Comment 6 for bug 984794

Is that leak related?
cardpeek$ valgrind --track-origins=yes ./cardpeek
==3428== Memcheck, a memory error detector
==3428== Copyright (C) 2002-2015, and GNU GPL'd, by Julian Seward et al.
==3428== Using Valgrind-3.11.0 and LibVEX; rerun with -h for copyright info
==3428== Command: ./cardpeek
==3428==
==3428== Conditional jump or move depends on uninitialised value(s)
==3428== at 0xBBE3F22: sse2_combine_over_u (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.32.6)
==3428== by 0xBBC953A: general_composite_rect (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.32.6)
==3428== by 0xBB7CD80: pixman_image_composite32 (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.32.6)
==3428== by 0x63C8204: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x640D190: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x63FF562: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x63FFFD4: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x6400B19: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x63BB8DE: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x63CCDF1: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x6403F55: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== by 0x63C3A2E: ??? (in /usr/lib/x86_64-linux-gnu/libcairo.so.2.11400.2)
==3428== Uninitialised value was created by a stack allocation
==3428== at 0xBBC9280: general_composite_rect (in /usr/lib/x86_64-linux-gnu/libpixman-1.so.0.32.6)