[Bug sanitizer/55519] New: [asan] False positive -Wmaybe-uninitialized

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55519

             Bug #: 55519
           Summary: [asan] False positive -Wmaybe-uninitialized
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: hjl.to...@gmail.com
                CC: do...@gcc.gnu.org, dvyu...@gcc.gnu.org,
                    ja...@gcc.gnu.org, k...@gcc.gnu.org


When -fsanitize=address is used with -O2 -flto=jobserver -frandom-seed=1,
I got

/export/gnu/import/git/gcc/gcc/tree-ssa-loop-im.c: In function
‘store_motion_loop(loop*, bitmap_head_def*)’:
/export/gnu/import/git/gcc/gcc/tree-ssa-loop-im.c:2014:29: warning:
‘store_flag’ may be used uninitialized in this function [-Wmaybe-uninitialized]
        NULL_TREE, NULL_TREE);
                             ^
/export/gnu/import/git/gcc/gcc/tree-ssa-loop-im.c:2113:17: note: ‘store_flag’
was declared here
   tree tmp_var, store_flag;

/export/gnu/import/git/gcc/gcc/gcc.c: In function ‘do_spec_1(char const*, int,
char const*)’:
/export/gnu/import/git/gcc/gcc/../include/obstack.h:337:52: warning:
‘save_growing_value’ may be used uninitialized in this function
[-Wmaybe-uninitialized]
    _obstack_memcpy (__o->next_free, (where), __len);   \
                                                    ^
/export/gnu/import/git/gcc/gcc/gcc.c:5489:9: note: ‘save_growing_value’ was
declared here
   void *save_growing_value;