diff --git a/webrtc/base/checks.h b/webrtc/base/checks.h
index d8be3ad594..fc3b329328 100644
--- a/webrtc/base/checks.h
+++ b/webrtc/base/checks.h
@@ -131,11 +131,11 @@ std::string* MakeCheckOpString<std::string, std::string>(
   inline std::string* Check##name##Impl(const t1& v1, const t2& v2, \
                                         const char* names) { \
     if (v1 op v2) return NULL; \
-    else return MakeCheckOpString(v1, v2, names); \
+    else return rtc::MakeCheckOpString(v1, v2, names); \
   } \
   inline std::string* Check##name##Impl(int v1, int v2, const char* names) { \
     if (v1 op v2) return NULL; \
-    else return MakeCheckOpString(v1, v2, names); \
+    else return rtc::MakeCheckOpString(v1, v2, names); \
   }
 DEFINE_CHECK_OP_IMPL(EQ, ==)
 DEFINE_CHECK_OP_IMPL(NE, !=)