Don't automatically free temporary memory, let the application call SDL_FreeTemporaryMemory() when it's ready.

Also mark up all functions that return temporary memory with SDL_DECLSPEC_TEMP, to help people implementing language bindings.

Fixes https://github.com/libsdl-org/SDL/issues/10378

src/dynapi/SDL_dynapi.sym

@@ -130,6 +130,7 @@ SDL3_0.0.0 {
     SDL_FlushEvent;
     SDL_FlushEvents;
     SDL_FlushRenderer;
+    SDL_FreeTemporaryMemory;
     SDL_GDKSuspendComplete;
     SDL_GL_CreateContext;
     SDL_GL_DestroyContext;

src/dynapi/SDL_dynapi_overrides.h

@@ -155,6 +155,7 @@
 #define SDL_FlushEvent SDL_FlushEvent_REAL
 #define SDL_FlushEvents SDL_FlushEvents_REAL
 #define SDL_FlushRenderer SDL_FlushRenderer_REAL
+#define SDL_FreeTemporaryMemory SDL_FreeTemporaryMemory_REAL
 #define SDL_GDKSuspendComplete SDL_GDKSuspendComplete_REAL
 #define SDL_GL_CreateContext SDL_GL_CreateContext_REAL
 #define SDL_GL_DestroyContext SDL_GL_DestroyContext_REAL

src/dynapi/SDL_dynapi_procs.h

@@ -175,6 +175,7 @@ SDL_DYNAPI_PROC(int,SDL_FlushAudioStream,(SDL_AudioStream *a),(a),return)
 SDL_DYNAPI_PROC(void,SDL_FlushEvent,(Uint32 a),(a),)
 SDL_DYNAPI_PROC(void,SDL_FlushEvents,(Uint32 a, Uint32 b),(a,b),)
 SDL_DYNAPI_PROC(int,SDL_FlushRenderer,(SDL_Renderer *a),(a),return)
+SDL_DYNAPI_PROC(void,SDL_FreeTemporaryMemory,(void),(),)
 SDL_DYNAPI_PROC(void,SDL_GDKSuspendComplete,(void),(),)
 SDL_DYNAPI_PROC(SDL_GLContext,SDL_GL_CreateContext,(SDL_Window *a),(a),return)
 SDL_DYNAPI_PROC(int,SDL_GL_DestroyContext,(SDL_GLContext a),(a),return)

src/dynapi/gendynapi.py

@@ -197,6 +197,7 @@ def main():
             func_ret = func_ret.replace('extern', ' ')
             func_ret = func_ret.replace('SDLCALL', ' ')
             func_ret = func_ret.replace('SDL_DECLSPEC', ' ')
+            func_ret = func_ret.replace('SDL_DECLSPEC_TEMP', ' ')
             # Remove trailing spaces in front of '*'
             tmp = ""
             while func_ret != tmp: