diff --git a/src/thread/stdcpp/SDL_sysmutex.cpp b/src/thread/stdcpp/SDL_sysmutex.cpp
index df91a0d44..f5283e4a5 100644
--- a/src/thread/stdcpp/SDL_sysmutex.cpp
+++ b/src/thread/stdcpp/SDL_sysmutex.cpp
@@ -65,8 +65,6 @@ extern "C"
 int
 SDL_mutexP(SDL_mutex * mutex)
 {
-    SDL_threadID threadID = SDL_ThreadID();
-    DWORD realThreadID = GetCurrentThreadId();
     if (mutex == NULL) {
         SDL_SetError("Passed a NULL mutex");
         return -1;
@@ -86,8 +84,6 @@ extern "C"
 int
 SDL_mutexV(SDL_mutex * mutex)
 {
-    SDL_threadID threadID = SDL_ThreadID();
-    DWORD realThreadID = GetCurrentThreadId();
     if (mutex == NULL) {
         SDL_SetError("Passed a NULL mutex");
         return -1;