https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87616
--- Comment #1 from Michael Gorbovitski <mickg at mickg dot net> ---
> g++ prog.cc -Wall -Wextra
prog.cc:8:36: internal compiler error: Segmentation fault
8 | friend class friender<X,Y>::cls;
| ^
0xb3ffff crash_signal
../../source/gcc/toplev.c:325
0x644fc3 make_friend_class(tree_node*, tree_node*, bool)
../../source/gcc/cp/friend.c:406
0x6a409f cp_parser_template_declaration_after_parameters
../../source/gcc/cp/parser.c:27052
0x6a4421 cp_parser_explicit_template_declaration
../../source/gcc/cp/parser.c:27271
0x6a4421 cp_parser_template_declaration_after_export
../../source/gcc/cp/parser.c:27290
0x6913bd cp_parser_member_declaration
../../source/gcc/cp/parser.c:23593
0x6921c0 cp_parser_member_specification_opt
../../source/gcc/cp/parser.c:23520
0x6921c0 cp_parser_class_specifier_1
../../source/gcc/cp/parser.c:22664
0x693a9b cp_parser_class_specifier
../../source/gcc/cp/parser.c:22926
0x693a9b cp_parser_type_specifier
../../source/gcc/cp/parser.c:16910
0x69f4b8 cp_parser_decl_specifier_seq
../../source/gcc/cp/parser.c:13747
0x6a4780 cp_parser_simple_declaration
../../source/gcc/cp/parser.c:13057
0x6a8272 cp_parser_declaration
../../source/gcc/cp/parser.c:12876
0x6a89a6 cp_parser_translation_unit
../../source/gcc/cp/parser.c:4631
0x6a89a6 c_parse_file()
../../source/gcc/cp/parser.c:39116
0x75db8b c_common_parse_file()
../../source/gcc/c-family/c-opts.c:1139
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Please include the complete backtrace with any bug report.
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