http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60065
Bug ID: 60065 Summary: [c++1y] ICE with auto parameter pack Product: gcc Version: 4.9.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: reichelt at gcc dot gnu.org The following line of code (compiled with "-std=c++1y") triggers an ICE on trunk: ======================================== template<int> void foo(auto... x); ======================================== bug.cc:1:32: internal compiler error: tree check: expected template_type_parm or template_template_parm or bound_template_template_parm, have integer_type in convert_generic_types_to_packs, at cp/pt.c:21726 template<int> void foo(auto... x); ^ 0xdc4824 tree_check_failed(tree_node const*, char const*, int, char const*, ...) ../../gcc/gcc/tree.c:9192 0x64ad63 tree_check3 ../../gcc/gcc/tree.h:2749 0x64ad63 convert_generic_types_to_packs(tree_node*, int, int) ../../gcc/gcc/cp/pt.c:21726 0x6c8f47 cp_parser_parameter_declaration_list ../../gcc/gcc/cp/parser.c:18279 0x6c9532 cp_parser_parameter_declaration_clause ../../gcc/gcc/cp/parser.c:18179 0x6bfd05 cp_parser_direct_declarator ../../gcc/gcc/cp/parser.c:17072 0x6bfd05 cp_parser_declarator ../../gcc/gcc/cp/parser.c:16943 0x6ca599 cp_parser_init_declarator ../../gcc/gcc/cp/parser.c:16496 0x6cb41a cp_parser_single_declaration ../../gcc/gcc/cp/parser.c:23113 0x6cb704 cp_parser_template_declaration_after_export ../../gcc/gcc/cp/parser.c:22915 0x6d6af9 cp_parser_declaration ../../gcc/gcc/cp/parser.c:10947 0x6d55e8 cp_parser_declaration_seq_opt ../../gcc/gcc/cp/parser.c:10869 0x6d6eca cp_parser_translation_unit ../../gcc/gcc/cp/parser.c:4014 0x6d6eca c_parse_file() ../../gcc/gcc/cp/parser.c:31528 0x7f6973 c_common_parse_file() ../../gcc/gcc/c-family/c-opts.c:1060 Please submit a full bug report, [etc.] The code compiles if I remove the 'x' or replace 'int' by 'typename'. I'm not sure whether the code is valid or not, though.