- add a pr_double_remove cvar, that either ignores (0), warns about

(1), or causes a fatal error (2) when the progs remove an already
  removed entity.  default is 1.
- fix a segfault in FFnickFF parsing that causes a segfault

qw/source/sv_main.c

@@ -1897,6 +1897,7 @@ SV_InitLocal (void)
 	extern cvar_t *sv_wateraccelerate;
 	extern cvar_t *sv_friction;
 	extern cvar_t *sv_waterfriction;
+	extern cvar_t *pr_double_remove;
 
 	SV_UserInit ();
 
@@ -2056,6 +2057,12 @@ SV_InitLocal (void)
 	pr_gc_interval = Cvar_Get ("pr_gc_interval", "50", CVAR_NONE, NULL,
 							   "Number of frames to wait before running "
 							   "string garbage collector.");
+	pr_double_remove = Cvar_Get ("pr_double_remove", "1", CVAR_NONE, NULL,
+								 "Handling of double entity remove.  "
+								 "0 is silently ignore, 1 prints a "
+								 "traceback, and 2 gives an error.\n"
+								 "Only works if debugging is available "
+								 "and enabled");
 	// DoS protection
 	Cmd_AddCommand ("netdosexpire", SV_netDoSexpire_f, "FIXME: part of DoS "
 					"protection obviously, but I don't know what it does. No "

qw/source/sv_pr_cmds.c

@@ -641,12 +641,21 @@ PF_Spawn (progs_t *pr)
 	RETURN_EDICT (pr, ed);
 }
 
+cvar_t *pr_double_remove;
+
 void
 PF_Remove (progs_t *pr)
 {
 	edict_t    *ed;
 
 	ed = G_EDICT (pr, OFS_PARM0);
+	if (ed->free && pr_double_remove->int_val) {
+		if (pr_double_remove->int_val == 1) {
+			PR_DumpState (pr);
+			SV_Printf ("Double entity remove\n");
+		} else // == 2
+			PR_RunError (pr, "Double entity remove\n");
+	}
 	ED_Free (pr, ed);
 }
 

qw/source/sv_send.c

@@ -148,7 +148,7 @@ SV_Print (const char *fmt, va_list args)
 				int len;
 				int i;
 
-				if (!*end)
+				if (!end)
 					end = in + strlen (in);
 				*end = '\0';
 				for (i = 0; i < MAX_CLIENTS; i++) {