Do not stack-protect ifunc resolvers [BZ #7065]

When dynamically linking, ifunc resolvers are called before TLS is
initialized, so they cannot be safely stack-protected.

We avoid disabling stack-protection on large numbers of files by
using __attribute__ ((__optimize__ ("-fno-stack-protector")))
to turn it off just for the resolvers themselves.  (We provide
the attribute even when statically linking, because we will later
use it elsewhere too.)

1 files changed, 2 insertions, 0 deletions

diff --git a/configure b/configure
index 8c69f09232..b3007953ea 100755
--- a/configure
+++ b/configure
@@ -3994,6 +3994,8 @@ stack_protector=
 no_stack_protector=
 if test "$libc_cv_ssp" = yes; then
   no_stack_protector="-fno-stack-protector -DSTACK_PROTECTOR_LEVEL=0"
+  $as_echo "#define HAVE_CC_NO_STACK_PROTECTOR 1" >>confdefs.h
+
 fi
 
 if test "$enable_stack_protector" = yes && test "$libc_cv_ssp" = yes; then