build: Windows does not imply MSVC

Author: rpavlik

src/tests/list/CMakeLists.txt

@@ -35,14 +35,14 @@ if(VulkanHeaders_FOUND)
     )
 endif()
 
-if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+target_link_libraries(runtime_list openxr_loader)
+if(MSVC)
     target_compile_options(runtime_list PRIVATE /Zc:wchar_t /Zc:forScope /W4 /WX)
-    target_link_libraries(runtime_list openxr_loader)
 endif()
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Linux")
     target_compile_options(runtime_list PRIVATE -Wall)
-    target_link_libraries(runtime_list openxr_loader pthread)
+    target_link_libraries(runtime_list pthread)
 endif()
 
 set_target_properties(runtime_list PROPERTIES FOLDER ${TESTS_FOLDER})

src/tests/loader_test/CMakeLists.txt

@@ -43,8 +43,10 @@ if(VulkanHeaders_FOUND)
 endif()
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
-    target_compile_definitions(loader_test PRIVATE _CRT_SECURE_NO_WARNINGS)
-    target_compile_options(loader_test PRIVATE /Zc:wchar_t /Zc:forScope /W4 /WX)
+    if(MSVC)
+        target_compile_definitions(loader_test PRIVATE _CRT_SECURE_NO_WARNINGS)
+        target_compile_options(loader_test PRIVATE /Zc:wchar_t /Zc:forScope /W4 /WX)
+    endif()
     target_link_libraries(loader_test openxr_loader opengl32 d3d11)
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
     target_compile_options(