From f6d58bc94752f02fabe46ec5e06890a0b01a1343 Mon Sep 17 00:00:00 2001
From: Max Horn <max@quendi.de>
Date: Wed, 11 Apr 2018 16:31:57 +0200
Subject: [PATCH] Fix GC bug in FuncCOMPONENTS_TRANS

The call to `NEW_PLIST` can cause a garbage collection, which would
render the `seen` pointer returned by `ResizeInitTmpTrans` invalid.

Also simplify some similar (but not buggy) code in
`FuncIMAGE_SET_TRANS_INT`

Fixes #2333
---
 src/trans.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/trans.c b/src/trans.c
index 5496e823c8..478d0d927d 100644
--- a/src/trans.c
+++ b/src/trans.c
@@ -1185,9 +1185,8 @@ Obj FuncIMAGE_SET_TRANS_INT(Obj self, Obj f, Obj n)
         return new;
     }
     else if (m < deg) {
-        pttmp = ResizeInitTmpTrans(deg);
         new = NEW_PLIST_IMM(T_PLIST_CYC, m);
-        pttmp = ADDR_TRANS4(TmpTrans);
+        pttmp = ResizeInitTmpTrans(deg);
 
         if (TNUM_OBJ(f) == T_TRANS2) {
             ptf2 = CONST_ADDR_TRANS2(f);
@@ -2900,8 +2899,8 @@ Obj FuncCOMPONENTS_TRANS(Obj self, Obj f)
         return out;
     }
 
-    seen = ResizeInitTmpTrans(deg);
     out = NEW_PLIST(T_PLIST, 1);
+    seen = ResizeInitTmpTrans(deg);
     nr = 0;
 
     if (TNUM_OBJ(f) == T_TRANS2) {