re PR ada/26096 (Ada bootstrap fails in g-alleve.adb)

re PR ada/26096 (Ada bootstrap fails in g-alleve.adb)

2006-02-13  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
	    Olivier Hainque  <hainque@adacore.com>
	    Eric Botcazou  <ebotcazou@adacore.com>

	* ada-tree.h: (TYPE_UNCHECKED_UNION_P): Deleted.

	* gigi.h (value_factor_p): Add prototype and description, now public.

	* decl.c (gnat_to_gnu_field): Don't attempt BLKmode to integral type
	promotion for field with rep clause if the associated size was proven
	to be in error.
	Expand comments describing attempts to use a packable type.
	(gnat_to_gnu_entity) <E_Signed_Integer_Subtype,
	E_Floating_Point_Subtype>: Inherit alias set of what we are making a
	subtype of to ensure conflicts amongst all subtypes in a hierarchy,
	necessary since these are not different types and pointers may
	actually designate any subtype in this hierarchy.
	(gnat_to_gnu_entity, case E_Record_Type): Always make fields for
	discriminants but put them into record only if not Unchecked_Union;
	pass flag to components_to_record showing Unchecked_Union.
	(make_dummy_type): Use UNION_TYPE only if Unchecked_Union and no
	components before variants; don't set TYPE_UNCHECKED_UNION_P.
	(components_to_record): New argument UNCHECKED_UNION.
	Remove special case code for Unchecked_Union and instead use main code
	with small changes.

	PR ada/26096
	(gnat_to_gnu_entity) <E_Variable>: Do not initialize the
	aligning variable with the expression being built, only its inner
	field.

	* trans.c (Handled_Sequence_Of_Statements_to_gnu): Remove call to
	emit_sequence_entry_statements.
	(emit_sequence_entry_statements, body_with_handlers_p): Delete.
	(establish_gnat_vms_condition_handler): Move before
	Subprogram_Body_to_gnu.
	(Subprogram_Body_to_gnu): On VMS, establish_gnat_vms_condition_handler
	for a subprogram if it has a foreign convention or is exported.
	(Identifier_to_gnu): Manually unshare the DECL_INITIAL tree when it is
	substituted for a CONST_DECL.
	(tree_transform, case N_Aggregate): Remove code for UNION_TYPE and pass
	Etype to assoc_to_constructor.
	(assoc_to_constructor): New argument, GNAT_ENTITY; use it to ignore
	discriminants of Unchecked_Union.
	(TARGET_ABI_OPEN_VMS): Define to 0 if not defined, so that later uses
	don't need cluttering preprocessor directives.
	(establish_gnat_vms_condition_handler): New function. Establish the GNAT
	condition handler as current in the compiled function.
	(body_with_handlers_p): New function. Tell whether a given sequence of
	statements node is attached to a package or subprogram body and involves
	exception handlers possibly nested within inner block statements.
	(emit_sequence_entry_statements): New function, to emit special
	statements on entry of sequences when necessary. Establish GNAT
	condition handler in the proper cases for VMS.
	(Handled_Sequence_Of_Statements_to_gnu): Start block code with
	emit_sequence_entry_statements.

	* utils2.c (find_common_type): If both input types are BLKmode and
	have a constant size, use the smaller one.
	(build_simple_component_ref): Also match if FIELD and NEW_FIELD are
	the same.

	* utils.c (value_factor_p): Make public, to allow uses from other gigi
	units.
	(create_type_decl): Do not set the flag DECL_IGNORED_P for dummy types.
	(convert, case UNION_TYPE): Remove special treatment for unchecked
	unions.

	PR ada/18659
	(update_pointer_to): Update variants of pointer types to
	unconstrained arrays by attaching the list of fields of the main
	variant.

From-SVN: r111030