2011-04-26  Richard Guenther  <rguenther@suse.de>

	PR middle-end/48694
	* tree.h (OEP_CONSTANT_ADDRESS_OF): New operand_equal_flag.
	* fold-const.c (operand_equal_p): For TREE_CONSTANT ADDR_EXPRs
	compare the operands with OEP_CONSTANT_ADDRESS_OF.  Treat
	trees with TREE_SIDE_EFFECTS equal when OEP_CONSTANT_ADDRESS_OF
	is set.

	* gcc.dg/torture/pr48694-1.c: New testcase.
	* gcc.dg/torture/pr48694-2.c: Likewise.

From-SVN: r172954