diff --git a/test/checkkeys.c b/test/checkkeys.c
index bc4d7f126..89bae8eee 100644
--- a/test/checkkeys.c
+++ b/test/checkkeys.c
@@ -35,7 +35,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void
diff --git a/test/checkkeysthreads.c b/test/checkkeysthreads.c
index 23b93ebea..f245bc965 100644
--- a/test/checkkeysthreads.c
+++ b/test/checkkeysthreads.c
@@ -33,7 +33,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void
diff --git a/test/loopwave.c b/test/loopwave.c
index 7ebb01477..ac5f84d35 100644
--- a/test/loopwave.c
+++ b/test/loopwave.c
@@ -41,7 +41,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void
diff --git a/test/loopwavequeue.c b/test/loopwavequeue.c
index b28c6a8fc..e8c4daaab 100644
--- a/test/loopwavequeue.c
+++ b/test/loopwavequeue.c
@@ -40,7 +40,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int done = 0;
diff --git a/test/testaudiohotplug.c b/test/testaudiohotplug.c
index 333823cb0..61047a562 100644
--- a/test/testaudiohotplug.c
+++ b/test/testaudiohotplug.c
@@ -42,7 +42,10 @@ quit(int rc)
 {
     SDL_Quit();
     SDLTest_CommonDestroyState(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void SDLCALL
diff --git a/test/testautomation.c b/test/testautomation.c
index a017f4819..dab400902 100644
--- a/test/testautomation.c
+++ b/test/testautomation.c
@@ -52,7 +52,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 int main(int argc, char *argv[])
diff --git a/test/testcustomcursor.c b/test/testcustomcursor.c
index 9438613a6..12d54208c 100644
--- a/test/testcustomcursor.c
+++ b/test/testcustomcursor.c
@@ -144,7 +144,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void loop(void)
diff --git a/test/testdropfile.c b/test/testdropfile.c
index bb85afb50..acb016122 100644
--- a/test/testdropfile.c
+++ b/test/testdropfile.c
@@ -22,7 +22,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 int main(int argc, char *argv[])
diff --git a/test/testerror.c b/test/testerror.c
index 0b3c6541c..b52c206c8 100644
--- a/test/testerror.c
+++ b/test/testerror.c
@@ -25,7 +25,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int SDLCALL
diff --git a/test/testgeometry.c b/test/testgeometry.c
index e262ace8a..d494d9560 100644
--- a/test/testgeometry.c
+++ b/test/testgeometry.c
@@ -38,7 +38,10 @@ quit(int rc)
 {
     SDL_free(sprites);
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int LoadSprite(const char *file)
diff --git a/test/testgl.c b/test/testgl.c
index 21617c1bd..5cd03f9c1 100644
--- a/test/testgl.c
+++ b/test/testgl.c
@@ -65,7 +65,10 @@ static void quit(int rc)
         SDL_GL_DeleteContext(context);
     }
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void Render(void)
diff --git a/test/testgles.c b/test/testgles.c
index ecaa9d251..0afae5428 100644
--- a/test/testgles.c
+++ b/test/testgles.c
@@ -43,7 +43,10 @@ quit(int rc)
     }
 
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void
diff --git a/test/testgles2.c b/test/testgles2.c
index 7ea006992..b4ed5fe3c 100644
--- a/test/testgles2.c
+++ b/test/testgles2.c
@@ -100,7 +100,10 @@ quit(int rc)
     }
 
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 #define GL_CHECK(x)                                                                         \
diff --git a/test/testgles2_sdf.c b/test/testgles2_sdf.c
index 771091b4c..f0396bdb0 100644
--- a/test/testgles2_sdf.c
+++ b/test/testgles2_sdf.c
@@ -102,7 +102,10 @@ quit(int rc)
     }
 
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 #define GL_CHECK(x)                                                                         \
diff --git a/test/testlock.c b/test/testlock.c
index dd9c942e7..e9fd8bf22 100644
--- a/test/testlock.c
+++ b/test/testlock.c
@@ -65,7 +65,10 @@ static void closemutex(int sig)
         threads = NULL;
     }
     SDL_DestroyMutex(mutex);
-    exit(sig);
+    /* Let 'main()' return normally */
+    if (sig != 0) {
+        exit(sig);
+    }
 }
 
 static int SDLCALL
@@ -100,7 +103,7 @@ Run(void *data)
 }
 
 #ifndef _WIN32
-Uint32 hit_timeout(Uint32 interval, void *param) {
+static Uint32 hit_timeout(Uint32 interval, void *param) {
     SDL_Log("Hit timeout! Sending SIGINT!");
     kill(0, SIGINT);
     return 0;
diff --git a/test/testmessage.c b/test/testmessage.c
index 587a110ad..c490787d3 100644
--- a/test/testmessage.c
+++ b/test/testmessage.c
@@ -23,7 +23,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int SDLCALL
diff --git a/test/testnative.c b/test/testnative.c
index a58ce3ad5..ef587ede7 100644
--- a/test/testnative.c
+++ b/test/testnative.c
@@ -52,7 +52,10 @@ quit(int rc)
         factory->DestroyNativeWindow(native_window);
     }
     SDLTest_CommonDestroyState(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void MoveSprites(SDL_Renderer *renderer, SDL_Texture *sprite)
diff --git a/test/testoverlay.c b/test/testoverlay.c
index 6b9adefa5..abd97c40a 100644
--- a/test/testoverlay.c
+++ b/test/testoverlay.c
@@ -176,9 +176,9 @@ quit(int rc)
 
     SDLTest_CommonQuit(state);
 
-
+    /* Let 'main()' return normally */
     if (rc != 0) {
-        exit(rc);
+         exit(rc);
     }
 }
 
diff --git a/test/testpopup.c b/test/testpopup.c
index 475023642..6ce0b0bd5 100644
--- a/test/testpopup.c
+++ b/test/testpopup.c
@@ -47,8 +47,8 @@ struct PopupWindow
     int idx;
 };
 
-struct PopupWindow *menus;
-struct PopupWindow tooltip;
+static struct PopupWindow *menus;
+static struct PopupWindow tooltip;
 
 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
 static void quit(int rc)
@@ -57,7 +57,10 @@ static void quit(int rc)
     menus = NULL;
 
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int get_menu_index_by_window(SDL_Window *window)
@@ -115,7 +118,7 @@ static SDL_bool create_popup(struct PopupWindow *new_popup, SDL_bool is_menu)
     return SDL_FALSE;
 }
 
-static void close_popups()
+static void close_popups(void)
 {
     int i;
 
@@ -135,7 +138,7 @@ static void close_popups()
     }
 }
 
-static void loop()
+static void loop(void)
 {
     int i;
     char fmt_str[128];
diff --git a/test/testrendercopyex.c b/test/testrendercopyex.c
index 4c166a418..ffb522957 100644
--- a/test/testrendercopyex.c
+++ b/test/testrendercopyex.c
@@ -41,7 +41,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void Draw(DrawState *s)
diff --git a/test/testrendertarget.c b/test/testrendertarget.c
index 19b07fba2..abaf09c66 100644
--- a/test/testrendertarget.c
+++ b/test/testrendertarget.c
@@ -42,7 +42,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static SDL_bool
diff --git a/test/testscale.c b/test/testscale.c
index 1fa2975b2..16acb3f83 100644
--- a/test/testscale.c
+++ b/test/testscale.c
@@ -41,7 +41,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void Draw(DrawState *s)
diff --git a/test/testsem.c b/test/testsem.c
index 0010fcd13..a1706ca84 100644
--- a/test/testsem.c
+++ b/test/testsem.c
@@ -256,7 +256,7 @@ int main(int argc, char **argv)
 {
     int arg_count = 0;
     int i;
-    int init_sem;
+    int init_sem = 0;
     SDLTest_CommonState *state;
 
     /* Initialize test framework */
diff --git a/test/testsprite.c b/test/testsprite.c
index d1cbac14a..68b3b7b2d 100644
--- a/test/testsprite.c
+++ b/test/testsprite.c
@@ -57,9 +57,7 @@ quit(int rc)
     SDL_free(positions);
     SDL_free(velocities);
     SDLTest_CommonQuit(state);
-    /* If rc is 0, just let main return normally rather than calling exit.
-     * This allows testing of platforms where SDL_main is required and does meaningful cleanup.
-     */
+    /* Let 'main()' return normally */
     if (rc != 0) {
         exit(rc);
     }
diff --git a/test/testspriteminimal.c b/test/testspriteminimal.c
index 7a837de1b..b58d21d6e 100644
--- a/test/testspriteminimal.c
+++ b/test/testspriteminimal.c
@@ -40,7 +40,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void MoveSprites(void)
diff --git a/test/teststreaming.c b/test/teststreaming.c
index 4c6499649..dcd5b4423 100644
--- a/test/teststreaming.c
+++ b/test/teststreaming.c
@@ -64,13 +64,16 @@ static SDL_Renderer *renderer;
 static int frame;
 static SDL_Texture *MooseTexture;
 static SDL_bool done = SDL_FALSE;
-SDLTest_CommonState *state;
+static SDLTest_CommonState *state;
 
 static void quit(int rc)
 {
     SDL_Quit();
     SDLTest_CommonDestroyState(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void UpdateTexture(SDL_Texture *texture)
diff --git a/test/testthread.c b/test/testthread.c
index 15297e320..78560f928 100644
--- a/test/testthread.c
+++ b/test/testthread.c
@@ -22,7 +22,7 @@
 static SDL_TLSID tls;
 static int alive = 0;
 static int testprio = 0;
-SDLTest_CommonState *state;
+static SDLTest_CommonState *state;
 
 /* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
 static void
@@ -30,7 +30,10 @@ quit(int rc)
 {
     SDLTest_CommonDestroyState(state);
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static const char *
diff --git a/test/testviewport.c b/test/testviewport.c
index 004f3f047..006d3c244 100644
--- a/test/testviewport.c
+++ b/test/testviewport.c
@@ -38,7 +38,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void DrawOnViewport(SDL_Renderer *renderer)
diff --git a/test/testvulkan.c b/test/testvulkan.c
index 8eb98c986..dede60e94 100644
--- a/test/testvulkan.c
+++ b/test/testvulkan.c
@@ -187,7 +187,10 @@ static void quit(int rc)
 {
     shutdownVulkan(SDL_TRUE);
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static void loadGlobalFunctions(void)
diff --git a/test/testwm.c b/test/testwm.c
index 66a0df4fb..8066aa3af 100644
--- a/test/testwm.c
+++ b/test/testwm.c
@@ -47,7 +47,10 @@ static void
 quit(int rc)
 {
     SDLTest_CommonQuit(state);
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 /* Draws the modes menu, and stores the mode index under the mouse in highlighted_mode */
diff --git a/test/torturethread.c b/test/torturethread.c
index 4b8eeba5a..c2a0dd1a8 100644
--- a/test/torturethread.c
+++ b/test/torturethread.c
@@ -28,7 +28,10 @@ static void
 quit(int rc)
 {
     SDL_Quit();
-    exit(rc);
+    /* Let 'main()' return normally */
+    if (rc != 0) {
+        exit(rc);
+    }
 }
 
 static int SDLCALL