2014-12-15  Richard Biener  <rguenther@suse.de>

	PR middle-end/64246
	* cfgloop.c (mark_loop_for_removal): Make safe against multiple
	invocations on the same loop.

	* gnat.dg/opt46.adb: New testcase.
	* gnat.dg/opt46.ads: Likewise.
	* gnat.dg/opt46_pkg.adb: Likewise.
	* gnat.dg/opt46_pkg.ads: Likewise.

From-SVN: r218746