2014-11-10  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/63800
	* tree-ssa-pre.c (eliminate_push_avail): Push in a way so
	we can restore the previous availability in after_dom_children.
	(eliminate_dom_walker::after_dom_children): Restore
	previous availability.

	* gcc.dg/torture/pr63800.c: New testcase.

From-SVN: r217288