Enable -Wextra warnings

Author: rigtorp

CMakeLists.txt

@@ -49,7 +49,7 @@ set(GTEST_BINARY_DIR ${binary_dir})
 find_package(Threads)
 
 if(UNIX)
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -fexceptions -g -Wall -Wpedantic")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -fexceptions -g -Wall -Wpedantic -Wextra -Wno-unused-parameter")
     set(CMAKE_CXX_FLAGS_DEBUG "${CMAKE_CXX_FLAGS_DEBUG} -O0")
     set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Ofast")
 endif()