Rare failure to build caused by Launchpad

Today as I was building a new Git checkout from GIMP repository, one of the build failed (Trusty i386), as all the other builds went fine for amd64 Trusty, Vivid and Willy.

Looking at the cause of the failure I couldn't see an explanation for a reportedly missing file. As well this package is not build in parallel mode. You may be interested in the failure ?

mkdir -p `dirname 12/gimp-menu-left.png`; /usr/bin/gegl -x "<gegl> <node operation='gegl:invert-gamma'></node> <node operation='gegl:load'> <params> <param name='path'>/«BUILDDIR»/gimp-2.9.2.565+git20160305.8b4455ba/icons/Symbolic/12/gimp-menu-left.png</param> </params> </node> </gegl>" -o 12/gimp-menu-left.png
cp: cannot create regular file ‘12/gimp-default-colors.png’: No such file or directory
make[4]: *** [12/gimp-default-colors.png] Error 1

Full log at https://launchpadlibrarian.net/246204580/buildlog_ubuntu-trusty-i386.gimp_2.9.2.565+git20160305.8b4455ba-1pmo1~trusty_BUILDING.txt.gz

Relaunching the build did work as expected.