https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119973
Bug ID: 119973
Summary: [15/16 Regression] Wrong code at -O1 -fipa-pta -flto
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: ipa
Assignee: unassigned at gcc dot gnu.org
Reporter: xry111 at gcc dot gnu.org
Target Milestone: ---
$ cat bug.c
int
is_valid_domain_name (const char *string)
{
const char *s;
for (s=string; *s; s++)
if (*s == '.')
{
if (string == s)
return 0;
}
return !!*string;
}
int
main (void)
{
static struct
{
const char *name;
int valid;
} testtbl[] =
{
{ ".", 0 },
{ nullptr, 0 }
};
int idx;
for (idx=0; testtbl[idx].name; idx++)
{
if (is_valid_domain_name (testtbl[idx].name) != testtbl[idx].valid)
__builtin_abort ();
}
}
$ cc bug.c -std=c23 -O1 -fipa-pta -flto
$ ./a.out
[1] 301695 IOT instruction (core dumped) ./a.out
Removing any of -fipa-pta -flto can work around the issue. The code is reduced
from gnupg-2.4.7, it only fails at -O1 but the original gnupg code fails at -O2
and -O3 as well.
The output of GCC 14 is fine.
