title: why GoogleMock reports not match with exact same arguments value?
body: <p>The pure virtual class</p>
  
  <pre class="lang-cpp prettyprint-override"><code>class ConfigGetter {
   public:
    virtual const std::string Get(const char *name,
                                  const char *default_value) const = 0;
  };
  </code></pre>
  
  <p>The mock</p>
  
  <pre class="lang-cpp prettyprint-override"><code>class MockConfigGetter : public engine::ConfigGetter {
   public:
    MOCK_CONST_METHOD2(Get, const std::string(const char *, const char *));
  };
  </code></pre>
  
  <p>Test case</p>
  
  <pre class="lang-cpp prettyprint-override"><code>TEST(ConfigTest, NormalString) {
    NiceMock&lt;MockConfigGetter&gt; getter;
    EXPECT_CALL(getter, Get("SERVER_LISTEN_PORT", ""))
        .WillRepeatedly(Return("80"));
    // Pass
    ASSERT_EQ("80", getter.Get("SERVER_LISTEN_PORT", ""));
    // GetNewConfig internal call getter-&gt;Get("SERVER_LISTEN_PORT", "")
    auto f = engine::GetNewConfig(&amp;getter);
    ASSERT_NE(f, nullptr);
    // Failure
    ASSERT_EQ(80, f-&gt;listen_port);
  }
  </code></pre>
  
  <p>And good mock reports:</p>
  
  <pre><code>Unexpected mock function call - returning default value.
      Function call: Get(0x556fb6ea4860 pointing to "SERVER_LISTEN_PORT", 0x556fb6ea4843 pointing to "")
            Returns: ""
  Google Mock tried the following 1 expectation, but it didn't match:
  
  /home/phillip/projects/engine-test/src/config/config-test.cpp:26: EXPECT_CALL(getter, Get("SERVER_LISTEN_PORT", ""))...
    Expected arg #0: is equal to 0x556fb6ea2878 pointing to "SERVER_LISTEN_PORT"
             Actual: 0x556fb6ea4860 pointing to "SERVER_LISTEN_PORT"
    Expected arg #1: is equal to 0x556fb6ea27bc pointing to ""
             Actual: 0x556fb6ea4843 pointing to ""
           Expected: to be called any number of times
             Actual: called twice - satisfied and active
  </code></pre>
  
  <p>arg0 and arg1 is exactly the same as EXPECT_CALL. I don't know why the second call fail to match.</p>