https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111839
Bug ID: 111839
Summary: Wrong code at -O3 on x86_64-linux-gnu since
r12-2097-g9f34b780b0
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Keywords: wrong-code
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: shaohua.li at inf dot ethz.ch
CC: rguenth at gcc dot gnu.org
Target Milestone: ---
gcc at -O3 produced the wrong code.
Bisected to r12-2097-g9f34b780b0
Compiler explorer: https://godbolt.org/z/Ea1hGGnob
$ cat a.c
int printf(const char *, ...);
long a;
int b, c, e, g, i;
long *d, *h;
char f = -26;
int main() {
long j;
c = 0;
for (; c != 7; ++c) {
long k=0;
long l = k;
long **m = &d;
for (; f + i!=0; i++)
h = &l;
g = h != (*m = &j);
int *n = &b;
*n = g;
for (; e;)
for (; a; a = a + 1)
;
}
printf("%d\n", b);
}
$
$ gcc -fsanitize=address,undefined a.c && ./a.out
1
$ gcc -O3 a.c && ./a.out
0
$
