What version of Go are you using (go version)?

gccgo tip

$ go version
go version go1.13 gccgo (GCC) 10.0.0 20190916 (experimental) linux/amd64

Does this issue reproduce with the latest release?

yes

What operating system and processor architecture are you using (go env)?

linux/amd64

What did you do?

Compile these two packages:

Package "a":

package a

type A struct {
	x int
}

//go:noinline
func W(a A, k, v interface{}) A {
	return A{3}
}

Package "b":

package b

import "a"

type B struct {
	s string
}

func (b B) Func(x a.A) a.A {
	return a.W(x, k, b)
}

type ktype int

const k ktype = 0

What did you expect to see?

clean compile

What did you see instead?

ICE with this stack trace:

go1: internal compiler error: in type_index, at go/gofrontend/export.cc:1265
0x8440c5 Export::type_index(Type const*)
	../../gcc-trunk/gcc/go/gofrontend/export.cc:1265
0x84419d Export::write_type_to(Type const*, Export_function_body*)
	../../gcc-trunk/gcc/go/gofrontend/export.cc:1287
0x8553b3 Export_function_body::write_type(Type const*)
	../../gcc-trunk/gcc/go/gofrontend/export.h:345
0x8553b3 Integer_expression::do_export(Export_function_body*) const
	../../gcc-trunk/gcc/go/gofrontend/expressions.cc:2531
0x850bb1 Expression::export_expression(Export_function_body*) const
	../../gcc-trunk/gcc/go/gofrontend/expressions.h:1054
0x850bb1 Type_conversion_expression::do_export(Export_function_body*) const
	../../gcc-trunk/gcc/go/gofrontend/expressions.cc:4268
0x85bbe7 Expression::export_expression(Export_function_body*) const
	../../gcc-trunk/gcc/go/gofrontend/expressions.h:1054
0x85bbe7 Call_expression::export_arguments(Export_function_body*) const
	../../gcc-trunk/gcc/go/gofrontend/expressions.cc:12398
0x88e96c Statement::export_statement(Export_function_body*)
	../../gcc-trunk/gcc/go/gofrontend/statements.h:340
0x88e96c Block::export_block(Export_function_body*)
	../../gcc-trunk/gcc/go/gofrontend/gogo.cc:6932
0x8d8f36 Block_statement::export_block(Export_function_body*, Block*, bool)
	../../gcc-trunk/gcc/go/gofrontend/statements.cc:2155
0x88e96c Statement::export_statement(Export_function_body*)
	../../gcc-trunk/gcc/go/gofrontend/statements.h:340
0x88e96c Block::export_block(Export_function_body*)
	../../gcc-trunk/gcc/go/gofrontend/gogo.cc:6932
0x89a8de Function::export_func_with_type(Export*, Named_object const*, Function_type const*, std::vector >*, bool, std::__cxx11::basic_string, std::allocator > const&, Block*, Location)
	../../gcc-trunk/gcc/go/gofrontend/gogo.cc:5987
0x89aed8 Function::export_func(Export*, Named_object const*) const
	../../gcc-trunk/gcc/go/gofrontend/gogo.cc:5841
0x89afa3 Named_object::export_named_object(Export*) const
	../../gcc-trunk/gcc/go/gofrontend/gogo.cc:8573
0x8e6efa Named_type::do_export(Export*) const
	../../gcc-trunk/gcc/go/gofrontend/types.cc:11132
0x84190a Type::export_type(Export*) const
	../../gcc-trunk/gcc/go/gofrontend/types.h:1076
0x84190a Export::write_type_definition(Type const*, int)
	../../gcc-trunk/gcc/go/gofrontend/export.cc:1206
0x841b8f Export::write_types(int)
	../../gcc-trunk/gcc/go/gofrontend/export.cc:1143

It looks as though the issue is with the constant, which is not getting picked up properly by the exporter.

Still working on a fix.