An upcoming patch exposes a bug in gimplify_modify_expr.  There, we try
not to create DECL_DEBUG_EXPR links across functions, however we don't
check that *FROM_P actually belongs to the current function before
modifying it.  This patch fixes this oversight.

gcc/

	* gimplify.c (gimplify_modify_expr): Don't create a
	DECL_DEBUG_EXPR link if *FROM_P does not belong to the current
	function.

From-SVN: r248688