http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58640
--- Comment #3 from Jeffrey A. Law <law at redhat dot com> --- May be related to trying to thread through 2 loop headers. ie,we're starting the jump thread path outside any loops. On the jump thread path we find a loop header, then the loop header for a nested loop. The updating code knows how to handle threading through a single loop header in a specific set of conditions, but I'm pretty sure it's not prepared to handle threading through a nest of headers. I'm still investigating.
