https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93100
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Known to fail| |10.2.1, 11.0, 9.3.0
CC| |msebor at gcc dot gnu.org
Component|sanitizer |middle-end
Last reconfirmed|2020-01-09 00:00:00 |2021-4-16
Status|NEW |ASSIGNED
Depends on| |98508
Assignee|unassigned at gcc dot gnu.org |msebor at gcc dot
gnu.org
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> ---
Reconfirming with GCC 11. The reason for the false negative is that
instrumentation functions injected by the sanitizers look to the warning like
they might initialize the variables. That's simply because the warning hasn't
been taught they're special and don't write to the variables. The patch in
pr98508 comment 5 enables the warning. Let me submit it for GCC 12.
void f ()
{
struct A b;
struct A a;
int _1;
<bb 2> :
# .MEM_4 = VDEF <.MEM_3(D)>
.ASAN_MARK (UNPOISON, &a, 8); <<< assumed to write to a
# VUSE <.MEM_4>
_1 = a.i; <<< missing warning
if (_1 != 0)
goto <bb 3>; [INV]
else
goto <bb 4>; [INV]
<bb 3> :
# .MEM_5 = VDEF <.MEM_4>
b = a;
<bb 4> :
# .MEM_2 = PHI <.MEM_4(2), .MEM_5(3)>
# .MEM_6 = VDEF <.MEM_2>
.ASAN_MARK (POISON, &a, 8);
# VUSE <.MEM_6>
return;
}
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98508
[Bug 98508] Sanitizer disable -Wall and -Wextra
