Gmock Linking Error

### Describe the issue

I am using Gtest and Gmock with MingW, The following linking error is occurring for me.

### Steps to reproduce the problem

undefined reference to 'testing::internal::GetWithouMatchers();
undefined reference to 'testing::internal::UntypedFunctionMockBase();

etc...

### What version of GoogleTest are you using?

Cmake Command : g++ testRunner.cpp -lgtest -lgmock -lpthread -lgtest_main -lgmock_main

### What operating system and version are you using?

Mingw

### What compiler and version are you using?

g++ testRunner.cpp -lgtest -lgmock -lpthread -lgtest_main -lgmock_main

### What build system are you using?

Cmake version (3.7)

### Additional context

undefined reference to 'testing::internal::GetWithouMatchers();
undefined reference to 'testing::internal::UntypedFunctionMockBase();