building Gtest framework in LINUX - c++

Question

I have downloaded the GTest sourcecode googletest-release-1.8.0.tar.gz (from : github ) and extracted it. (working on CentOS)
After that I ran following commands:
cd googletest-release-1.8.0\googletest.
cmake CMakeLists.txt.
Output:
-- Configuring done
-- Generating done
-- Build files have been written to: gtestframework/googletest-release-1.8.0/googletest
make.
Output:
[ 50%] Built target gtest
[100%] Built target gtest_main
After this I copied the file libgtest_main.a and libgtest.a into /usr/lib.
cd googletest-release-1.8.0\googlemock\gtest.
Copied libgtest_main.so libgtest.so libGTest.so in /usr/lib folder.
cd gtestframework\Testcode //{2 C++ files inside Testcode}
cmake CMakeLists.txt.
make.
I got this error:
Linking CXX executable runTests
CMakeFiles/runTests.dir/tests.cpp.o: In function `__static_initialization_and_destruction_0(int, int)':
tests.cpp:(.text+0x95a): undefined reference to `testing::internal::MakeAndRegisterTestInfo(char const*, char const*, char const*, char const*, testing::internal::CodeLocation, void const*, void (*)(), void (*)(), testing::internal::TestFactoryBase*)'
tests.cpp:(.text+0xa14): undefined reference to `testing::internal::MakeAndRegisterTestInfo(char const*, char const*, char const*, char const*, testing::internal::CodeLocation, void const*, void (*)(), void (*)(), testing::internal::TestFactoryBase*)'
CMakeFiles/runTests.dir/tests.cpp.o: In function `testing::AssertionResult testing::internal::CmpHelperEQFailure<int, double>(char const*, char const*, int const&, double const&)':
tests.cpp:(.text._ZN7testing8internal18CmpHelperEQFailureIidEENS_15AssertionResultEPKcS4_RKT_RKT0_[_ZN7testing8internal18CmpHelperEQFailureIidEENS_15AssertionResultEPKcS4_RKT_RKT0_]+0x6c): undefined reference to `testing::internal::EqFailure(char const*, char const*, std::string const&, std::string const&, bool)'
CMakeFiles/runTests.dir/tests.cpp.o: In function `testing::AssertionResult testing::internal::CmpHelperEQFailure<double, double>(char const*, char const*, double const&, double const&)':
tests.cpp:(.text._ZN7testing8internal18CmpHelperEQFailureIddEENS_15AssertionResultEPKcS4_RKT_RKT0_[_ZN7testing8internal18CmpHelperEQFailureIddEENS_15AssertionResultEPKcS4_RKT_RKT0_]+0x6c): undefined reference to `testing::internal::EqFailure(char const*, char const*, std::string const&, std::string const&, bool)'
collect2: error: ld returned 1 exit status
make[2]: *** [runTests] Error 1
make[1]: *** [CMakeFiles/runTests.dir/all] Error 2
make: *** [all] Error 2
CMakeLists.txt file content:
cmake_minimum_required(VERSION 2.6)
# Locate GTest
find_package(GTest REQUIRED)
include_directories(${GTEST_INCLUDE_DIRS})
# Link runTests with what we want to test and the GTest and pthread library
add_executable(runTests tests.cpp)
target_link_libraries(runTests ${GTEST_LIBRARIES} pthread)