https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117511
Bug ID: 117511 Summary: internal compiler error: Segmentation fault at mark_used(tree_node*, int) Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: yihan4845 at gmail dot com Target Milestone: --- Compiler Explorer: https://godbolt.org/z/KnW9jY9hM The following program: ```cpp template<unsigned N> struct S { }; template<typename T> class A { static char check(S<sizeof(U(0))>); public: static const bool value = (sizeof(check<T>(0)) == sizeof(char)); }; void foo() { A<int>::value; } ``` will trigger segmentation fault for gcc trunk. Stack dump: ``` 0x289ac95 diagnostic_context::diagnostic_impl(rich_location*, diagnostic_metadata const*, diagnostic_option_id, char const*, __va_list_tag (*) [1], diagnostic_t) ???:0 0x28b1685 internal_error(char const*, ...) ???:0 0xcc84b6 instantiate_decl(tree_node*, bool, bool) ???:0 0xb9380b mark_used(tree_node*, int) ???:0 0xd2e5ab finish_id_expression(tree_node*, tree_node*, tree_node*, cp_id_kind*, bool, bool, bool*, bool, bool, bool, bool, char const**, unsigned int) ???:0 0xca0a6a c_parse_file() ???:0 0xdfab69 c_common_parse_file() ???:0 Please submit a full bug report, with preprocessed source (by using -freport-bug). Please include the complete backtrace with any bug report. See <https://gcc.gnu.org/bugs/> for instructions. Compiler returned: 1 ```