From 4835199125415dbd40d863ea945a71bab9b6962b Mon Sep 17 00:00:00 2001
From: Araq <rumpf_a@web.de>
Date: Sat, 5 Apr 2014 21:05:07 +0200
Subject: [PATCH] new VM: proper shield against endless recursions

---
 compiler/vm.nim | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/compiler/vm.nim b/compiler/vm.nim
index b365dba9a..fb8749250 100644
--- a/compiler/vm.nim
+++ b/compiler/vm.nim
@@ -48,9 +48,17 @@ type
                               # XXX 'break' should perform cleanup actions
                               # What does the C backend do for it?
 
-proc stackTraceAux(c: PCtx; x: PStackFrame; pc: int) =
+proc stackTraceAux(c: PCtx; x: PStackFrame; pc: int; recursionLimit=100) =
   if x != nil:
-    stackTraceAux(c, x.next, x.comesFrom)
+    if recursionLimit == 0:
+      var calls = 0
+      var x = x
+      while x != nil:
+        inc calls
+        x = x.next
+      msgWriteln($calls & " calls omitted\n")
+      return
+    stackTraceAux(c, x.next, x.comesFrom, recursionLimit-1)
     var info = c.debug[pc]
     # we now use the same format as in system/except.nim
     var s = toFilename(info)