https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106115
Bug ID: 106115
Summary: wrong code at -O2 and -O3 on x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: zhendong.su at inf dot ethz.ch
Target Milestone: ---
Another recent regression from 12.*.
It might be related to PR 106114.
[547] % gcctk -v
Using built-in specs.
COLLECT_GCC=gcctk
COLLECT_LTO_WRAPPER=/local/suz-local/software/local/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/13.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--prefix=/local/suz-local/software/local/gcc-trunk --enable-sanitizers
--enable-languages=c,c++ --disable-werror --enable-multilib --with-system-zlib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 13.0.0 20220628 (experimental) [master r13-1313-gf9764ea128c] (GCC)
[548] %
[548] % gcctk -O1 small.c; ./a.out
[549] %
[549] % gcctk -O2 small.c
[550] % ./a.out
65535
[551] %
[551] % cat small.c
int printf(const char *, ...);
int a, b = 1041281974;
unsigned short c;
int main()
{
int d, e = b;
b = ~-~a;
a = c = -~b;
if (c < 65529) {
printf("%d\n", d);
e = 0;
}
if (b)
d = a;
if (((e > 1041281974) && d) || e < 1041281974)
printf("%d\n", c);
return 0;
}