https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103219
Aldy Hernandez <aldyh at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Last reconfirmed| |2021-11-14
Ever confirmed|0 |1
Status|UNCONFIRMED |NEW
--- Comment #1 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
Looks like a latent bug elsewhere as we're not threading anything. For that
matter, test fails even with -fno-thread-jumps.
$ ./cc1 a.c -O3 -fno-thread-jumps -quiet -w
during GIMPLE pass: unrolljam
a.c: In function ‘main’:
a.c:3:5: internal compiler error: Segmentation fault
3 | int main() {
| ^~~~
0x133a4fb crash_signal
Seems like tree_loop_unroll_and_jam is dereferencing a null return from
single_dom_exit():
auto_bitmap exit_bbs;
bitmap_set_bit (exit_bbs, single_dom_exit (outer)->dest->index);
todo |= do_rpo_vn (cfun, loop_preheader_edge (outer), exit_bbs);
(gdb) p debug(outer)
loop_1 (header = 9, latch = 26, niter = )
$6 = void
(gdb) p single_dom_exit (outer)
$7 = <edge 0x0>
