diff --git a/src/go/go2go/rewrite.go b/src/go/go2go/rewrite.go
index b84ffd0adc..3f34eb1a8c 100644
--- a/src/go/go2go/rewrite.go
+++ b/src/go/go2go/rewrite.go
@@ -25,7 +25,7 @@ var config = printer.Config{
 
 // isParameterizedFuncDecl reports whether fd is a parameterized function.
 func isParameterizedFuncDecl(fd *ast.FuncDecl, info *types.Info) bool {
-	if fd.Type.TParams != nil {
+	if fd.Type.TParams != nil && len(fd.Type.TParams.List) > 0 {
 		return true
 	}
 	if fd.Recv != nil {
@@ -64,7 +64,7 @@ func isTranslatableType(s ast.Spec, info *types.Info) bool {
 // isParameterizedTypeDecl reports whether s is a parameterized type.
 func isParameterizedTypeDecl(s ast.Spec, info *types.Info) bool {
 	ts := s.(*ast.TypeSpec)
-	if ts.TParams != nil {
+	if ts.TParams != nil && len(ts.TParams.List) > 0 {
 		return true
 	}
 	if ts.Assign == token.NoPos {
@@ -523,7 +523,7 @@ func (t *translator) translateFuncDecl(pd *ast.Decl) {
 		return
 	}
 	fd := (*pd).(*ast.FuncDecl)
-	if fd.Type.TParams != nil {
+	if fd.Type.TParams != nil && len(fd.Type.TParams.List) > 0 {
 		panic("parameterized function")
 	}
 	if fd.Recv != nil {
diff --git a/test/gen/g041.go2 b/test/gen/g041.go2
new file mode 100644
index 0000000000..0315f0cc72
--- /dev/null
+++ b/test/gen/g041.go2
@@ -0,0 +1,12 @@
+// compile
+
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Issue 40015.
+package p
+
+func F1(type)(s []int) {}
+
+func F2() { F1([]int{1, 2}) }