Fortran: Generic processing of assumed rank objects (f202y) [PR116733]

2024-10-23  Paul Thomas  <pault@gcc.gnu.org>

gcc/fortran
	PR fortran/116733
	* array.cc : White space corrections.
	* expr.cc (gfc_check_pointer_assign): Permit assumed rank
	target with -std=f202y. Add constraints that the data pointer
	object must have rank remapping specified and the that the data
	target be contiguous.
	* gfortran.h : Add a gfc_array_ref field 'ar' to the structure
	'gfc_association_list'.
	* interface.cc (gfc_compare_actual_formal): If -Wsurprising
	is set, emit a warning if an assumed size array is passed to an
	assumed rank dummy.
	* intrinsic.cc (do_ts29113_check): Permit an assumed rank arg.
	for reshape if -std=f202y and the argument is contiguous.
	* invoke.texi : Introduce -std=f202y. Whitespace errors.
	* lang.opt : Accept -std=f202y.
	* libgfortran.h : Define GFC_STD_F202Y.
	* match.cc (gfc_match_associate): If -std=f202y an assumed rank
	selector is allowed if it is contiguous and the associate name
	has rank remapping specified.
	* options.cc (gfc_init_options): -std=f202y is equivalent to
	-std=f2023 with experimental f202y features. White space issues
	* parse.cc (parse_associate): If the selector is assumed rank,
	use the 'ar' field of the association list to build an array
	specification.
	* primary.cc (gfc_match_varspec): Do not resolve the assumed
	rank selector of a class associate name at this stage to avoid
	the rank change.
	* resolve.cc (find_array_spec): If an array_ref dimension is -1
	reset it with the rank in the object's array_spec.
	(gfc_expression_rank): Do not check dimen types for an assumed
	rank variable expression.
	(resolve_variable): Do not emit the assumed rank context error
	if the context is pointer assignment and the variable is a
	target.
	(resolve_assoc_var): Resolve the bounds and check for missing
	bounds in the rank remap of an associate name with an assumed
	rank selector. Do not correct the rank of an associate name
	with an assumed rank selector.
	(resolve_symbol): Allow the reference to an assumed rank object
	if -std-f202y is enabled and the current operation is
	EXEC_BLOCK.
	* st.cc (gfc_free_association_list): Free bounds expressions
	of the 'ar' field, if present.
	* trans-array.cc (gfc_conv_ss_startstride): If -std=f202y and
	bounds checking activated, do not apply the assertion.
	* trans-expr.cc (gfc_trans_pointer_assignment): An assumed rank
	target has its offset set to zero.
	* trans-stmt.cc (trans_associate_var): If the selector is
	assumed rank, call gfc_trans_pointer_assignment using the 'ar'
	field in the association list as the array reference for expr1.
	The data target, expr2, is a copy of the selector expression.

gcc/testsuite/
	PR fortran/116733
	* gfortran.dg/associate_3.f03: Change error message.
	* gfortran.dg/f202y/f202y.exp: Enable tests of f202y features.
	* gfortran.dg/f202y/generic_assumed_rank_1.f90: New test.
	* gfortran.dg/f202y/generic_assumed_rank_2.f90: New test.
	* gfortran.dg/f202y/generic_assumed_rank_3.f90: New test.