diff --git a/src/cmd/compile/internal/types2/fixedbugs/issue43125.src b/src/cmd/compile/internal/types2/fixedbugs/issue43125.src
new file mode 100644
index 0000000000..c2bd970e25
--- /dev/null
+++ b/src/cmd/compile/internal/types2/fixedbugs/issue43125.src
@@ -0,0 +1,8 @@
+// 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.
+
+package p
+
+var _ = new(- /* ERROR not a type */ 1)
+var _ = new(1 /* ERROR not a type */ + 1)
diff --git a/src/cmd/compile/internal/types2/typexpr.go b/src/cmd/compile/internal/types2/typexpr.go
index 22df01b3be..4231577a4f 100644
--- a/src/cmd/compile/internal/types2/typexpr.go
+++ b/src/cmd/compile/internal/types2/typexpr.go
@@ -535,6 +535,9 @@ func (check *Checker) typInternal(e0 syntax.Expr, def *Named) (T Type) {
 			return typ
 		}
 
+		check.errorf(e0, "%s is not a type", e0)
+		check.use(e0)
+
 	case *syntax.FuncType:
 		typ := new(Signature)
 		def.setUnderlying(typ)