http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60363
--- Comment #4 from bin.cheng <amker.cheng at gmail dot com> --- Although may be irrelavant. I found loop's latch doesn't get updated after removing the forwarder latch basic block. Previous patch only catches function remove_forwarder_block, but remove_forwarder_block_with_phi should be handled too. I will send a patch picking this up.