libstdc++: Make _GLIBCXX_HOSTED respect -ffreestanding [PR103626]

This allows the library to switch to freestanding mode when compiling
with the -ffreestanding flag. This means you don't need a separate
libstdc++ build configured with --disable-hosted-libstdcxx in order to
compile for a freestanding environment.

The testsuite support files cannot be compiled for freestanding, so add
-fno-freestanding to override any -ffreestanding in the test flags.

libstdc++-v3/ChangeLog:

	PR libstdc++/103626
	* acinclude.m4 (GLIBCXX_ENABLE_HOSTED): Define _GLIBCXX_HOSTED
	to __STDC_HOSTED__ for non-freestanding installations.
	* configure: Regenerate.
	* include/Makefile.am (${host_builddir}/c++config.h): Adjust
	grep pattern.
	* include/Makefile.in: Regenerate.
	* testsuite/lib/libstdc++.exp (v3-build_support): Use
	-fno-freestanding.
	* testsuite/libstdc++-abi/abi.exp: Likewise.

6 files changed, 7 insertions, 7 deletions

diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4
index 9aa81e1..1b404d7 100644
--- a/libstdc++-v3/acinclude.m4
+++ b/libstdc++-v3/acinclude.m4
@@ -2992,7 +2992,7 @@ AC_DEFUN([GLIBCXX_ENABLE_HOSTED], [
     fi
   else
     is_hosted=yes
-    hosted_define=1
+    hosted_define=__STDC_HOSTED__
   fi
   GLIBCXX_CONDITIONAL(GLIBCXX_HOSTED, test $is_hosted = yes)
   AC_DEFINE_UNQUOTED(_GLIBCXX_HOSTED, $hosted_define,
diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure
index 07916d1..1ff28af 100755
--- a/libstdc++-v3/configure
+++ b/libstdc++-v3/configure
@@ -15651,7 +15651,7 @@ $as_echo "$as_me: Only freestanding libraries will be built" >&6;}
     fi
   else
     is_hosted=yes
-    hosted_define=1
+    hosted_define=__STDC_HOSTED__
   fi
 
 
diff --git a/libstdc++-v3/include/Makefile.am b/libstdc++-v3/include/Makefile.am
index 3eeb407..3472e84 100644
--- a/libstdc++-v3/include/Makefile.am
+++ b/libstdc++-v3/include/Makefile.am
@@ -1326,7 +1326,7 @@ ${host_builddir}/c++config.h: ${CONFIG_HEADER} \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
 	&& ldbl_alt128_compat='s,^#undef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT$$,#define _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT 1,' ;\
 	verbose_assert='s,g,g,' ; \
-	grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_HOSTED[	 ][	 ]*1[	 ]*$$" \
+	grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_HOSTED[	 ][	 ]*__STDC_HOSTED__[	 ]*$$" \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
 	&& grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_VERBOSE[	 ][	 ]*1[	 ]*$$" \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
diff --git a/libstdc++-v3/include/Makefile.in b/libstdc++-v3/include/Makefile.in
index e24563c..39ef34f 100644
--- a/libstdc++-v3/include/Makefile.in
+++ b/libstdc++-v3/include/Makefile.in
@@ -1820,7 +1820,7 @@ ${host_builddir}/c++config.h: ${CONFIG_HEADER} \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
 	&& ldbl_alt128_compat='s,^#undef _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT$$,#define _GLIBCXX_LONG_DOUBLE_ALT128_COMPAT 1,' ;\
 	verbose_assert='s,g,g,' ; \
-	grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_HOSTED[	 ][	 ]*1[	 ]*$$" \
+	grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_HOSTED[	 ][	 ]*__STDC_HOSTED__[	 ]*$$" \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
 	&& grep "^[	 ]*#[	 ]*define[	 ][	 ]*_GLIBCXX_VERBOSE[	 ][	 ]*1[	 ]*$$" \
 	${CONFIG_HEADER} > /dev/null 2>&1 \
diff --git a/libstdc++-v3/testsuite/lib/libstdc++.exp b/libstdc++-v3/testsuite/lib/libstdc++.exp
index 0338b50..d3256b6 100644
--- a/libstdc++-v3/testsuite/lib/libstdc++.exp
+++ b/libstdc++-v3/testsuite/lib/libstdc++.exp
@@ -654,7 +654,7 @@ proc v3-build_support { } {
 	# do not prevent compilation.
 	# Disable LTO so that ar/ranlib don't need the LTO plugin.
 	if { [v3_target_compile $srcdir/util/$f $object_file "object" \
-		  [list "incdir=$srcdir" "additional_flags=-w -fno-lto"]]
+		  [list "incdir=$srcdir" "additional_flags=-w -fno-lto -fno-freestanding"]]
 	     != "" } {
 	    error "could not compile $f"
 	}
@@ -693,7 +693,7 @@ proc v3-build_support { } {
 	    # Compile with "-w" so that warnings issued by the compiler
 	    # do not prevent compilation.
 	    if { [v3_target_compile $srcdir/util/$f $object_file "sharedlib" \
-	     [list "incdir=$srcdir" "additional_flags=-fno-inline -w -shared -fPIC -DPIC -std=gnu++98"]]
+	     [list "incdir=$srcdir" "additional_flags=-fno-inline -w -shared -fPIC -DPIC -std=gnu++98 -fno-freestanding"]]
 		 != "" } {
 		error "could not compile $f"
 	    }
diff --git a/libstdc++-v3/testsuite/libstdc++-abi/abi.exp b/libstdc++-v3/testsuite/libstdc++-abi/abi.exp
index 9e919e1..66f19ea 100644
--- a/libstdc++-v3/testsuite/libstdc++-abi/abi.exp
+++ b/libstdc++-v3/testsuite/libstdc++-abi/abi.exp
@@ -60,7 +60,7 @@ remote_exec "build" "$blddir/scripts/extract_symvers" \
 
 # Build the abi_check program.
 if { [v3_target_compile "$srcdir/util/testsuite_abi_check.cc" "abi_check" \
-      "executable" [list "additional_flags=-w"]] != "" } {
+      "executable" [list "additional_flags=-w -fno-freestanding"]] != "" } {
     error "could not compile testsuite_abi_check.cc"
 }