From db5583e7211a933aba83a352a13c25b94bf2b9d0 Mon Sep 17 00:00:00 2001
From: Markus Baumeister <markus.baumeister1@rwth-aachen.de>
Date: Wed, 7 Mar 2018 16:18:51 +0100
Subject: [PATCH] Fix bug in CYCLE_TRANS_INT

The addition of CycleFromList uncovered a bug in CYCLE_TRANS_INT. This
patch by Max Horn hopefully fixes that.

His failure description (abbreviated) was:
The problem is that `AssPlist` can trigger a GC. The change by chance
happened to fill the heap in such a way that a GC happened at that spot
---
 src/trans.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/trans.c b/src/trans.c
index deb8071725..f0ea6c1ea1 100644
--- a/src/trans.c
+++ b/src/trans.c
@@ -3102,6 +3102,7 @@ Obj FuncCYCLE_TRANS_INT(Obj self, Obj f, Obj pt)
         i = cpt;
         do {
             AssPlist(out, ++len, INTOBJ_INT(i + 1));
+            ptf2 = CONST_ADDR_TRANS2(f);
             i = ptf2[i];
         } while (i != cpt);
     }
@@ -3116,6 +3117,7 @@ Obj FuncCYCLE_TRANS_INT(Obj self, Obj f, Obj pt)
         i = cpt;
         do {
             AssPlist(out, ++len, INTOBJ_INT(i + 1));
+            ptf4 = CONST_ADDR_TRANS4(f);
             i = ptf4[i];
         } while (i != cpt);
     }