https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111583
Bug ID: 111583
Summary: [13/14 Regression] Wrong code at -Os on
x86_64-linux-gnu since r13-3281-g6cc3394507
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: amacleod at redhat dot com
Target Milestone: ---
gcc at -Os produced the wrong code.
Bisected to r13-3281-g6cc3394507
Compiler explorer: https://godbolt.org/z/8GM9YvMKb
$ cat a.c
int printf(const char *, ...);
int b, c, d;
char e;
short f;
const unsigned short **g;
char h(char k) {
if (k)
return '0';
return 0;
}
int l() {
b = 0;
return 1;
}
static short m(unsigned k) {
const unsigned short *n[65];
g = &n[4];
k || l();
long a = k;
char i = 0;
unsigned long j = k;
while (j--)
*(char *)a++ = i;
c = h(d);
f = k;
return 0;
}
int main() {
long o = (e < 0) << 5;
m(o);
printf("%d\n", f);
}
$
$ gcc -O0 -fsanitize=address,undefined a.c && ./a.out
0
$ gcc -Os a.c && ./a.out
32
$
