--- /src/net/json_util_test.cc
+++ /src/net/json_util_test.cc
@@ -784,13 +784,13 @@
   for (size_t i = 0; i <  arraysize(kNumS32ValueKeys); ++i) {
     {
       Json::Value json_value;
-      json_value[kNumS32ValueKeys[i]] = -2147483649ll;
+      json_value[kNumS32ValueKeys[i]] = static_cast<Json::Value::Int64>(-2147483649ll);
       TestMsg msg;
       EXPECT_FALSE(JsonUtil::JsonValueToProtobufMessage(json_value, &msg));
     }
     {
       Json::Value json_value;
-      json_value[kNumS32ValueKeys[i]] = 2147483648ull;
+      json_value[kNumS32ValueKeys[i]] = static_cast<Json::Value::UInt64>(2147483648ull);
       TestMsg msg;
       EXPECT_FALSE(JsonUtil::JsonValueToProtobufMessage(json_value, &msg));
     }
@@ -805,7 +805,7 @@
     }
     {
       Json::Value json_value;
-      json_value[kNumU32ValueKeys[i]] = 4294967296ull;
+      json_value[kNumU32ValueKeys[i]] = static_cast<Json::Value::UInt64>(4294967296ull);
       TestMsg msg;
       EXPECT_FALSE(JsonUtil::JsonValueToProtobufMessage(json_value, &msg));
     }