2006-10-21  Richard Guenther  <rguenther@suse.de>

	PR middle-end/26898
	* fold-const.c (fold_comparison): Fold signed comparisons
	of the form X +- C1 CMP Y +- C2.

	* gcc.dg/torture/pr26898-1.c: New testcase.
	* gcc.dg/torture/pr26898-2.c: Likewise.

From-SVN: r117931