You are right, I tried the nightly 1.2 build and this problem does not occur. I have attached valgrind trace for the 1.12 build in any case. ==10687== Memcheck, a memory error detector ==10687== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al. ==10687== Using Valgrind-3.6.1 and LibVEX...