Fortran: Assumed and explicit size class arrays [PR46691/99819].

Fortran: Assumed and explicit size class arrays [PR46691/99819].

2021-05-06  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran/ChangeLog

	PR fortran/46691
	PR fortran/99819
	* class.c (gfc_build_class_symbol): Remove the error that
	disables assumed size class arrays. Class array types that are
	not deferred shape or assumed rank are given a unique name and
	placed in the procedure namespace.
	* trans-array.c (gfc_trans_g77_array): Obtain the data pointer
	for class arrays.
	(gfc_trans_dummy_array_bias): Suppress the runtime error for
	extent violations in explicit shape class arrays because it
	always fails.
	* trans-expr.c (gfc_conv_procedure_call): Handle assumed size
	class actual arguments passed to non-descriptor formal args by
	using the data pointer, stored as the symbol's backend decl.

gcc/testsuite/ChangeLog

	PR fortran/46691
	PR fortran/99819
	* gfortran.dg/class_dummy_6.f90: New test.
	* gfortran.dg/class_dummy_7.f90: New test.

(cherry picked from commit a2c593009fef1564dbef2237ee71e9fd08f5361e)