gccgo: internal compiler error: in define

[dvyukov]

gccgo crashes on the following correct program:

package a
func f() {_:_:}

go1: internal compiler error: in define, at go/gofrontend/gogo.h:2680
0x61f965 Label::define(Location, Bindings_snapshot*)
    ../../gcc/go/gofrontend/gogo.h:2679
0x61f965 Function::add_label_definition(Gogo*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Location)
    ../../gcc/go/gofrontend/gogo.cc:4786
0x61facd Gogo::add_label_definition(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Location)
    ../../gcc/go/gofrontend/gogo.cc:1946
0x63bb95 Parse::labeled_stmt(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Location)
    ../../gcc/go/gofrontend/parse.cc:3749
0x63ba70 Parse::statement(Label*)
    ../../gcc/go/gofrontend/parse.cc:3646
0x63bc51 Parse::labeled_stmt(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Location)
    ../../gcc/go/gofrontend/parse.cc:3782
0x63ba70 Parse::statement(Label*)
    ../../gcc/go/gofrontend/parse.cc:3646
0x63bcad Parse::statement_list()
    ../../gcc/go/gofrontend/parse.cc:3918
0x63be37 Parse::block()
    ../../gcc/go/gofrontend/parse.cc:1142
0x646936 Parse::function_decl(bool)
    ../../gcc/go/gofrontend/parse.cc:2356
0x647343 Parse::program()
    ../../gcc/go/gofrontend/parse.cc:5689
0x60ede1 go_parse_input_files(char const**, unsigned int, bool, bool)
    ../../gcc/go/gofrontend/go.cc:73
0x60accf go_langhook_parse_file
    ../../gcc/go/go-lang.c:304

gofrontend is on commit 81810917af7ba19e1f9f8efc8b1989f7d6419d30

[dvyukov]

@ianlancetaylor

[gopherbot]

CL https://golang.org/cl/13907 mentions this issue.