elf: Silence GCC 11/12 false positive warning

Silence GCC 11/12 false positive warning with -mavx512f on dl-load.c:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106008

$ gcc -O2 -fPIC -march=x86-64 -mavx512f -S -Wall ...
dl-load.c: In function ‘_dl_map_object_from_fd.constprop’:
dl-load.c:1158:30: warning: ‘(((char *)loadcmds.113_68 + _933 + 16))[329406144173384849].mapend’ may be used uninitialized [-Wmaybe-uninitialized]
This commit is contained in:
H.J. Lu 2022-06-16 18:52:02 -07:00
parent c22eb807b0
commit 33ead02758

View File

@ -1152,10 +1152,20 @@ _dl_map_object_from_fd (const char *name, const char *origname, int fd,
p_align_max = ph->p_align;
c->mapoff = ALIGN_DOWN (ph->p_offset, GLRO(dl_pagesize));
DIAG_PUSH_NEEDS_COMMENT;
#if __GNUC_PREREQ (11, 0)
/* Suppress invalid GCC warning:
(((char *)loadcmds.113_68 + _933 + 16))[329406144173384849].mapend may be used uninitialized [-Wmaybe-uninitialized]
See: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106008
*/
DIAG_IGNORE_NEEDS_COMMENT (11, "-Wmaybe-uninitialized");
#endif
/* Determine whether there is a gap between the last segment
and this one. */
if (nloadcmds > 1 && c[-1].mapend != c->mapstart)
has_holes = true;
DIAG_POP_NEEDS_COMMENT;
/* Optimize a common case. */
#if (PF_R | PF_W | PF_X) == 7 && (PROT_READ | PROT_WRITE | PROT_EXEC) == 7