https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115508
--- Comment #5 from Sam James <sjames at gcc dot gnu.org> ---
On trunk with reduced.i, I get:
```
==3698089== Invalid read of size 8
==3698089== at 0x2430014: UnknownInlinedFun (tree-vect-slp.cc:9672)
==3698089== by 0x2430014: vect_schedule_slp_node(vec_info*, _slp_tree*,
_slp_instance*) (tree-vect-slp.cc:9514)
==3698089== by 0x242F05C: vect_schedule_scc(vec_info*, _slp_tree*,
_slp_instance*, hash_map<_slp_tree*, slp_scc_info,
simple_hashmap_traits<default_hash_traits<_slp_tree*>, slp_scc_in
fo> >&, int&, vec<_slp_tree*, va_heap, vl_ptr>&) (tree-vect-slp.cc:9965)
==3698089== by 0x242EFAC: vect_schedule_scc(vec_info*, _slp_tree*,
_slp_instance*, hash_map<_slp_tree*, slp_scc_info,
simple_hashmap_traits<default_hash_traits<_slp_tree*>, slp_scc_in
fo> >&, int&, vec<_slp_tree*, va_heap, vl_ptr>&) (tree-vect-slp.cc:9946)
==3698089== by 0x2139092: vect_schedule_slp(vec_info*, vec<_slp_instance*,
va_heap, vl_ptr> const&) (tree-vect-slp.cc:10110)
==3698089== by 0x1F013DB: vect_slp_region(vec<basic_block_def*, va_heap,
vl_ptr>, vec<data_reference*, va_heap, vl_ptr>, vec<int, va_heap, vl_ptr>*,
unsigned int, loop*) (tree-vect-sl
p.cc:8222)
==3698089== by 0x1EFD5B3: vect_slp_bbs(vec<basic_block_def*, va_heap,
vl_ptr> const&, loop*) [clone .lto_priv.0] (tree-vect-slp.cc:8322)
==3698089== by 0x1EFD2DA: vect_slp_function(function*)
(tree-vect-slp.cc:8444)
==3698089== by 0x1EFCC6C: (anonymous
namespace)::pass_slp_vectorize::execute(function*) [clone .lto_priv.0]
(tree-vectorizer.cc:1534)
==3698089== by 0x1B69A70: execute_one_pass(opt_pass*) (passes.cc:2647)
==3698089== by 0x1C2C09B: execute_pass_list_1(opt_pass*) (passes.cc:2756)
==3698089== by 0x1C2C0B8: execute_pass_list_1(opt_pass*) (passes.cc:2757)
==3698089== by 0x1C2C0B8: execute_pass_list_1(opt_pass*) (passes.cc:2757)
==3698089== Address 0x8 is not stack'd, malloc'd or (recently) free'd
==3698089==
during GIMPLE pass: slp
a.i: In function
‘FLAC__fixed_compute_best_predictor_limit_residual_intrin_avx2’:
a.i:5:6: internal compiler error: Segmentation fault
5 | void FLAC__fixed_compute_best_predictor_limit_residual_intrin_avx2(
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0x12a1362 crash_signal
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/toplev.cc:319
0x2430014 vect_schedule_slp_node
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:9672
0x2430014 vect_schedule_slp_node
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:9514
0x242f05c vect_schedule_scc
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:9965
0x242efac vect_schedule_scc
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:9946
0x2139092 vect_schedule_slp(vec_info*, vec<_slp_instance*, va_heap, vl_ptr>
const&)
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:10110
0x1f013db vect_slp_region
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:8222
0x1efd5b3 vect_slp_bbs
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:8322
0x1efd2da vect_slp_function(function*)
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vect-slp.cc:8444
0x1efcc6c execute
/usr/src/debug/sys-devel/gcc-15.0.9999/gcc-15.0.9999/gcc/tree-vectorizer.cc:1534
```
I think pinskia will be able to simplify my reduced version more..
