From 56e00c585420af63fc4df9e28ff9e12bb2a3274f Mon Sep 17 00:00:00 2001
From: Siddhesh Poyarekar <siddhesh@sourceware.org>
Date: Thu, 2 Feb 2023 07:49:02 -0500
Subject: [PATCH 184/185] cdefs: Limit definition of fortification macros
Define the __glibc_fortify and other macros only when __FORTIFY_LEVEL >
0. This has the effect of not defining these macros on older C90
compilers that do not have support for variable length argument lists.
Also trim off the trailing backslashes from the definition of
__glibc_fortify and __glibc_fortify_n macros.
Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit 2337e04e21ba6040926ec871e403533f77043c40)
---
misc/sys/cdefs.h | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/misc/sys/cdefs.h b/misc/sys/cdefs.h
index f525f67547f0..294e63333599 100644
--- a/misc/sys/cdefs.h
+++ b/misc/sys/cdefs.h
@@ -152,6 +152,7 @@
# define __glibc_objsize(__o) __bos (__o)
#endif
+#if __USE_FORTIFY_LEVEL > 0
/* Compile time conditions to choose between the regular, _chk and _chk_warn
variants. These conditions should get evaluated to constant and optimized
away. */
@@ -187,7 +188,7 @@
? __ ## f ## _alias (__VA_ARGS__) \
: (__glibc_unsafe_len (__l, __s, __osz) \
? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \
- : __ ## f ## _chk (__VA_ARGS__, __osz))) \
+ : __ ## f ## _chk (__VA_ARGS__, __osz)))
/* Fortify function f, where object size argument passed to f is the number of
elements and not total size. */
@@ -197,7 +198,8 @@
? __ ## f ## _alias (__VA_ARGS__) \
: (__glibc_unsafe_len (__l, __s, __osz) \
? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \
- : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) \
+ : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s))))
+#endif
#if __GNUC_PREREQ (4,3)
# define __warnattr(msg) __attribute__((__warning__ (msg)))
--
2.39.1
