https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111383
Bug ID: 111383
Summary: Wrong code at -Os on x86_64-linux-gnu since
r12-5138-ge82c382971
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: shaohua.li at inf dot ethz.ch
CC: aldyh at redhat dot com
Target Milestone: ---
gcc at -Os produced the wrong code.
Bisected to r12-5138-ge82c382971
Compiler explorer: https://godbolt.org/z/eYY31rn4d
$ cat a.c
int printf(const char *, ...);
int a, d = 1625015426;
char e;
short b;
short *f = &b, *g = &b;
void h(char *k) {
char c = *k;
for (; c;)
;
}
int main() {
*g = 25330;
int i, j;
i = 0;
for (; *f + d - 1625040257 < 7;)
;
for (; i < 4; i++) {
j = 0;
for (; (d - 1625015511) + (d - 1625015341) + j < 1; j++)
h(&e);
}
printf("%d\n", a);
}
$
$ gcc -O0 a.c && ./a.out
0
$ gcc -Os a.c && ./a.out
(Timeout)
$
$ gcc -fsanitize=address,undefined a.c && ./a.out
0
$
