handle locking more carefully (especially protect gc and stack shifting).

C/sysbits.c

@@ -1538,10 +1538,6 @@ ProcessSIGINT(void)
 
 #if !_MSC_VER && !defined(__MINGW32__)
 
-#if HAVE_SIGNAL
-static int             snoozing = FALSE;
-#endif
-
 /* This function is called from the signal handler to process signals.
    We assume we are within the context of the signal handler, whatever
    that might be