diff --git a/errors_test.go b/errors_test.go
index 1d29236ca..791741978 100644
--- a/errors_test.go
+++ b/errors_test.go
@@ -23,6 +23,7 @@ func TestErrors(t *testing.T) {
 		"loader-invaliddep",
 		"loader-invalidpackage",
 		"loader-nopackage",
+		"optimizer",
 		"syntax",
 		"types",
 	} {
diff --git a/testdata/errors/optimizer.go b/testdata/errors/optimizer.go
new file mode 100644
index 000000000..4e0d71b93
--- /dev/null
+++ b/testdata/errors/optimizer.go
@@ -0,0 +1,18 @@
+package main
+
+import "runtime/interrupt"
+
+var num = 5
+
+func main() {
+	// Error coming from LowerInterrupts.
+	interrupt.New(num, func(interrupt.Interrupt) {
+	})
+
+	// 2nd error
+	interrupt.New(num, func(interrupt.Interrupt) {
+	})
+}
+
+// ERROR: optimizer.go:9:15: interrupt ID is not a constant
+// ERROR: optimizer.go:13:15: interrupt ID is not a constant