https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82985
--- Comment #16 from Markus Trippelsdorf <trippels at gcc dot gnu.org> --- Created attachment 42606 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=42606&action=edit somewhat reduced testcase (Creduce struggles with 7.6MB boost testcases...) % g++ -mavx2 -c -O2 FullSystemOptimize.ii -w FullSystemOptimize.ii: In member function ‘bool std::FullSystem::doStepFromBackup()’: FullSystemOptimize.ii:446:6: internal compiler error: in vn_nary_build_or_lookup_1, at tree-ssa-sccvn.c:1722 bool FullSystem::doStepFromBackup() { ^~~~~~~~~~ 0xc52643 vn_nary_build_or_lookup_1 ../../gcc/gcc/tree-ssa-sccvn.c:1722 0xc546a9 vn_nary_build_or_lookup ../../gcc/gcc/tree-ssa-sccvn.c:1758 0xc546a9 vn_reference_lookup_3 ../../gcc/gcc/tree-ssa-sccvn.c:2037 0xbbe6fe walk_non_aliased_vuses(ao_ref*, tree_node*, void* (*)(ao_ref*, tree_node*, unsigned int, void*), void* (*)(ao_ref*, tree_node*, void*, bool*), tree_node* (*)(tree_node*), void*) ../../gcc/gcc/tree-ssa-alias.c:2872 0xc53179 vn_reference_lookup(tree_node*, tree_node*, vn_lookup_kind, vn_reference_s**, bool) ../../gcc/gcc/tree-ssa-sccvn.c:2450 0xc558e0 visit_reference_op_load ../../gcc/gcc/tree-ssa-sccvn.c:3691 0xc558e0 visit_use ../../gcc/gcc/tree-ssa-sccvn.c:4031 0xc57050 process_scc ../../gcc/gcc/tree-ssa-sccvn.c:4293 0xc57050 extract_and_process_scc_for_name ../../gcc/gcc/tree-ssa-sccvn.c:4349 0xc57050 DFS ../../gcc/gcc/tree-ssa-sccvn.c:4401 0xc58496 sccvn_dom_walker::before_dom_children(basic_block_def*) ../../gcc/gcc/tree-ssa-sccvn.c:4854 0x10ea63a dom_walker::walk(basic_block_def*) ../../gcc/gcc/domwalk.c:265 0xc5905a run_scc_vn(vn_lookup_kind) ../../gcc/gcc/tree-ssa-sccvn.c:4978 0xc356df execute ../../gcc/gcc/tree-ssa-pre.c:5093
