2013-02-18  Richard Biener  <rguenther@suse.de>

	PR middle-end/56350
	* cfghooks.c (merge_blocks): If we merge a latch into another
	block adjust references to it.
	* cfgloop.c (flow_loops_find): Reset latch before recomputing it.
	(verify_loop_structure): Verify that a recorded latch is in fact
	a latch.

	* gcc.dg/torture/pr56350.c: New testcase.

From-SVN: r196118