http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52911
--- Comment #11 from Mikael Pettersson <mikpe at it dot uu.se> 2013-01-21 22:52:18 UTC --- This ICE was fixed for 4.8 by Alan Modra's "PR53914, rs6000 constraints and reload queries" fix in r189801. The ICE described in http://gcc.gnu.org/ml/gcc/2012-07/msg00142.html and the linked-to Red Hat bugzilla entry looks exactly like this PR's ICE. The patch is localized to the rs6000 backend, but it's quite big so I would not be comfortable backporting it en masse to 4.7 branch.