diff options
author | H.J. Lu <hjl.tools@gmail.com> | 2017-10-15 08:16:26 -0700 |
---|---|---|
committer | H.J. Lu <hjl.tools@gmail.com> | 2017-10-15 08:16:37 -0700 |
commit | 8e57c9432a2b68c8a1e7f4df28f0e8c7acc04753 (patch) | |
tree | 6dd8b1f6f37eba37693ca86d946db379394619a5 /malloc/hooks.c | |
parent | a4777c46af89649f2282c1703e8117ccd058d719 (diff) | |
download | glibc-8e57c9432a2b68c8a1e7f4df28f0e8c7acc04753.tar.gz glibc-8e57c9432a2b68c8a1e7f4df28f0e8c7acc04753.tar.xz glibc-8e57c9432a2b68c8a1e7f4df28f0e8c7acc04753.zip |
Silence -O3 -Wall warning in malloc/hooks.c with GCC 7 [BZ #22052]
realloc_check has unsigned char *magic_p; ... __libc_lock_lock (main_arena.mutex); const mchunkptr oldp = mem2chunk_check (oldmem, &magic_p); __libc_lock_unlock (main_arena.mutex); if (!oldp) malloc_printerr ("realloc(): invalid pointer"); ... if (newmem == NULL) *magic_p ^= 0xFF; with static void malloc_printerr(const char *str) __attribute__ ((noreturn)); GCC 7 -O3 warns hooks.c: In function ‘realloc_check’: hooks.c:352:14: error: ‘magic_p’ may be used uninitialized in this function [-Werror=maybe-uninitialized] *magic_p ^= 0xFF; due to the GCC bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82090 This patch silences GCC 7 by using DIAG_IGNORE_NEEDS_COMMENT. [BZ #22052] * malloc/hooks.c (realloc_check): Use DIAG_IGNORE_NEEDS_COMMENT to silence -O3 -Wall warning with GCC 7.
Diffstat (limited to 'malloc/hooks.c')
-rw-r--r-- | malloc/hooks.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/malloc/hooks.c b/malloc/hooks.c index 01be076f5e..17d8907727 100644 --- a/malloc/hooks.c +++ b/malloc/hooks.c @@ -345,11 +345,18 @@ realloc_check (void *oldmem, size_t bytes, const void *caller) newmem = _int_realloc (&main_arena, oldp, oldsize, nb); } + DIAG_PUSH_NEEDS_COMMENT; +#if __GNUC_PREREQ (7, 0) + /* GCC 7 warns about magic_p may be used uninitialized. But we never + reach here if magic_p is uninitialized. */ + DIAG_IGNORE_NEEDS_COMMENT (7, "-Wmaybe-uninitialized"); +#endif /* mem2chunk_check changed the magic byte in the old chunk. If newmem is NULL, then the old chunk will still be used though, so we need to invert that change here. */ if (newmem == NULL) *magic_p ^= 0xFF; + DIAG_POP_NEEDS_COMMENT; __libc_lock_unlock (main_arena.mutex); |