos" \
 	"-fmain -fbuilding-libphobos-tests -fno-moduleinfo $version_flags"
     set libphobos_test_name ""
 }
diff --git a/libphobos/testsuite/libphobos.thread/fiber_guard_page.d b/libphobos/testsuite/libphobos.thread/fiber_guard_page.d
index 9f754e1..ca54a19 100644
--- a/libphobos/testsuite/libphobos.thread/fiber_guard_page.d
+++ b/libphobos/testsuite/libphobos.thread/fiber_guard_page.d
@@ -1,13 +1,15 @@
 // { dg-options "-O0" }
 // { dg-shouldfail "segv or bus error" }
 import core.thread;
+import core.sys.posix.signal;
 import core.sys.posix.sys.mman;
 
 // this should be true for most architectures
 // (taken from core.thread)
-version = StackGrowsDown;
+version (GNU_StackGrowsDown)
+    version = StackGrowsDown;
 
-enum stackSize = 4096;
+enum stackSize = MINSIGSTKSZ;
 
 // Simple method that causes a stack overflow
 void stackMethod()
diff --git a/libphobos/testsuite/testsuite_flags.in b/libphobos/testsuite/testsuite_flags.in
index 6a2d79f..bafd5ad4 100755
--- a/libphobos/testsuite/testsuite_flags.in
+++ b/libphobos/testsuite/testsuite_flags.in
@@ -28,7 +28,8 @@ case ${query} in
       ;;
     --gdcflags)
       GDCFLAGS_default="-fmessage-length=0 -fno-show-column"
-      GDCFLAGS_config="@WARN_DFLAGS@ @GDCFLAGS@ @CET_DFLAGS@ -fno-release -funittest"
+      GDCFLAGS_config="@WARN_DFLAGS@ @GDCFLAGS@ @CET_DFLAGS@
+		       @phobos_compiler_shared_flag@ -fno-release -funittest"
       echo ${GDCFLAGS_default} ${GDCFLAGS_config}
       ;;
     --gdcpaths)