https://gcc.gnu.org/ml/gcc-patches/2017-10/msg00846.html
	* tree-core.h (tree_contains_struct): Make bool.
	* tree.c (tree_contains_struct): Likewise.
	* tree.h (MARK_TS_BASE): Remove do ... while (0) idiom.
	(MARK_TS_TYPED, MARK_TS_COMMON, MARK_TS_TYPE_COMMON,
	MARK_TS_TYPE_WITH_LANG_SPECIFIC, MARK_TS_DECL_MINIMAL,
	MARK_TS_DECL_COMMON, MARK_TS_DECL_WRTL, MARK_TS_DECL_WITH_VIS,
	MARK_TS_DECL_NON_COMMON): Likewise, use comma operator.

From-SVN: r253723