2007-04-27  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/31715
	* tree-ssa-ccp.c (maybe_fold_offset_to_array_ref): Make
	sure to do computation on the offset in an appropriate
	signed type.

	* gcc.dg/Warray-bounds-4.c: New testcase.

From-SVN: r124216