2005-10-01  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/16404
	PR fortran/20835
	PR fortran/20890
	PR fortran/20899
	PR fortran/20900
	PR fortran/20901
	PR fortran/20902
	* gfortran.h: Prototype for gfc_add_in_equivalence.
	* match.c (gfc_match_equivalence): Make a structure component
	an explicit,rather than a syntax, error in an equivalence
	group.  Call gfc_add_in_equivalence to add the constraints
	imposed in check_conflict.
	* resolve.c (resolve_symbol): Add constraints: No public
	structures with private-type components and no public
	procedures with private-type dummy arguments.
	(resolve_equivalence_derived): Add constraint that prevents
	a structure equivalence member from having a default
	initializer.
	(sequence_type): New static function to determine whether an
	object is default numeric, default character, non-default
	or mixed sequence. Add corresponding enum typespec.
	(resolve_equivalence): Add constraints to equivalence groups
	or their members: No more than one initialized member and
	that different types are not equivalenced for std=f95.  All
	the simple constraints have been moved to check_conflict.
	* symbol.c (check_conflict): Simple equivalence constraints
	added, including those removed from resolve_symbol.
	(gfc_add_in_equivalence): New function to interface calls
	match_equivalence to check_conflict.

2005-10-01  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/16404
	PR fortran/20835
	PR fortran/20890
	PR fortran/20899
	PR fortran/20900
	PR fortran/20901
	PR fortran/20902
	gfortran.dg/equiv_constraint_1.f90: New test.
	gfortran.dg/equiv_constraint_2.f90: New test.
	gfortran.dg/equiv_constraint_3.f90: New test.
	gfortran.dg/equiv_constraint_4.f90: New test.
	gfortran.dg/equiv_constraint_5.f90: New test.
	gfortran.dg/equiv_constraint_6.f90: New test.
	gfortran.dg/equiv_constraint_7.f90: New test.
	gfortran.dg/equiv_constraint_8.f90: New test.
	gfortran.dg/private_type_1.f90: New test.
	gfortran.dg/private_type_2.f90: New test.
	gfortran.dg/g77/980628-2.f, 980628-3.f, 980628-9.f,
	980628-10.f: Assert std=gnu to permit mixing of
	types in equivalence statements.

From-SVN: r104850