Perforate fnspec strings

Perforate fnspec strings

gcc/ChangeLog:

2020-10-02  Jan Hubicka  <hubicka@ucw.cz>

	* attr-fnspec.h: Update documentation.
	(attr_fnsec::return_desc_size): Set to 2
	(attr_fnsec::arg_desc_size): Set to 2
	* builtin-attrs.def (STR1): Update fnspec.
	* internal-fn.def (UBSAN_NULL): Update fnspec.
	(UBSAN_VPTR): Update fnspec.
	(UBSAN_PTR): Update fnspec.
	(ASAN_CHECK): Update fnspec.
	(GOACC_DIM_SIZE): Remove fnspec.
	(GOACC_DIM_POS): Remove fnspec.
	* tree-ssa-alias.c (attr_fnspec::verify): Update verification.

gcc/fortran/ChangeLog:

2020-10-02  Jan Hubicka  <hubicka@ucw.cz>

	* trans-decl.c (gfc_build_library_function_decl_with_spec): Verify
	fnspec.
	(gfc_build_intrinsic_function_decls): Update fnspecs.
	(gfc_build_builtin_function_decls): Update fnspecs.
	* trans-io.c (gfc_build_io_library_fndecls): Update fnspecs.
	* trans-types.c (create_fn_spec): Update fnspecs.