https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88690
--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> --- Reduced test-case: $ cat services.ii typedef char a; using b = int; class c { b f{5}; }; class d { int e{}; }; class C { C() = delete; }; class i : public d, public C {}; template <int, typename, int, class> using g = i; enum { h }; using code = int; struct : c { enum k : a; g<h, k, h, code> j; } ags{}; $ /home/marxin/Programming/gcc2/objdir/gcc/xgcc -B/home/marxin/Programming/gcc2/objdir/gcc/ -std=c++17 services.ii -c services.ii:19:8: internal compiler error: in output_constructor_regular_field, at varasm.c:5202 19 | } ags{}; | ^ 0x7c4774 output_constructor_regular_field ../../gcc/varasm.c:5202 0x7c4774 output_constructor ../../gcc/varasm.c:5512 0x126aac3 output_constant ../../gcc/varasm.c:5241 0x126aac3 output_constructor_regular_field ../../gcc/varasm.c:5241 0x126aac3 output_constructor ../../gcc/varasm.c:5512 0x126c152 output_constant ../../gcc/varasm.c:4880 0x126c152 assemble_variable_contents ../../gcc/varasm.c:2144 0x12719d6 assemble_variable(tree_node*, int, int, int) ../../gcc/varasm.c:2323 0x12768e9 varpool_node::assemble_decl() ../../gcc/varpool.c:586 0x12768e9 varpool_node::assemble_decl() ../../gcc/varpool.c:554 0xb6fb5b output_in_order ../../gcc/cgraphunit.c:2444 0xb6fb5b symbol_table::compile() ../../gcc/cgraphunit.c:2684 0xb6fb5b symbol_table::compile() ../../gcc/cgraphunit.c:2595 0xb71cf5 symbol_table::finalize_compilation_unit() ../../gcc/cgraphunit.c:2863