diff --git a/src/gba/gba-thread.c b/src/gba/gba-thread.c
index b4072a196..3ffcfc502 100644
--- a/src/gba/gba-thread.c
+++ b/src/gba/gba-thread.c
@@ -21,11 +21,15 @@ static void* _GBAThreadRun(void* context) {
 	}
 
 	threadContext->gba = &gba;
-	threadContext->debugger = &debugger;
 	if (threadContext->fd >= 0) {
 		GBALoadROM(&gba, threadContext->fd);
 	}
-	GBAAttachDebugger(&gba, &debugger);
+	if (threadContext->useDebugger) {
+		threadContext->debugger = &debugger;
+		GBAAttachDebugger(&gba, &debugger);
+	} else {
+		threadContext->debugger = 0;
+	}
 	gba.keySource = &threadContext->activeKeys;
 
 	threadContext->started = 1;
@@ -33,8 +37,14 @@ static void* _GBAThreadRun(void* context) {
 	pthread_cond_broadcast(&threadContext->cond);
 	pthread_mutex_unlock(&threadContext->mutex);
 
-	ARMDebuggerRun(&debugger);
-	threadContext->started = 0;
+	if (threadContext->useDebugger) {
+		ARMDebuggerRun(&debugger);
+		threadContext->started = 0;
+	} else {
+		while (threadContext->started) {
+			ARMRun(&gba.cpu);
+		}
+	}
 	GBADeinit(&gba);
 
 	return 0;
diff --git a/src/gba/gba-thread.h b/src/gba/gba-thread.h
index 2270394ec..c1a454f38 100644
--- a/src/gba/gba-thread.h
+++ b/src/gba/gba-thread.h
@@ -6,6 +6,7 @@
 struct GBAThread {
 	// Output
 	int started;
+	int useDebugger;
 	struct GBA* gba;
 	struct ARMDebugger* debugger;
 
diff --git a/src/gl-main.c b/src/gl-main.c
index 3826e1ef9..cc246a822 100644
--- a/src/gl-main.c
+++ b/src/gl-main.c
@@ -65,6 +65,7 @@ int main(int argc, char** argv) {
 	}
 
 	context.fd = fd;
+	context.useDebugger = 0;
 	context.renderer = &renderer.d.d;
 	GBAThreadStart(&context);
 
@@ -118,7 +119,7 @@ static void _GBASDLRunloop(struct GBAThread* context, struct GLSoftwareRenderer*
 	glMatrixMode (GL_PROJECTION);
 	glLoadIdentity();
 	glOrtho(0, 240, 160, 0, 0, 1);
-	while (context->started && context->debugger->state != DEBUGGER_EXITING) {
+	while (context->started && (!context->debugger || context->debugger->state != DEBUGGER_EXITING)) {
 		pthread_mutex_lock(&renderer->d.mutex);
 		if (renderer->d.d.framesPending) {
 			renderer->d.d.framesPending = 0;
diff --git a/src/sdl/sdl-events.c b/src/sdl/sdl-events.c
index 440c4efe3..c787d2f9a 100644
--- a/src/sdl/sdl-events.c
+++ b/src/sdl/sdl-events.c
@@ -121,7 +121,11 @@ void GBASDLHandleEvent(struct GBAThread* context, const union SDL_Event* event)
 	switch (event->type) {
 	case SDL_QUIT:
 		// FIXME: this isn't thread-safe
-		context->debugger->state = DEBUGGER_EXITING;
+		if (context->debugger) {
+			context->debugger->state = DEBUGGER_EXITING;
+		} else {
+			context->started = 0;
+		}
 		break;
 	case SDL_KEYDOWN:
 	case SDL_KEYUP: