sdl12-compat: actually, the ThreadID functions cannot be PASSTHROUGH.

From dedf41f6a83bb0843a0bd5fb1ae84e3aa7eac413 Mon Sep 17 00:00:00 2001
From: Ozkan Sezer <[EMAIL REDACTED]>
Date: Wed, 3 Mar 2021 06:28:50 +0300
Subject: [PATCH] actually, the ThreadID functions cannot be PASSTHROUGH.

---
 src/SDL12_compat.c | 11 +++++++++++
 src/SDL20_syms.h   |  6 ++----
 2 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/SDL12_compat.c b/src/SDL12_compat.c
index 1cc1eeb..023543a 100644
--- a/src/SDL12_compat.c
+++ b/src/SDL12_compat.c
@@ -4097,6 +4097,17 @@ SDL_CreateThread(int (SDLCALL *fn)(void *), void *data)
 }
 #endif
 
+/* These two will truncate the returned value on LP64 systems,
+ * a shortcoming of SDL-1.2. */
+DECLSPEC Uint32 SDLCALL SDL_ThreadID(void)
+{
+    return SDL20_ThreadID();
+}
+DECLSPEC Uint32 SDLCALL SDL_GetThreadID(SDL_Thread *thread)
+{
+    return SDL20_GetThreadID(thread);
+}
+
 DECLSPEC int SDLCALL
 SDL_mutexP(SDL_mutex *mutex)
 {
diff --git a/src/SDL20_syms.h b/src/SDL20_syms.h
index 591a447..1f1359a 100644
--- a/src/SDL20_syms.h
+++ b/src/SDL20_syms.h
@@ -150,10 +150,8 @@ SDL20_SYM(SDL_Thread *,CreateThread,(SDL_ThreadFunction a, const char *b, void *
 SDL20_SYM(SDL_Thread *,CreateThread,(SDL_ThreadFunction a, const char *b, void *c),(a,b,c),return)
 #endif
 
-/* These two will truncate the returned value on LP64 systems,
- * a shortcoming of SDL-1.2.. */
-SDL20_SYM_PASSTHROUGH(Uint32,GetThreadID,(SDL_Thread *a),(a),return)
-SDL20_SYM_PASSTHROUGH(Uint32,ThreadID,(void),(),return)
+SDL20_SYM(unsigned long,GetThreadID,(SDL_Thread *a),(a),return)
+SDL20_SYM(unsigned long,ThreadID,(void),(),return)
 
 SDL20_SYM_PASSTHROUGH(void,WaitThread,(SDL_Thread *a, int *b),(a,b),)
 SDL20_SYM_PASSTHROUGH(SDL_mutex*,CreateMutex,(void),(),return)