diff --git a/mach/proto/as/comm7.c b/mach/proto/as/comm7.c
index 9b93139d4..969d0d84a 100644
--- a/mach/proto/as/comm7.c
+++ b/mach/proto/as/comm7.c
@@ -86,6 +86,9 @@ char* remember(char* s)
 
 int combine(int typ1, int typ2, int op)
 {
+	typ1 &= ~S_VAR;
+	typ2 &= ~S_VAR;
+
 	switch (op)
 	{
 		case '+':
@@ -112,6 +115,7 @@ int combine(int typ1, int typ2, int op)
 				return (S_ABS);
 			break;
 	}
+	fprintf(stderr, "typ1=%d typ2=%d pass=%d\n", typ1, typ2, pass);
 	if (pass != PASS_1)
 		serror("illegal operator");
 	return (S_UND);