Update graph_test.cc
diff --git a/src/graph_test.cc b/src/graph_test.cc
index c8cca1c..660943f 100644
--- a/src/graph_test.cc
+++ b/src/graph_test.cc
@@ -218,7 +218,7 @@
 "build a$ b: cat no'space with$ space$$ no\"space2\n"));
 
   Edge* edge = GetNode("a b")->in_edge();
-#if _WIN32
+#ifdef _WIN32
   EXPECT_EQ("cat no'space \"with space$\" \"no\\\"space2\" > \"a b\"",
       edge->EvaluateCommand());
 #else