diff --git a/.gitignore b/.gitignore
index 3a5347a1..1c088b81 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 .*.swo
 .*.swp
 *.dot
+*.out
 .idea/
 /yaegi
 internal/cmd/extract/extract
diff --git a/_test/op10.go b/_test/op10.go
new file mode 100644
index 00000000..5db58094
--- /dev/null
+++ b/_test/op10.go
@@ -0,0 +1,9 @@
+package main
+
+func main() {
+	_ = 1 + 1
+	println("ok")
+}
+
+// Output:
+// ok
diff --git a/_test/op11.go b/_test/op11.go
new file mode 100644
index 00000000..ab2ecfa3
--- /dev/null
+++ b/_test/op11.go
@@ -0,0 +1,10 @@
+package main
+
+func main() {
+	a, b := 1, 2
+	_ = a + b
+	println("ok")
+}
+
+// Output:
+// ok
diff --git a/interp/type.go b/interp/type.go
index 2e7c1ffc..b3220455 100644
--- a/interp/type.go
+++ b/interp/type.go
@@ -2393,7 +2393,7 @@ func isMap(t *itype) bool  { return t.TypeOf().Kind() == reflect.Map }
 func isPtr(t *itype) bool  { return t.TypeOf().Kind() == reflect.Ptr }
 
 func isEmptyInterface(t *itype) bool {
-	return t.cat == interfaceT && len(t.field) == 0
+	return t != nil && t.cat == interfaceT && len(t.field) == 0
 }
 
 func isGeneric(t *itype) bool {