PR c++/56302
	* semantics.c (finish_asm_stmt): If input constraints allow
	neither register nor memory, try maybe_constant_value to get
	a constant if possible.

	* g++.dg/torture/pr56302.C: New test.
	* g++.dg/cpp0x/constexpr-56302.C: New test.
	* c-c++-common/pr56302.c: New test.

From-SVN: r196018