* crtstuff.c (__dso_handle): Declare.

	(__cxa_finalize): Likewise.
	(do_global_dtors_aux): Call __cxa_finalize if __dso_handle is
	non-NULL.

	* invoke.texi: Document -fuse-cxa-atexit.

	* tree.h (ptr_type_node): Document.
	(const_ptr_type_node): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@30989 138bc75d-0d04-0410-961f-82ee72b054a4