handle `DebugMessage(M64MSG_ERROR` uniformly by using my new approach of kicking it to a vsync so the frontend can recover. In one particular case (trying to read from an unmapped memory range) this can result in emulation proceeding instead of just hanging the frontend, although the results from that point may be questionable.

libmupen64plus/mupen64plus-core/src/api/callbacks.c

@@ -55,6 +55,15 @@ void DebugMessage(int level, const char *message, ...)
 {
   char msgbuf[256];
   va_list args;
+	extern HANDLE rompausesem;
+	extern int stop;
+
+	if(level == M64MSG_ERROR)
+	{
+		//trigger a vsync just to get out of frame advance
+		new_vi(); 
+		WaitForSingleObject(rompausesem, INFINITE);
+	}
 
   if (pDebugFunc == NULL)
       return;

libmupen64plus/mupen64plus-core/src/r4300/pure_interp.c

@@ -394,7 +394,6 @@ static void prefetch(void)
    else
    {
       DebugMessage(M64MSG_ERROR, "prefetch() execute address :%x", PC->addr);
-      stop=1;
    }
 }
 

libmupen64plus/mupen64plus-core/src/r4300/r4300.c

@@ -236,9 +236,6 @@ static void NOTCOMPILED(void)
    else
 	 {
 		 DebugMessage(M64MSG_ERROR, "not compiled exception");
-		 //trigger a vsync just to get out of frame advance
-		 new_vi(); 
-		 WaitForSingleObject(rompausesem, INFINITE);
 	 }
 
 /*#ifdef DBG