[glibc/release/2.34/master] Enable _FORTIFY_SOURCE=3 for gcc 12 and above

[glibc/release/2.34/master] Enable _FORTIFY_SOURCE=3 for gcc 12 and above

[Siddhesh Poyarekar]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=d6a58bd81d07322ff5da8f419d8620ef037b6a36

commit d6a58bd81d07322ff5da8f419d8620ef037b6a36
Author: Siddhesh Poyarekar <siddhesh@sourceware.org>
Date:   Wed Jan 12 18:46:28 2022 +0530

    Enable _FORTIFY_SOURCE=3 for gcc 12 and above
    
    gcc 12 now has support for the __builtin_dynamic_object_size builtin.
    Adapt the macro checks to enable _FORTIFY_SOURCE=3 on gcc 12 and above.
    
    Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
    Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
    (cherry picked from commit 86bf0feb0e3ec8e37872f72499d6ae33406561d7)

Diff:
---
 include/features.h | 4 +++-
 misc/sys/cdefs.h   | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/features.h b/include/features.h
index d974eabfaf..933499bcff 100644
--- a/include/features.h
+++ b/include/features.h
@@ -412,7 +412,9 @@
 #  warning _FORTIFY_SOURCE requires compiling with optimization (-O)
 # elif !__GNUC_PREREQ (4, 1)
 #  warning _FORTIFY_SOURCE requires GCC 4.1 or later
-# elif _FORTIFY_SOURCE > 2 && __glibc_clang_prereq (9, 0)
+# elif _FORTIFY_SOURCE > 2 && (__glibc_clang_prereq (9, 0)		      \
+			       || __GNUC_PREREQ (12, 0))
+
 #  if _FORTIFY_SOURCE > 3
 #   warning _FORTIFY_SOURCE > 3 is treated like 3 on this platform
 #  endif
diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index 3bb9f38916..515fb681a0 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -142,7 +142,8 @@
 #define __bos0(ptr) __builtin_object_size (ptr, 0)
 
 /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available.  */
-#if __USE_FORTIFY_LEVEL == 3 && __glibc_clang_prereq (9, 0)
+#if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0)		      \
+				 || __GNUC_PREREQ (12, 0))
 # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0)
 # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1)
 #else