re PR fortran/18878 ([4.0 only] erronous error message on vaild USE statement)

re PR fortran/18878 ([4.0 only] erronous error message on vaild USE statement)

2005-09-09  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/18878
	* module.c (find_use_name_n): Based on original
	find_use_name. Either counts number of use names for a
	given real name or returns use name n.
	(find_use_name, number_use_names): Interfaces to the
	function find_use_name_n.
	(read_module): Add the logic and calls to these functions,
	so that mutiple reuses of the same real name are loaded.

2005-09-09  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/22304
	PR fortran/23270
	PR fortran/18870
	PR fortran/16511
	PR fortran/17917
	* gfortran.h: Move definition of BLANK_COMMON_NAME from trans-
	common.c so that it is accessible to module.c. Add common_head
	field to gfc_symbol structure. Add field for the equivalence
	name AND new attr field, in_equivalence.
	* match.c (gfc_match_common, gfc_match_equivalence): In loops
	that flag common block equivalences, emit an error if the
	common blocks are different, using sym->common_head as the
	common block identifier. Ensure that symbols that are equivalence
	associated with a common block are marked as being in_common.
	* module.c (write_blank_common): New.
	(write_common): Use unmangled common block name.
	(load_equiv): New function ported from g95.
	(read_module): Call load_equiv.
	(write_equiv): New function ported from g95. Correct
	string referencing for gfc functions. Give module
	equivalences a unique name.
	(write_module): Call write_equiv and write_blank_common.
	* primary.c (match_variable) Old gfc_match_variable, made
	static and third argument provided to indicate if parent
	namespace to be visited or not.
	(gfc_match_variable) New. Interface to match_variable.
	(gfc_match_equiv_variable) New. Interface to match_variable.
	* trans-common.c (finish_equivalences): Provide the call
	to create_common with a gfc_common_header so that
	module equivalences are made external, rather than local.
	(find_equivalences): Ensure that all members in common block
	equivalences are marked as used. This prevents the subsequent
	call to this function from making local unions.
	* trans-decl.c (gfc_generate_function_code): Move the call to
	gfc_generate_contained_functions to after the call to
	gfc_trans_common so the use-associated, contained common
	blocks produce the correct references.
	(gfc_create_module_variable): Return for equivalenced symbols
	with existing backend declaration.

2005-09-09  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/18878
	* gfortran.dg/module_double_reuse.f90: New.

2005-09-09  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/23270
	PR fortran/22304
	PR fortran/18870
	PR fortran/17917
	PR fortran/16511
	* gfortran.dg/common_equivalence_1.f: New.
	* gfortran.dg/common_equivalence_2.f: New.
	* gfortran.dg/common_equivalence_3.f: New.
	* gfortran.dg/contained_equivalence_1.f90: New.
	* gfortran.dg/module_blank_common.f90: New.
	* gfortran.dg/module_commons_1.f90: New.
	* gfortran.dg/module_equivalence_1.f90: New.
	* gfortran.dg/nested_modules_1.f90: New.
	* gfortran.dg/g77/19990905-0.f: Remove XFAIL, rearrange
	equivalences and add comment to connect the test with
	the PR.

From-SVN: r104060