Fortran: Fix rejecting class arrays of different ranks as storage association argumen...

Fortran: Fix rejecting class arrays of different ranks as storage association argument and add un/pack_class. [PR96992]

Removing the assert in trans-expr, lead to initial strides not set
which is now fixed.  When the array needs repacking, this is done for
class arrays now, too.

Packing class arrays was done using the regular internal pack
function in the past.  But that does not use the vptr's copy
function and breaks OOP paradigms (e.g. deep copy).  The new
un-/pack_class functions use the vptr's copy functionality to
implement OOP paradigms correctly.

	PR fortran/96992

gcc/fortran/ChangeLog:

	* trans-array.cc (gfc_trans_array_bounds): Set a starting
	stride, when descriptor expects a variable for the stride.
	(gfc_trans_dummy_array_bias): Allow storage association for
	dummy class arrays, when they are not elemental.
	(gfc_conv_array_parameter): Add more general class support
	and packing for classes, too.
	* trans-array.h (gfc_conv_array_parameter): Add lbound shift
	for class arrays.
	* trans-decl.cc (gfc_build_builtin_function_decls): Add decls
	for internal_un-/pack_class.
	* trans-expr.cc (gfc_reset_vptr): Allow supplying a type-tree
	to generate the vtab from.
	(gfc_class_set_vptr): Allow supplying a class-tree to take the
	vptr from.
	(class_array_data_assign): Rename to gfc_class_array_data_assign
	and make usable from other compile units.
	(gfc_class_array_data_assign): Renamed from class_array_data_
	assign.
	(gfc_conv_derived_to_class): Remove assert to
	allow converting derived to class type arrays with assumed
	rank.  Reduce code base and use gfc_conv_array_parameter also
	for classes.
	(gfc_conv_class_to_class): Use gfc_class_data_assign.
	(gfc_conv_procedure_call): Adapt to new signature of
	gfc_conv_derived_to_class.
	* trans-io.cc (transfer_expr): Same.
	* trans-stmt.cc (trans_associate_var): Same.
	* trans.h (gfc_conv_derived_to_class): Signature changed.
	(gfc_class_array_data_assign): Made public.
	(gfor_fndecl_in_pack_class): Added declaration.
	(gfor_fndecl_in_unpack_class): Same.

libgfortran/ChangeLog:

	* Makefile.am: Add in_un-/pack_class.c to build.
	* Makefile.in: Regenerated from Makefile.am.
	* gfortran.map: Added new functions and bumped ABI.
	* libgfortran.h (GFC_CLASS_T): Added for generating class
	representation at runtime.
	* runtime/in_pack_class.c: New file.
	* runtime/in_unpack_class.c: New file.

gcc/testsuite/ChangeLog:

	* gfortran.dg/class_dummy_11.f90: New test.