CMakeLists.txt: fixes

CMakeLists.txt

@@ -9,11 +9,11 @@ if(NOT EMSCRIPTEN)
 endif()
 
 # CMake actually has no default configuration and it's toolchain file dependent, set debug if not specified
-if(NOT CMAKE_BUILD_TYPE)
+if(NOT DEFINED CMAKE_BUILD_TYPE)
         set(CMAKE_BUILD_TYPE Debug)
 endif()
 
-if(NOT TWN_SANITIZE AND CMAKE_BUILD_TYPE MATCHES Debug)
+if(NOT DEFINED TWN_SANITIZE AND CMAKE_BUILD_TYPE MATCHES Debug)
         set(TWN_SANITIZE ON)
 endif()
 
@@ -183,7 +183,7 @@ function(give_options_without_warnings target)
                                       $<$<CONFIG:Release>:${BUILD_FLAGS_RELEASE}>
                                       $<$<CONFIG:Debug>:${BUILD_FLAGS_DEBUG}>
                                       -Bsymbolic-functions
-                                      -Wl,--hash-style=gnu)
+                                      $<$<BOOL:${LINUX}>:-Wl,--hash-style=gnu>)
 
         target_compile_definitions(${target} PRIVATE
                                              $<$<BOOL:${TWN_FEATURE_DYNLIB_GAME}>:TWN_FEATURE_DYNLIB_GAME>