* builtins.c (expand_builtin_strncpy): Use integer_zerop instead
	of compare_tree_int.
	(expand_builtin_strncat): Likewise.
	* c-decl.c (finish_struct): Use tree_low_cst.
	* tree.h (compare_tree_int): Arg is unsigned HOST_WIDE_INT.
	* tree.c (compare_tree_int): Likewise.

From-SVN: r49222