[Bug tree-optimization/79351] [7/8/9 Regression] Invalid tree PRE optimization around compound literal
amonakov at gcc dot gnu.org
gcc-bugzilla@gcc.gnu.org
Tue Nov 27 17:40:00 GMT 2018
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79351
Alexander Monakov <amonakov at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords| |wrong-code
Status|WAITING |NEW
CC| |amonakov at gcc dot gnu.org
Known to work| |4.3.2
Summary|Invalid tree PRE |[7/8/9 Regression] Invalid
|optimization around |tree PRE optimization
|compound literal |around compound literal
Known to fail| |4.7.2
--- Comment #4 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
Thanks, confirmed. Reduced testcase, aborts with -O -ftree-pre:
static struct state {
int k;
int dummy;
} states[256];
__attribute((noipa))
static void
ismatch(int n)
{
for (int j=0; j<n; j++) {
#if 1
states[j] = (struct state){0};
#else
__builtin_memset(states + j, 0, sizeof(states[0]));
#endif
for (int i = 0; i <= j; i++) {
states[i].k++;
}
}
}
int
main()
{
ismatch(2);
if (states[0].k != 2)
__builtin_abort();
}
More information about the Gcc-bugs
mailing list