libcc1: Enable Intel CET on Intel CET enabled host

Since on Intel CET enabled host, dlopen in Intel CET enabled applications
fails on shared libraries which aren't Intel CET enabled, enable Intel
CET in libcc1 on Intel CET enabled host.

	* Makefile.am (AM_CXXFLAGS): Add $(CET_HOST_FLAGS).
	* configure.ac: Add GCC_CET_HOST_FLAGS(CET_HOST_FLAGS) and
	AC_SUBST(CET_HOST_FLAGS).
	* Makefile.in: Regenerated.
	* aclocal.m4: Likewise.
	* configure: Likewise.

1 files changed, 147 insertions, 2 deletions

diff --git a/libcc1/configure b/libcc1/configure
index 64fdc44..76377a2 100755
--- a/libcc1/configure
+++ b/libcc1/configure
@@ -642,6 +642,7 @@ WARN_FLAGS
 CONFIG_STATUS_DEPENDENCIES
 gcc_version
 get_gcc_base_ver
+CET_HOST_FLAGS
 visibility
 CXXCPP
 am__fastdepCXX_FALSE
@@ -784,6 +785,7 @@ with_pic
 enable_fast_install
 with_gnu_ld
 enable_libtool_lock
+enable_cet
 with_gcc_major_version_only
 enable_werror_always
 enable_plugin
@@ -1435,6 +1437,7 @@ Optional Features:
   --enable-fast-install[=PKGS]
                           optimize for fast installation [default=yes]
   --disable-libtool-lock  avoid locking (might break parallel builds)
+  --enable-cet            enable Intel CET in host libraries [default=auto]
   --enable-werror-always  enable -Werror despite compiler version
   --enable-plugin         enable plugin support
 
@@ -10780,7 +10783,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10783 "configure"
+#line 10786 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -10886,7 +10889,7 @@ else
   lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
   lt_status=$lt_dlunknown
   cat > conftest.$ac_ext <<_LT_EOF
-#line 10889 "configure"
+#line 10892 "configure"
 #include "confdefs.h"
 
 #if HAVE_DLFCN_H
@@ -14538,6 +14541,148 @@ if test "$GXX" = yes; then
 fi
 
 
+ # Check whether --enable-cet was given.
+if test "${enable_cet+set}" = set; then :
+  enableval=$enable_cet;
+      case "$enableval" in
+       yes|no|auto) ;;
+       *) as_fn_error $? "Unknown argument to enable/disable cet" "$LINENO" 5 ;;
+                          esac
+
+else
+  enable_cet=auto
+fi
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for CET support" >&5
+$as_echo_n "checking for CET support... " >&6; }
+
+case "$host" in
+  i[34567]86-*-linux* | x86_64-*-linux*)
+    may_have_cet=yes
+    save_CFLAGS="$CFLAGS"
+    CFLAGS="$CFLAGS -fcf-protection"
+    case "$enable_cet" in
+      auto)
+	# Check if target supports multi-byte NOPs
+	# and if assembler supports CET insn.
+	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+
+#if !defined(__SSE2__)
+#error target does not support multi-byte NOPs
+#else
+asm ("setssbsy");
+#endif
+
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  enable_cet=yes
+else
+  enable_cet=no
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+	;;
+      yes)
+	# Check if assembler supports CET.
+	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+int
+main ()
+{
+asm ("setssbsy");
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+
+else
+  as_fn_error $? "assembler with CET support is required for --enable-cet" "$LINENO" 5
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+	;;
+    esac
+    CFLAGS="$save_CFLAGS"
+    ;;
+  *)
+    may_have_cet=no
+    enable_cet=no
+    ;;
+esac
+
+if test x$may_have_cet = xyes; then
+  save_LDFLAGS="$LDFLAGS"
+  LDFLAGS="$LDFLAGS -Wl,-z,ibt,-z,shstk"
+  if test "$cross_compiling" = yes; then :
+  { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
+$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
+as_fn_error $? "cannot run test program while cross compiling
+See \`config.log' for more details" "$LINENO" 5; }
+else
+  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+static void
+foo (void)
+{
+}
+
+static void
+__attribute__ ((noinline, noclone))
+xxx (void (*f) (void))
+{
+  f ();
+}
+
+static void
+__attribute__ ((noinline, noclone))
+bar (void)
+{
+  xxx (foo);
+}
+
+int
+main ()
+{
+  bar ();
+  return 0;
+}
+
+_ACEOF
+if ac_fn_c_try_run "$LINENO"; then :
+  have_cet=no
+else
+  have_cet=yes
+fi
+rm -f core *.core core.conftest.* gmon.out bb.out conftest$ac_exeext \
+  conftest.$ac_objext conftest.beam conftest.$ac_ext
+fi
+
+  LDFLAGS="$save_LDFLAGS"
+  if test x$enable_cet = xno -a x$have_cet = xyes; then
+    as_fn_error $? "Intel CET must be enabled on Intel CET enabled host" "$LINENO" 5
+  fi
+fi
+if test x$enable_cet = xyes; then
+  CET_HOST_FLAGS="-fcf-protection"
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+else
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+
 ac_fn_c_check_decl "$LINENO" "basename" "ac_cv_have_decl_basename" "$ac_includes_default"
 if test "x$ac_cv_have_decl_basename" = xyes; then :
   ac_have_decl=1