* Makefile.in (tree.o): Depend on HASHTAB_H.
	* tree.c: Include hashtab.h.
	(struct type_hash): Remove next field.
	(TYPE_HASH_SIZE): Remove.
	(TYPE_HASH_INITIAL_SIZE): New define.
	(type_hash_table): Change type to htab_t.
	(type_hash_eq, type_hash_hash, print_type_hash_statistics,
	mark_hash_entry): New functions.
	(init_obstacks): Allocate type hash.
	(type_hash_lookup): Use htab functions.
	(type_hash_add, mark_type_hash): Likewise.
	(dump_tree_statistics): Call print_type_hash_statistics.

From-SVN: r32642