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>
This commit is contained in:
Siddhesh Poyarekar 2023-02-02 07:49:02 -05:00
parent e0dc827bf6
commit 2337e04e21

View File

@ -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)))