Use target_compile_options instead of modifying CMAKE_CXX_FLAGS.

CMakeLists.txt

@@ -1,23 +1,21 @@
-cmake_minimum_required(VERSION 2.8.11)
+cmake_minimum_required(VERSION 2.8.12)
 project(test_hopscotch_map)
 enable_testing()
 
 find_package(Boost 1.54.0 REQUIRED COMPONENTS unit_test_framework) 
 
-if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
-    #set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} -std=c++11 -Werror -Wall -Wextra -Wold-style-cast -g --coverage -DTSL_DEBUG")
-    set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} -std=c++11 -Werror -Wall -Wextra -Wold-style-cast -O3 -DTSL_DEBUG")
-elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
-    set(CMAKE_CXX_FLAGS  "${CMAKE_CXX_FLAGS} /WX /W3 /DTSL_DEBUG")
-endif()
-
 
 set(TEST_EXECUTABLE "test_hopscotch_map")
 
-
-
 add_executable("${TEST_EXECUTABLE}" "tests/main.cpp" "tests/hopscotch_map_tests.cpp" "tests/hopscotch_set_tests.cpp")
 target_include_directories("${TEST_EXECUTABLE}" PRIVATE "${Boost_INCLUDE_DIRS}" "src") 
 target_link_libraries("${TEST_EXECUTABLE}" ${Boost_LIBRARIES})
 
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+#    target_compile_options("${TEST_EXECUTABLE}" PRIVATE -std=c++11 -Werror -Wall -Wextra -Wold-style-cast -g --coverage -DTSL_DEBUG)
+    target_compile_options("${TEST_EXECUTABLE}" PRIVATE -std=c++11 -Werror -Wall -Wextra -Wold-style-cast -O3 -DTSL_DEBUG)
+elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
+    target_compile_options("${TEST_EXECUTABLE}" PRIVATE /WX /W3 /DTSL_DEBUG)
+endif()
+
 add_test(NAME "all_tests" COMMAND "${TEST_EXECUTABLE}")