http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55232
--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> 2012-11-07 14:03:40 UTC --- Specifically, -Wunused-parameter struct vector { typedef int value_type; }; template< class... T > struct X { void push_back( typename T::value_type ... vals ) { } }; int main() { X< vector > x; x.push_back( 0 ); } ' in dependent_type_p, at cp/pt.c:19250 } ^ 0x56ee10 dependent_type_p ../../gcc-4.8-20121104/gcc/cp/pt.c:19250 0x56f744 dependent_scope_p(tree_node*) ../../gcc-4.8-20121104/gcc/cp/pt.c:19281 0x5391f9 make_typename_type(tree_node*, tree_node*, tag_types, int) ../../gcc-4.8-20121104/gcc/cp/decl.c:3273 0x5948f9 tsubst ../../gcc-4.8-20121104/gcc/cp/pt.c:11546 0x5948f9 tsubst ../../gcc-4.8-20121104/gcc/cp/pt.c:10950 0x60360c dump_template_bindings ../../gcc-4.8-20121104/gcc/cp/error.c:325 0x5fc5ff dump_function_decl ../../gcc-4.8-20121104/gcc/cp/error.c:1441 0x605e9c decl_to_string ../../gcc-4.8-20121104/gcc/cp/error.c:2688 0x605e9c cp_printer ../../gcc-4.8-20121104/gcc/cp/error.c:3278 0x605e9c cp_printer ../../gcc-4.8-20121104/gcc/cp/error.c:3245 0xf2f5c8 pp_base_format(pretty_print_info*, text_info*) ../../gcc-4.8-20121104/gcc/pretty-print.c:509 0xf3059f pp_base_format_verbatim(pretty_print_info*, text_info*) ../../gcc-4.8-20121104/gcc/pretty-print.c:565 0xf30687 pp_verbatim(pretty_print_info*, char const*, ...) ../../gcc-4.8-20121104/gcc/pretty-print.c:749 0x5f82a1 print_instantiation_full_context ../../gcc-4.8-20121104/gcc/cp/error.c:3053 0x5f82a1 maybe_print_instantiation_context ../../gcc-4.8-20121104/gcc/cp/error.c:3193 0x5f82a1 maybe_print_instantiation_context ../../gcc-4.8-20121104/gcc/cp/error.c:3187 0x6047c5 cp_diagnostic_starter ../../gcc-4.8-20121104/gcc/cp/error.c:2881 0xf2cfc8 diagnostic_report_diagnostic(diagnostic_context*, diagnostic_info*) ../../gcc-4.8-20121104/gcc/diagnostic.c:757 0xf2e3e5 warning(int, char const*, ...) ../../gcc-4.8-20121104/gcc/diagnostic.c:918 0x8e7864 do_warn_unused_parameter(tree_node*) ../../gcc-4.8-20121104/gcc/function.c:4965 Please submit a full bug report, with preprocessed source if appropriate. Please include the complete backtrace with any bug report. See <http://gcc.gnu.org/bugs.html> for instructions.