fix #1198

cl/compile_test.go

@@ -156,6 +156,50 @@ func main() {
 `)
 }
 
+func TestInterfaceBugNilUnderlying_Issue1198(t *testing.T) {
+	gopClTest(t, `
+import "runtime"
+
+type Outer interface{ Inner }
+
+type impl struct{}
+
+func New() Outer { return &impl{} }
+
+type Inner interface {
+	DoStuff() error
+}
+
+func (a *impl) DoStuff() error {
+	return nil
+}
+
+func main() {
+	var outer Outer = New()
+}
+`, `package main
+
+type Inner interface {
+	DoStuff() error
+}
+type Outer interface {
+	Inner
+}
+type impl struct {
+}
+
+func (a *impl) DoStuff() error {
+	return nil
+}
+func New() Outer {
+	return &impl{}
+}
+func main() {
+	var outer Outer = New()
+}
+`)
+}
+
 func TestInterfaceBugNilUnderlying_Issue1196(t *testing.T) {
 	gopClTest(t, `
 func main() {

cl/func_type_and_var.go

@@ -230,7 +230,7 @@ func toStructType(ctx *blockCtx, v *ast.StructType) *types.Struct {
 			if chkRedecl(name, field.Type.Pos()) {
 				continue
 			}
-			if t, ok := typ.(*types.Named); ok { // NOTE: embedded type should ensure loaded
+			if t, ok := typ.(*types.Named); ok { // #1196: embedded type should ensure loaded
 				ctx.loadNamed(ctx.pkg, t)
 			}
 			fld := types.NewField(token.NoPos, pkg, name, typ, true)
@@ -319,7 +319,11 @@ func toInterfaceType(ctx *blockCtx, v *ast.InterfaceType) types.Type {
 	var embeddeds []types.Type
 	for _, m := range methodsList {
 		if m.Names == nil { // embedded
-			embeddeds = append(embeddeds, toType(ctx, m.Type))
+			typ := toType(ctx, m.Type)
+			if t, ok := typ.(*types.Named); ok { // #1198: embedded type should ensure loaded
+				ctx.loadNamed(ctx.pkg, t)
+			}
+			embeddeds = append(embeddeds, typ)
 			continue
 		}
 		name := m.Names[0].Name

cmd/goptestgo/goptestgo.go

@@ -83,6 +83,7 @@ var (
 		"issue22662.go":     {},
 		"issue27201.go":     {},
 		"issue46903.go":     {},
+		"issue50190.go":     {}, // interesting, should be fixed
 		"nilptr_aix.go":     {},
 		"inline_literal.go": {},
 		"returntype.go":     {}, // not a problem