https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115701
Bug ID: 115701
Summary: wrong code at -O1 and above with "-fipa-pta" on
x86_64-linux-gnu
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: ipa
Assignee: unassigned at gcc dot gnu.org
Reporter: zhendong.su at inf dot ethz.ch
Target Milestone: ---
It appears to be a regression from 9.*, and affects 10.* and later.
Compiler Explorer: https://godbolt.org/z/szxjKcz8b
[537] % 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/15.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: ../gcc-trunk/configure --disable-bootstrap
--enable-checking=yes --prefix=/local/suz-local/software/local/gcc-trunk
--enable-sanitizers --enable-languages=c,c++ --disable-werror --enable-multilib
Thread model: posix
Supported LTO compression algorithms: zlib
gcc version 15.0.0 20240628 (experimental) (GCC)
[538] %
[538] % gcctk -O1 small.c; ./a.out
[539] %
[539] % gcctk -O1 -fipa-pta small.c
[540] % ./a.out
Aborted
[541] %
[541] % cat small.c
int a, c, d;
static int b;
int main() {
int *e = &a, **f = &e;
while (1) {
int **g, ***h = &f;
if (c)
*g = e;
else if (!b)
break;
*e = **g;
e = &d;
}
if (e != &a)
__builtin_abort();
return 0;
}
