https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101099
Bug ID: 101099 Summary: [9/10/11/12 Regression] ICE in type_unification_real, at cp/pt.c:22173 Product: gcc Version: 12.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: gs...@t-online.de Target Milestone: --- Started with r9 between and 20190615 and 20190727, r8 accepts it. With options -std=gnu++11 -fconcepts and several testsuite files or the following variant : $ cat z1.cc #include <initializer_list> constexpr auto list = { 1, 2, 3 }; $ g++-8 -c z1.cc -std=gnu++11 -fconcepts $ $ g++-12-20210613 -c z1.cc -std=gnu++11 -fconcepts z1.cc:2:33: internal compiler error: in type_unification_real, at cp/pt.c:22173 2 | constexpr auto list = { 1, 2, 3 }; | ^ 0x8313d8 type_unification_real ../../gcc/cp/pt.c:22173 0x819606 do_auto_deduction(tree_node*, tree_node*, tree_node*, int, auto_deduction_context, tree_node*, int) ../../gcc/cp/pt.c:29619 0x745bf6 cp_finish_decl(tree_node*, tree_node*, bool, tree_node*, int) ../../gcc/cp/decl.c:7834 0x802791 cp_parser_init_declarator ../../gcc/cp/parser.c:22044 0x7e348a cp_parser_simple_declaration ../../gcc/cp/parser.c:14587 0x8081f5 cp_parser_declaration ../../gcc/cp/parser.c:14284 0x80770b cp_parser_translation_unit ../../gcc/cp/parser.c:4942 0x80770b c_parse_file() ../../gcc/cp/parser.c:45611 0x8d7412 c_common_parse_file() ../../gcc/c-family/c-opts.c:1219