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]

diff --git a/elf/dl-load.c b/elf/dl-load.c
index 2e4a010..1ad0868 100644 (file)
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -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