https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121758
Bug ID: 121758
Summary: ice with -O1 -ftree-loop-vectorize
-ftree-loop-distribution -fno-strict-aliasing
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: dcb314 at hotmail dot com
Target Milestone: ---
Created attachment 62266
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=62266&action=edit
C source code
The attached C code does this with recent gcc:
$ /home/dcb42/gcc/results.20250902.asan.ubsan/bin/gcc -w -c -O1
-ftree-loop-vectorize -ftree-loop-distribution -fno-strict-aliasing bug1120.c
during GIMPLE pass: vect
runData/keep/in.19936.c: In function ‘main’:
runData/keep/in.19936.c:1667:5: internal compiler error: in
vect_build_slp_tree_2, at tree-vect-slp.cc:3218
0x1ef3157 internal_error
/home/dcb42/gcc/working/gcc/../../trunk/gcc/diagnostic-global-context.cc:786
0x1efc81b fancy_abort
/home/dcb42/gcc/working/gcc/../../trunk/gcc/diagnostics/context.cc:1787
0xf897bb vect_build_slp_tree_2
/home/dcb42/gcc/working/gcc/../../trunk/gcc/tree-vect-slp.cc:3218
It seems fine a few days ago:
$ ../results.20250831.asan.ubsan/bin/gcc -c -w -O1 -ftree-loop-vectorize
-ftree-loop-distribution -fno-strict-aliasing bug1120.c
$
$ ../results.20250831.asan.ubsan/bin/gcc -v 2>&1 | grep exp
gcc version 16.0.0 20250831 (experimental) (d21f10259f64723f)
$ ../results.20250902.asan.ubsan/bin/gcc -v 2>&1 | grep exp
gcc version 16.0.0 20250902 (experimental) (dea668daa2ea8f9d)
$
I will run a reduction.
