2007-07-01 Christopher D. Rickett <crickett@lanl.gov>

	* interface.c (gfc_compare_derived_types): Special case for comparing
	derived types across namespaces.
	(gfc_compare_types): Deal with BT_VOID.
	(compare_parameter): Use BT_VOID to accept ISO C Binding pointers.
	* trans-expr.c (gfc_conv_function_call): Remove setting parm_kind
	to SCALAR
	(gfc_conv_initializer): Deal with ISO C Binding NULL_PTR and 
	NULL_FUNPTR.
	(gfc_conv_expr): Convert expressions for ISO C Binding derived types.
	* symbol.c (gfc_set_default_type): BIND(C) variables should not be
	implicitly declared.
	(check_conflict): Add BIND(C) and check for conflicts.
	(gfc_add_explicit_interface): Whitespace.	
	(gfc_add_is_bind_c): New function.  
	(gfc_copy_attr): Use it.
	(gfc_new_symbol): Initialize ISO C Binding objects.
	(get_iso_c_binding_dt):  New function.
	(verify_bind_c_derived_type): Ditto.
	(gen_special_c_interop_ptr): Ditto.
	(add_formal_arg): Ditto.
	(gen_cptr_param): Ditto.
	(gen_fptr_param): Ditto.
	(gen_shape_param): Ditto.
	(add_proc_interface): Ditto.
	(build_formal_args): Ditto.
	(generate_isocbinding_symbol):  Ditto.
	(get_iso_c_sym):  Ditto.
	* decl.c (num_idents_on_line, has_name_equals): New variables.
	(verify_c_interop_param): New function.
	(build_sym): Finish binding labels and deal with COMMON blocks.
	(add_init_expr_to_sym): Check if the initialized expression is
	an iso_c_binding named constants
	(variable_decl): Set ISO C Binding type_spec components.
	(gfc_match_kind_spec): Check match for C interoperable kind.
	(match_char_spec): Fix comment. Chnage gfc_match_small_int
	to gfc_match_small_int_expr.  Check for C interoperable kind.
	(match_type_spec): Clear the current binding label.
	(match_attr_spec): Add DECL_IS_BIND_C.  If BIND(C) is found, use it
	to set attributes.
	(set_binding_label): New function.
	(set_com_block_bind_c): Ditto.
	(verify_c_interop): Ditto.
	(verify_com_block_vars_c_interop): Ditto.
	(verify_bind_c_sym): Ditto.
	(set_verify_bind_c_sym): Ditto.
	(set_verify_bind_c_com_block): Ditto.
	(get_bind_c_idents): Ditto.
	(gfc_match_bind_c_stmt): Ditto.
	(gfc_match_data_decl): Use num_idents_on_line.
	(match_result): Deal with right paren in BIND(C).
	(gfc_match_suffix): New function.
	(gfc_match_function_decl): Use it.  Code is re-arranged to deal with
	ISO C Binding result clauses.
	(gfc_match_subroutine):  Deal with BIND(C).
 	(gfc_match_bind_c): New function.
	(gfc_get_type_attr_spec): New function.  Code is re-arranged in and
	taken from gfc_match_derived_decl.
	(gfc_match_derived_decl): Add check for BIND(C).
	* trans-common.c: Forward declare gfc_get_common.
	(gfc_sym_mangled_common_id): Change arg from 'const char *name' to
	'gfc_common_head *com'.  Check for ISO C Binding of the common block.
	(build_common_decl): 'com->name' to 'com in SET_DECL_ASSEMBLER_NAME.
	* gfortran.h: Add GFC_MAX_BINDING_LABEL_LEN
	(bt): Add BT_VOID
	(sym_flavor): Add FL_VOID.
 	(iso_fortran_env_symbol, iso_c_binding_symbol, intmod_id): New enum
	(CInteropKind_t): New struct.
	(c_interop_kinds_table): Use it.  Declare an array of structs.
	(symbol_attribute): Add is_bind_c, is_c_interop, and is_iso_c
	bitfields.
	(gfc_typespec): Add is_c_interop; is_iso_c, and f90_type members.
	(gfc_symbol): Add from_intmod, intmod_sym_id, binding_label, and
	common_block members.
	(gfc_common_head): Add binding_label and is_bind_c members.
	(gfc_gsymbol): Add sym_name, mod_name, and binding_label members.
	Add prototypes for get_c_kind, gfc_validate_c_kind, 
	gfc_check_any_c_kind, gfc_add_is_bind_c, gfc_add_value,
	verify_c_interop, verify_c_interop_param, verify_bind_c_sym,
	verify_bind_c_derived_type, verify_com_block_vars_c_interop,
	generate_isocbinding_symbol, get_iso_c_sym, gfc_iso_c_sub_interface
	* iso-c-binding.def: New file. This file contains the definitions
	of the types provided by the Fortran 2003 ISO_C_BINDING intrinsic
	module.
	* trans-const.c (gfc_conv_constant_to_tree): Deal with C_NULL_PTR
	 or C_NULL_FUNPTR expressions.
	* expr.c (gfc_copy_expr): Add BT_VOID case.  For BT_CHARACTER, the
	ISO C Binding requires a minimum string length of 1 for '\0'.  
	* module.c (intmod_sym): New struct.
	(pointer_info): Add binding_label member.
	(write_atom): Set len to 0 for NULL pointers. Check for NULL p and *p.
	(ab_attribute): Add AB_IS_BIND_C, AB_IS_C_INTEROP and AB_IS_ISO_C.
	(attr_bits): Add "IS_BIND_C", "IS_C_INTEROP", and "IS_ISO_C".
	(mio_symbol_attribute): Deal with ISO C Binding attributes.
	(bt_types): Add "VOID".
	(mio_typespec): Deal with ISO C Binding components.
	(mio_namespace_ref): Add intmod variable. 
	(mio_symbol): Check for symbols from an intrinsic module.
	(load_commons): Check for BIND(C) common block.
	(read_module): Read binding_label and use it.
	(write_common): Add label.  Write BIND(C) info.
	(write_blank_common): Blank commons are not BIND(C).  Explicitly
	set is_bind_c=0.
	(write_symbol): Deal with binding_label.
	(sort_iso_c_rename_list): New function.
	(import_iso_c_binding_module): Ditto.
	(create_int_parameter): Add to args.
	(use_iso_fortran_env_module): Adjust to deal with iso_c_binding
	intrinsic module.
	* trans-types.c (c_interop_kinds_table): new array of structs. 
	(gfc_validate_c_kind): New function.
	(gfc_check_any_c_kind): Ditto.
	(get_real_kind_from_node): Ditto.
	(get_int_kind_from_node): Ditto.
	(get_int_kind_from_width): Ditto.
	(get_int_kind_from_minimal_width): Ditto.
	(init_c_interop_kinds): Ditto.
	(gfc_init_kinds): call init_c_interop_kinds.
	(gfc_typenode_for_spec): Adjust for BT_VOID and ISO C Binding pointers.
	Adjust handling of BT_DERIVED.
	(gfc_sym_type): Whitespace.
	(gfc_get_derived_type):  Account for iso_c_binding derived types
	* resolve.c (is_scalar_expr_ptr): New function.
	(gfc_iso_c_func_interface): Ditto.
	(resolve_function): Use gfc_iso_c_func_interface. 
	(set_name_and_label): New function.
	(gfc_iso_c_sub_interface): Ditto.
	(resolve_specific_s0): Use gfc_iso_c_sub_interface.
	(resolve_bind_c_comms): New function.
	(resolve_bind_c_derived_types): Ditto.
	(gfc_verify_binding_labels): Ditto.
	(resolve_fl_procedure): Check for ISO C interoperability.
	(resolve_symbol): Check C interoperability.
	(resolve_types): Walk the namespace.  Check COMMON blocks.
	* trans-decl.c (gfc_sym_mangled_identifier):  Prevent the mangling
	of identifiers that have an assigned binding label.
	(gfc_sym_mangled_function_id): Use the binding label rather than
	the mangled name.
	(gfc_finish_var_decl): Put variables that are BIND(C) into a common
	segment of the object file, because this is what C would do.
	(gfc_create_module_variable): Conver to proper types
	(set_tree_decl_type_code): New function.
	(generate_local_decl): Check dummy variables and derived types for
	ISO C Binding attributes.
	* match.c (gfc_match_small_int_expr): New function.
	(gfc_match_name_C): Ditto.
	(match_common_name): Deal with ISO C Binding in COMMON blocks
	* trans-io.c (transfer_expr):  Deal with C_NULL_PTR or C_NULL_FUNPTR
	expressions
	* match.h: Add prototypes for gfc_match_small_int_expr,
	gfc_match_name_C, match_common_name, set_com_block_bind_c,
	set_binding_label, set_verify_bind_c_sym,
	set_verify_bind_c_com_block, get_bind_c_idents,
	gfc_match_bind_c_stmt, gfc_match_suffix, gfc_match_bind_c,
	gfc_get_type_attr_spec
	* parse.c (decode_statement): Use gfc_match_bind_c_stmt
	(parse_derived): Init *derived_sym = NULL, and gfc_current_block
	later for valiadation.
	* primary.c (got_delim): Set ISO C Binding components of ts.
	(match_logical_constant): Ditto.
	(match_complex_constant): Ditto.
	(match_complex_constant): Ditto.
	(gfc_match_rvalue): Check for existence of at least one arg for
	C_LOC, C_FUNLOC, and C_ASSOCIATED.
	* misc.c (gfc_clear_ts): Clear ISO C Bindoing components in ts.
	(get_c_kind): New function.

2007-07-01  Christopher D. Rickett  <crickett@lanl.gov>

	* Makefile.in: Add support for iso_c_generated_procs.c and
	iso_c_binding.c.
	* Makefile.am: Ditto.
	* intrinsics/iso_c_generated_procs.c: New file containing helper
	functions.
	* intrinsics/iso_c_binding.c: Ditto.
	* intrinsics/iso_c_binding.h: New file
	* gfortran.map: Include the __iso_c_binding_c_* functions.
	* libgfortran.h: define GFC_NUM_RANK_BITS.

2007-06-23  Christopher D. Rickett  <crickett@lanl.gov>

	* bind_c_array_params.f03: New files for Fortran 2003 ISO C Binding.
	* bind_c_coms.f90: Ditto.
	* bind_c_coms_driver.c: Ditto.
	* bind_c_dts.f90: Ditto.
	* bind_c_dts_2.f03: Ditto.
	* bind_c_dts_2_driver.c: Ditto.
	* bind_c_dts_3.f03: Ditto.
	* bind_c_dts_4.f03: Ditto.
	* bind_c_dts_driver.c: Ditto.
	* bind_c_implicit_vars.f03: Ditto.
	* bind_c_procs.f03: Ditto.
	* bind_c_usage_2.f03: Ditto.
	* bind_c_usage_3.f03: Ditto.
	* bind_c_usage_5.f03: Ditto.
	* bind_c_usage_6.f03: Ditto.
	* bind_c_usage_7.f03: Ditto.
	* bind_c_vars.f90: Ditto.
	* bind_c_vars_driver.c: Ditto.
	* binding_c_table_15_1.f03: Ditto.
	* binding_label_tests.f03: Ditto.
	* binding_label_tests_10.f03: Ditto.
	* binding_label_tests_10_main.f03: Ditto.
	* binding_label_tests_11.f03: Ditto.
	* binding_label_tests_11_main.f03: Ditto.
	* binding_label_tests_12.f03: Ditto.
	* binding_label_tests_13.f03: Ditto.
	* binding_label_tests_13_main.f03: Ditto.
	* binding_label_tests_14.f03: Ditto.
	* binding_label_tests_2.f03: Ditto.
	* binding_label_tests_3.f03: Ditto.
	* binding_label_tests_4.f03: Ditto.
	* binding_label_tests_5.f03: Ditto.
	* binding_label_tests_6.f03: Ditto.
	* binding_label_tests_7.f03: Ditto.
	* binding_label_tests_8.f03: Ditto.
	* binding_label_tests_9.f03: Ditto.
	* c_assoc.f90: Ditto.
	* c_assoc_2.f03: Ditto.
	* c_f_pointer_shape_test.f90: Ditto.
	* c_f_pointer_tests.f90: Ditto.
	* c_f_tests_driver.c: Ditto.
	* c_funloc_tests.f03: Ditto.
	* c_funloc_tests_2.f03: Ditto.
	* c_funloc_tests_3.f03: Ditto.
	* c_funloc_tests_3_funcs.c: Ditto.
	* c_kind_params.f90: Ditto.
	* c_kind_tests_2.f03: Ditto.
	* c_kinds.c: Ditto.
	* c_loc_driver.c: Ditto.
	* c_loc_test.f90: Ditto.
	* c_loc_tests_2.f03: Ditto.
	* c_loc_tests_2_funcs.c: Ditto.
	* c_loc_tests_3.f03: Ditto.
	* c_loc_tests_4.f03: Ditto.
	* c_loc_tests_5.f03: Ditto.
	* c_loc_tests_6.f03: Ditto.
	* c_loc_tests_7.f03: Ditto.
	* c_loc_tests_8.f03: Ditto.
	* c_ptr_tests.f03: Ditto.
	* c_ptr_tests_10.f03: Ditto.
	* c_ptr_tests_5.f03: Ditto.
	* c_ptr_tests_7.f03: Ditto.
	* c_ptr_tests_7_driver.c: Ditto.
	* c_ptr_tests_8.f03: Ditto.
	* c_ptr_tests_8_funcs.c: Ditto.
	* c_ptr_tests_9.f03: Ditto.
	* c_ptr_tests_driver.c: Ditto.
	* c_size_t_driver.c: Ditto.
	* c_size_t_test.f03: Ditto.
	* com_block_driver.f90: Ditto.
	* global_vars_c_init.f90: Ditto.
	* global_vars_c_init_driver.c: Ditto.
	* global_vars_f90_init.f90: Ditto.
	* global_vars_f90_init_driver.c: Ditto.
	* interop_params.f03: Ditto.
	* iso_c_binding_only.f03: Ditto.
	* iso_c_binding_rename_1.f03: Ditto.
	* iso_c_binding_rename_1_driver.c: Ditto.
	* iso_c_binding_rename_2.f03: Ditto.
	* iso_c_binding_rename_2_driver.c: Ditto.
	* kind_tests_2.f03: Ditto.
	* kind_tests_3.f03: Ditto.
	* module_md5_1.f90: Ditto.
	* only_clause_main.c: Ditto.
	* print_c_kinds.f90: Ditto.
	* test_bind_c_parens.f03: Ditto.
	* test_c_assoc.c: Ditto.
	* test_com_block.f90: Ditto.
	* test_common_binding_labels.f03: Ditto.
	* test_common_binding_labels_2.f03: Ditto.
	* test_common_binding_labels_2_main.f03: Ditto.
	* test_common_binding_labels_3.f03: Ditto.
	* test_common_binding_labels_3_main.f03: Ditto.
	* test_only_clause.f90: Ditto.
	* use_iso_c_binding.f90: Ditto.
	* value_5.f90: Ditto.
	* value_test.f90: Ditto.
	* value_tests_f03.f90: Ditto.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@126185 138bc75d-0d04-0410-961f-82ee72b054a4

9 files changed, 636 insertions, 23 deletions

diff --git a/libgfortran/ChangeLog b/libgfortran/ChangeLog
index c3d2b7165af..2b880c531d8 100644
--- a/libgfortran/ChangeLog
+++ b/libgfortran/ChangeLog
@@ -1,3 +1,15 @@
+2007-07-01  Christopher D. Rickett  <crickett@lanl.gov>
+
+	* Makefile.in: Add support for iso_c_generated_procs.c and
+	iso_c_binding.c.
+	* Makefile.am: Ditto.
+	* intrinsics/iso_c_generated_procs.c: New file containing helper
+	functions.
+	* intrinsics/iso_c_binding.c: Ditto.
+	* intrinsics/iso_c_binding.h: New file
+	* gfortran.map: Include the __iso_c_binding_c_* functions.
+	* libgfortran.h: define GFC_NUM_RANK_BITS.
+
 2007-07-01  Janne Blomqvist  <jb@gcc.gnu.org>
 
 	PR fortran/32239
diff --git a/libgfortran/Makefile.am b/libgfortran/Makefile.am
index 0e745300172..ba81c75f238 100644
--- a/libgfortran/Makefile.am
+++ b/libgfortran/Makefile.am
@@ -71,9 +71,11 @@ intrinsics/getcwd.c \
 intrinsics/getlog.c \
 intrinsics/getXid.c \
 intrinsics/hostnm.c \
-intrinsics/kill.c \
 intrinsics/ierrno.c \
 intrinsics/ishftc.c \
+intrinsics/iso_c_generated_procs.c \
+intrinsics/iso_c_binding.c \
+intrinsics/kill.c \
 intrinsics/link.c \
 intrinsics/malloc.c \
 intrinsics/mvbits.c \
diff --git a/libgfortran/Makefile.in b/libgfortran/Makefile.in
index c2acb1353a7..5d97b903ddc 100644
--- a/libgfortran/Makefile.in
+++ b/libgfortran/Makefile.in
@@ -194,7 +194,8 @@ am__objects_32 = associated.lo abort.lo access.lo args.lo \
 	reshape_generic.lo reshape_packed.lo selected_int_kind.lo \
 	selected_real_kind.lo stat.lo symlnk.lo system_clock.lo \
 	time.lo transpose_generic.lo umask.lo unlink.lo \
-	unpack_generic.lo in_pack_generic.lo in_unpack_generic.lo
+	unpack_generic.lo in_pack_generic.lo in_unpack_generic.lo \
+	iso_c_generated_procs.lo iso_c_binding.lo
 am__objects_33 =
 am__objects_34 = _abs_c4.lo _abs_c8.lo _abs_c10.lo _abs_c16.lo \
 	_abs_i4.lo _abs_i8.lo _abs_i16.lo _abs_r4.lo _abs_r8.lo \
@@ -456,9 +457,11 @@ intrinsics/getcwd.c \
 intrinsics/getlog.c \
 intrinsics/getXid.c \
 intrinsics/hostnm.c \
-intrinsics/kill.c \
 intrinsics/ierrno.c \
 intrinsics/ishftc.c \
+intrinsics/iso_c_generated_procs.c \
+intrinsics/iso_c_binding.c \
+intrinsics/kill.c \
 intrinsics/link.c \
 intrinsics/malloc.c \
 intrinsics/mvbits.c \
@@ -4295,6 +4298,15 @@ ishftc.lo: intrinsics/ishftc.c
 @AMDEP_TRUE@@am__fastdepCC_FALSE@	DEPDIR=$(DEPDIR) $(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
 @am__fastdepCC_FALSE@	$(LIBTOOL) --tag=CC --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o ishftc.lo `test -f 'intrinsics/ishftc.c' || echo '$(srcdir)/'`intrinsics/ishftc.c
 
+iso_c_generated_procs.lo: intrinsics/iso_c_generated_procs.c
+	$(LIBTOOL) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o iso_c_generated_procs.lo `test -f 'intrinsics/iso_c_generated_procs.c' || echo '$(srcdir)/'`intrinsics/iso_c_generated_procs.c
+
+iso_c_binding.lo: intrinsics/iso_c_binding.c
+	$(LIBTOOL) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o iso_c_binding.lo `test -f 'intrinsics/iso_c_binding.c' || echo '$(srcdir)/'`intrinsics/iso_c_binding.c
+
+kill.lo: intrinsics/kill.c
+	$(LIBTOOL) --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -c -o kill.lo `test -f 'intrinsics/kill.c' || echo '$(srcdir)/'`intrinsics/kill.c
+
 link.lo: intrinsics/link.c
 @am__fastdepCC_TRUE@	if $(LIBTOOL) --tag=CC --mode=compile $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS) -MT link.lo -MD -MP -MF "$(DEPDIR)/link.Tpo" -c -o link.lo `test -f 'intrinsics/link.c' || echo '$(srcdir)/'`intrinsics/link.c; \
 @am__fastdepCC_TRUE@	then mv -f "$(DEPDIR)/link.Tpo" "$(DEPDIR)/link.Plo"; else rm -f "$(DEPDIR)/link.Tpo"; exit 1; fi
diff --git a/libgfortran/gfortran.map b/libgfortran/gfortran.map
index 6aebef3cb82..71c809a11f5 100644
--- a/libgfortran/gfortran.map
+++ b/libgfortran/gfortran.map
@@ -1003,6 +1003,23 @@ GFORTRAN_1.0 {
     _gfortran_unpack0_char;
     _gfortran_unpack1;
     _gfortran_unpack1_char;
+    __iso_c_binding_c_associated_1;
+    __iso_c_binding_c_associated_2;
+    __iso_c_binding_c_f_pointer;
+    __iso_c_binding_c_f_pointer_d0;
+    __iso_c_binding_c_f_pointer_i1;
+    __iso_c_binding_c_f_pointer_i2;
+    __iso_c_binding_c_f_pointer_i4;
+    __iso_c_binding_c_f_pointer_i8;
+    __iso_c_binding_c_f_pointer_i16;
+    __iso_c_binding_c_f_pointer_r4;
+    __iso_c_binding_c_f_pointer_r8;
+    __iso_c_binding_c_f_pointer_r10;
+    __iso_c_binding_c_f_pointer_r16;
+    __iso_c_binding_c_f_pointer_u0;
+    __iso_c_binding_c_f_procpointer;
+    __iso_c_binding_c_funloc;
+    __iso_c_binding_c_loc;
   local:
     *;
 };
diff --git a/libgfortran/intrinsics/iso_c_binding.c b/libgfortran/intrinsics/iso_c_binding.c
new file mode 100644
index 00000000000..33575475aa6
--- /dev/null
+++ b/libgfortran/intrinsics/iso_c_binding.c
@@ -0,0 +1,249 @@
+/* Implementation of the ISO_C_BINDING library helper functions.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   Contributed by Christopher Rickett.
+
+This file is part of the GNU Fortran 95 runtime library (libgfortran).
+
+Libgfortran is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+Libgfortran is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public
+License along with libgfortran; see the file COPYING.  If not,
+write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+
+/* Implement the functions and subroutines provided by the intrinsic
+   iso_c_binding module.  */
+
+#include <stdlib.h>
+
+#include "libgfortran.h"
+#include "iso_c_binding.h"
+
+
+/* Set the fields of a Fortran pointer descriptor to point to the
+   given C address.  It uses c_f_pointer_u0 for the common
+   fields, and will set up the information necessary if this C address
+   is to an array (i.e., offset, type, element size).  The parameter
+   c_ptr_in represents the C address to have Fortran point to.  The
+   parameter f_ptr_out is the Fortran pointer to associate with the C
+   address.  The parameter shape is a one-dimensional array of integers
+   specifying the upper bound(s) of the array pointed to by the given C
+   address, if applicable.  The shape parameter is optional in Fortran,
+   which will cause it to come in here as NULL.  The parameter type is
+   the type of the data being pointed to (i.e.,libgfortran.h). The
+   elem_size parameter is the size, in bytes, of the data element being
+   pointed to.  If the address is for an array, then the size needs to
+   be the size of a single element (i.e., for an array of doubles, it
+   needs to be the number of bytes for the size of one double).  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer) (void *c_ptr_in,
+                                    gfc_array_void *f_ptr_out,
+                                    const array_t *shape,
+                                    int type, int elemSize)
+{
+  if (shape != NULL)
+    {
+      f_ptr_out->offset = 0;
+
+      /* Set the necessary dtype field for all pointers.  */
+      f_ptr_out->dtype = 0;
+
+      /* Put in the element size.  */
+      f_ptr_out->dtype = f_ptr_out->dtype | (elemSize << GFC_DTYPE_SIZE_SHIFT);
+
+      /* Set the data type (e.g., GFC_DTYPE_INTEGER).  */
+      f_ptr_out->dtype = f_ptr_out->dtype | (type << GFC_DTYPE_TYPE_SHIFT);
+    }
+  
+  /* Use the generic version of c_f_pointer to set common fields.  */
+  ISO_C_BINDING_PREFIX (c_f_pointer_u0) (c_ptr_in, f_ptr_out, shape);
+}
+
+
+/* A generic function to set the common fields of all descriptors, no
+   matter whether it's to a scalar or an array.  Fields set are: data,
+   and if appropriate, rank, offset, dim[*].lbound, dim[*].ubound, and
+   dim[*].stride.  Parameter shape is a rank 1 array of integers
+   containing the upper bound of each dimension of what f_ptr_out
+   points to.  The length of this array must be EXACTLY the rank of
+   what f_ptr_out points to, as required by the draft (J3/04-007).  If
+   f_ptr_out points to a scalar, then this parameter will be NULL.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_u0) (void *c_ptr_in,
+                                       gfc_array_void *f_ptr_out,
+                                       const array_t *shape)
+{
+  int i = 0;
+  int shapeSize = 0;
+
+  GFC_DESCRIPTOR_DATA (f_ptr_out) = c_ptr_in;
+
+  if (shape != NULL)
+    {
+      f_ptr_out->offset = 0;
+      shapeSize = 0;
+      
+      /* shape's length (rank of the output array) */
+      shapeSize = shape->dim[0].ubound + 1 - shape->dim[0].lbound;
+      for (i = 0; i < shapeSize; i++)
+        {
+          /* Lower bound is 1, as specified by the draft.  */
+          f_ptr_out->dim[i].lbound = 1;
+          f_ptr_out->dim[i].ubound = ((int *) (shape->data))[i];
+        }
+
+      /* Set the offset and strides.
+         offset is (sum of (dim[i].lbound * dim[i].stride) for all
+         dims) the -1 means we'll back the data pointer up that much
+         perhaps we could just realign the data pointer and not change
+         the offset?  */
+      f_ptr_out->dim[0].stride = 1;
+      f_ptr_out->offset = f_ptr_out->dim[0].lbound * f_ptr_out->dim[0].stride;
+      for (i = 1; i < shapeSize; i++)
+        {
+          f_ptr_out->dim[i].stride = (f_ptr_out->dim[i-1].ubound + 1)
+            - f_ptr_out->dim[i-1].lbound;
+          f_ptr_out->offset += f_ptr_out->dim[i].lbound
+            * f_ptr_out->dim[i].stride;
+        }
+
+      f_ptr_out->offset *= -1;
+
+      /* All we know is the rank, so set it, leaving the rest alone.
+         Make NO assumptions about the state of dtype coming in!  If we
+         shift right by TYPE_SHIFT bits we'll throw away the existing
+         rank.  Then, shift left by the same number to shift in zeros
+         and or with the new rank.  */
+      f_ptr_out->dtype = ((f_ptr_out->dtype >> GFC_DTYPE_TYPE_SHIFT)
+                           << GFC_DTYPE_TYPE_SHIFT) | shapeSize;
+    }
+}
+
+
+/* Sets the descriptor fields for a Fortran pointer to a derived type,
+   using c_f_pointer_u0 for the majority of the work.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_d0) (void *c_ptr_in,
+                                       gfc_array_void *f_ptr_out,
+                                       const array_t *shape)
+{
+  /* Set the common fields.  */
+  ISO_C_BINDING_PREFIX (c_f_pointer_u0) (c_ptr_in, f_ptr_out, shape);
+
+  /* Preserve the size and rank bits, but reset the type.  */
+  if (shape != NULL)
+    {
+      f_ptr_out->dtype = f_ptr_out->dtype & (~GFC_DTYPE_TYPE_MASK);
+      f_ptr_out->dtype = f_ptr_out->dtype
+			 | (GFC_DTYPE_DERIVED << GFC_DTYPE_TYPE_SHIFT);
+    }
+}
+
+
+/* This function will change, once there is an actual f90 type for the
+   procedure pointer.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_procpointer) (void *c_ptr_in,
+                                        gfc_array_void *f_ptr_out)
+{
+  GFC_DESCRIPTOR_DATA(f_ptr_out) = c_ptr_in;
+}
+
+
+/* Test if the given c_ptr is associated or not.  This function is
+   called if the user only supplied one c_ptr parameter to the
+   c_associated function.  The second argument is optional, and the
+   Fortran compiler will resolve the function to this version if only
+   one arg was given.  Associated here simply means whether or not the
+   c_ptr is NULL or not.  */
+
+GFC_LOGICAL_4
+ISO_C_BINDING_PREFIX (c_associated_1) (void *c_ptr_in_1)
+{
+  if (c_ptr_in_1 != NULL)
+    return 1;
+  else
+    return 0;
+}
+
+
+/* Test if the two c_ptr arguments are associated with one another.
+   This version of the c_associated function is called if the user
+   supplied two c_ptr args in the Fortran source.  According to the
+   draft standard (J3/04-007), if c_ptr_in_1 is NULL, the two pointers
+   are NOT associated.  If c_ptr_in_1 is non-NULL and it is not equal
+   to c_ptr_in_2, then either c_ptr_in_2 is NULL or is associated with
+   another address; either way, the two pointers are not associated
+   with each other then.  */
+
+GFC_LOGICAL_4
+ISO_C_BINDING_PREFIX (c_associated_2) (void *c_ptr_in_1, void *c_ptr_in_2)
+{
+  /* Since we have the second arg, if it doesn't equal the first,
+     return false; true otherwise.  However, if the first one is null,
+     then return false; otherwise compare the two ptrs for equality.  */
+  if (c_ptr_in_1 == NULL)
+    return 0;
+  else if (c_ptr_in_1 != c_ptr_in_2)
+    return 0;
+  else
+    return 1;
+}
+
+
+/* Return the C address of the given Fortran allocatable object.  */
+
+void *
+ISO_C_BINDING_PREFIX (c_loc) (void *f90_obj)
+{
+  if (f90_obj == NULL)
+    {
+      runtime_error ("C_LOC: Attempt to get C address for Fortran object"
+                     " that has not been allocated or associated");
+      abort ();
+    }
+   
+  /* The "C" address should be the address of the object in Fortran.  */
+  return f90_obj;
+}
+
+
+/*  Return the C address of the given Fortran procedure.  This
+    routine is expected to return a derived type of type C_FUNPTR,
+    which represents the C address of the given Fortran object.  */
+
+void *
+ISO_C_BINDING_PREFIX (c_funloc) (void *f90_obj)
+{
+  if (f90_obj == NULL)
+    {
+      runtime_error ("C_LOC: Attempt to get C address for Fortran object"
+                     " that has not been allocated or associated");
+      abort ();
+    }
+
+  /* The "C" address should be the address of the object in Fortran.  */
+  return f90_obj;
+}
diff --git a/libgfortran/intrinsics/iso_c_binding.h b/libgfortran/intrinsics/iso_c_binding.h
new file mode 100644
index 00000000000..afd85529e9d
--- /dev/null
+++ b/libgfortran/intrinsics/iso_c_binding.h
@@ -0,0 +1,70 @@
+/* Copyright (C) 2007 Free Software Foundation, Inc.
+   Contributed by Christopher Rickett.
+
+This file is part of the GNU Fortran 95 runtime library (libgfortran).
+
+Libgfortran is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+Libgfortran is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with Libgfortran; see the file COPYING.  If not, write to
+the Free Software Foundation, 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+
+/* Declarations for ISO_C_BINDING library helper functions.  */
+
+#ifndef GFOR_ISO_C_BINDING_H
+#define GFOR_ISO_C_BINDING_H
+
+#include "libgfortran.h"
+
+typedef struct c_ptr
+{
+  void *c_address;
+}
+c_ptr_t;
+
+typedef struct c_funptr
+{
+  void *c_address;
+}
+c_funptr_t;
+
+#define ISO_C_BINDING_PREFIX(a) __iso_c_binding_##a
+
+void ISO_C_BINDING_PREFIX(c_f_pointer)(void *, gfc_array_void *,
+				       const array_t *, int, int);
+
+/* The second param here may change, once procedure pointers are
+   implemented.  */
+void ISO_C_BINDING_PREFIX(c_f_procpointer) (void *, gfc_array_void *);
+
+GFC_LOGICAL_4 ISO_C_BINDING_PREFIX(c_associated_1) (void *);
+GFC_LOGICAL_4 ISO_C_BINDING_PREFIX(c_associated_2) (void *, void *);
+
+void ISO_C_BINDING_PREFIX(c_f_pointer_u0) (void *, gfc_array_void *,
+					   const array_t *);
+void ISO_C_BINDING_PREFIX(c_f_pointer_d0) (void *, gfc_array_void *,
+					   const array_t *);
+
+void *ISO_C_BINDING_PREFIX(c_loc) (void *);
+void *ISO_C_BINDING_PREFIX(c_funloc) (void *);
+
+#endif
diff --git a/libgfortran/intrinsics/iso_c_generated_procs.c b/libgfortran/intrinsics/iso_c_generated_procs.c
new file mode 100644
index 00000000000..f60b264dba6
--- /dev/null
+++ b/libgfortran/intrinsics/iso_c_generated_procs.c
@@ -0,0 +1,264 @@
+/* Implementation of the ISO_C_BINDING library helper generated functions.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   Contributed by Christopher Rickett.
+
+This file is part of the GNU Fortran 95 runtime library (libgfortran).
+
+Libgfortran is free software; you can redistribute it and/or
+modify it under the terms of the GNU General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+In addition to the permissions in the GNU General Public License, the
+Free Software Foundation gives you unlimited permission to link the
+compiled version of this file into combinations with other programs,
+and to distribute those combinations without any restriction coming
+from the use of this file.  (The General Public License restrictions
+do apply in other respects; for example, they cover modification of
+the file, and distribution when not linked into a combine
+executable.)
+
+Libgfortran is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public
+License along with libgfortran; see the file COPYING.  If not,
+write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+Boston, MA 02110-1301, USA.  */
+
+
+#include "libgfortran.h"
+#include "iso_c_binding.h"
+
+
+/* TODO: This file needs to be finished so that a function is provided
+   for all possible type/kind combinations!  */
+
+#ifdef HAVE_GFC_INTEGER_1
+void ISO_C_BINDING_PREFIX (c_f_pointer_i1) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_INTEGER_2
+void ISO_C_BINDING_PREFIX (c_f_pointer_i2) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_INTEGER_4
+void ISO_C_BINDING_PREFIX (c_f_pointer_i4) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_INTEGER_8
+void ISO_C_BINDING_PREFIX (c_f_pointer_i8) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_INTEGER_16
+void ISO_C_BINDING_PREFIX (c_f_pointer_i16) (void *, gfc_array_void *,
+					     const array_t *);
+#endif
+
+#ifdef HAVE_GFC_REAL_4
+void ISO_C_BINDING_PREFIX (c_f_pointer_r4) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_REAL_8
+void ISO_C_BINDING_PREFIX (c_f_pointer_r8) (void *, gfc_array_void *,
+					    const array_t *);
+#endif
+
+#ifdef HAVE_GFC_REAL_10
+void ISO_C_BINDING_PREFIX (c_f_pointer_r10) (void *, gfc_array_void *,
+					     const array_t *);
+#endif
+#ifdef HAVE_GFC_REAL_16
+void ISO_C_BINDING_PREFIX (c_f_pointer_r16) (void *, gfc_array_void *,
+					     const array_t *);
+#endif
+
+
+#ifdef HAVE_GFC_INTEGER_1
+/* Set the given Fortran pointer, 'f_ptr_out', to point to the given C
+   address, 'c_ptr_in'.  The Fortran pointer is of type integer and
+   kind=1.  The function c_f_pointer is used to set up the pointer
+   descriptor.  shape is a one-dimensional array of integers
+   specifying the upper bounds of the array pointed to by the given C
+   address, if applicable.  'shape' is an optional parameter in
+   Fortran, so if the user does not provide it, it will come in here
+   as NULL.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_i1) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an integer(kind=1).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_INTEGER,
+				      (int) sizeof (GFC_INTEGER_1));
+}
+#endif
+
+
+#ifdef HAVE_GFC_INTEGER_2
+/* Set the given Fortran pointer, 'f_ptr_out', to point to the given C
+   address, 'c_ptr_in'.  The Fortran pointer is of type integer and
+   kind=2.  The function c_f_pointer is used to set up the pointer
+   descriptor.  shape is a one-dimensional array of integers
+   specifying the upper bounds of the array pointed to by the given C
+   address, if applicable.  'shape' is an optional parameter in
+   Fortran, so if the user does not provide it, it will come in here
+   as NULL.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_i2) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an integer(kind=2).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_INTEGER,
+				      (int) sizeof (GFC_INTEGER_2));
+}
+#endif
+
+
+#ifdef HAVE_GFC_INTEGER_4
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type integer and
+   kind=4.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_i4) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an integer(kind=4).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_INTEGER,
+				      (int) sizeof (GFC_INTEGER_4));
+}
+#endif
+
+
+#ifdef HAVE_GFC_INTEGER_8
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type integer and
+   kind=8.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_i8) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an integer(kind=8).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_INTEGER,
+				      (int) sizeof (GFC_INTEGER_8));
+}
+#endif
+
+
+#ifdef HAVE_GFC_INTEGER_16
+/* Set the given Fortran pointer, 'f_ptr_out', to point to the given C
+   address, 'c_ptr_in'.  The Fortran pointer is of type integer and
+   kind=16.  The function c_f_pointer is used to set up the pointer
+   descriptor.  shape is a one-dimensional array of integers
+   specifying the upper bounds of the array pointed to by the given C
+   address, if applicable.  'shape' is an optional parameter in
+   Fortran, so if the user does not provide it, it will come in here
+   as NULL.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_i16) (void *c_ptr_in,
+					gfc_array_void *f_ptr_out,
+					const array_t *shape)
+{
+  /* Here we have an integer(kind=16).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_INTEGER,
+				      (int) sizeof (GFC_INTEGER_16));
+}
+#endif
+
+
+#ifdef HAVE_GFC_REAL_4
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type real and
+   kind=4.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_r4) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an real(kind=4).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_REAL,
+				      (int) sizeof (GFC_REAL_4));
+}
+#endif
+
+
+#ifdef HAVE_GFC_REAL_8
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type real and
+   kind=8.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_r8) (void *c_ptr_in,
+				       gfc_array_void *f_ptr_out,
+				       const array_t *shape)
+{
+  /* Here we have an real(kind=8).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_REAL,
+				      (int) sizeof (GFC_REAL_8));
+}
+#endif
+
+
+#ifdef HAVE_GFC_REAL_10
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type real and
+   kind=10.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_r10) (void *c_ptr_in,
+					gfc_array_void *f_ptr_out,
+					const array_t *shape)
+{
+  /* Here we have an real(kind=10).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_REAL,
+				      (int) sizeof (GFC_REAL_10));
+}
+#endif
+
+
+#ifdef HAVE_GFC_REAL_16
+/* Set the given Fortran pointer, f_ptr_out, to point to the given C
+   address, c_ptr_in.  The Fortran pointer is of type real and
+   kind=16.  The function c_f_pointer is used to set up the pointer
+   descriptor.  */
+
+void
+ISO_C_BINDING_PREFIX (c_f_pointer_r16) (void *c_ptr_in,
+					gfc_array_void *f_ptr_out,
+					const array_t *shape)
+{
+  /* Here we have an real(kind=16).  */
+  ISO_C_BINDING_PREFIX (c_f_pointer) (c_ptr_in, f_ptr_out, shape,
+				      (int) GFC_DTYPE_REAL,
+				      (int) sizeof (GFC_REAL_16));
+}
+#endif
diff --git a/libgfortran/io/unit.c b/libgfortran/io/unit.c
index fac67bdaf7e..9297af08521 100644
--- a/libgfortran/io/unit.c
+++ b/libgfortran/io/unit.c
@@ -690,26 +690,11 @@ update_position (gfc_unit *u)
    must free memory allocated for the filename string.  */
 
 char *
-filename_from_unit (int n)
+filename_from_unit (int unit_number)
 {
   char *filename;
-  gfc_unit *u;
-  int c;
-
-  /* Find the unit.  */
-  u = unit_root;
-  while (u != NULL)
-    {
-      c = compare (n, u->unit_number);
-      if (c < 0)
-	u = u->left;
-      if (c > 0)
-	u = u->right;
-      if (c == 0)
-	break;
-    }
-
-  /* Get the filename.  */
+  gfc_unit *u = NULL;
+  u = find_unit (unit_number);
   if (u != NULL)
     {
       filename = (char *) get_mem (u->file_len + 1);
@@ -718,5 +703,4 @@ filename_from_unit (int n)
     }
   else
     return (char *) NULL;
-}
-
+}
\ No newline at end of file
diff --git a/libgfortran/libgfortran.h b/libgfortran/libgfortran.h
index e0801a14d16..f73594dc4d7 100644
--- a/libgfortran/libgfortran.h
+++ b/libgfortran/libgfortran.h
@@ -321,6 +321,9 @@ typedef GFC_ARRAY_DESCRIPTOR (GFC_MAX_DIMENSIONS, GFC_LOGICAL_16) gfc_array_l16;
 #define GFC_DTYPE_TYPE_MASK 0x38
 #define GFC_DTYPE_SIZE_SHIFT 6
 
+/* added for f03.  --Rickett, 02.28.06 */
+#define GFC_NUM_RANK_BITS 3
+
 enum
 {
   GFC_DTYPE_UNKNOWN = 0,