2015-07-02 Paul Thomas <pault@gcc.gnu.org>

	PR fortran/52846
	* decl.c (get_proc_name): Make a partially populated interface
	symbol to carry the characteristics of a module procedure and
	its result.
	(variable_decl): Declarations of dummies or results in the
	abreviated form of module procedure is an error.
	(gfc_match_import): IMPORT is not permitted in the interface
	declaration of module procedures.
	(match_attr_spec): Submodule variables have implicit save
	attribute for F2008 onwards.
	(gfc_match_prefix): Add 'module' as the a prefix and set the
	module_procedure attribute.
	(gfc_match_formal_arglist): For a module procedure keep the
	interface formal_arglist from the interface, match new the
	formal arguments and then compare the number and names of each.
	(gfc_match_procedure): Add case COMP_SUBMODULE.
	(gfc_match_function_decl, gfc_match_subroutine_decl): Set the
	module_procedure attribute.
	(gfc_match_entry, gfc_match_end):  Add case COMP_SUBMODULE. If
	attr abr_modproc_decl is set, switch the message accordingly
	for subroutines and functions.
	(gfc_match_submod_proc): New function to match the abbreviated
	style of submodule declaration.
	* gfortran.h : Add ST_SUBMODULE and ST_END_SUBMODULE. Add the
	attribute bits 'used_in_submodule' and 'module_procedure'. Add
	the bit field 'abr_modproc_decl' to gfc_symbol. Add prototypes
	for 'gfc_copy_dummy_sym', 'gfc_check_dummy_characteristics' and
	'gfc_check_result_characteristics'.
	* interface.c : Add the prefix 'gfc_' to the names of functions
	'check_dummy(result)_characteristics' and all their references.
	* match.h : Add prototype for 'gfc_match_submod_proc' and
	'gfc_match_submodule'.
	(check_sym_interfaces): A module procedure is not an error in
	a module procedure statment in a generic interface.
	* module.c (gfc_match_submodule): New function. Add handling
	for the 'module_procedure' attribute bit.
	(gfc_use_module): Make sure that a submodule cannot use itself.
	* parse.c (decode_statement): Set attr has_'import_set' for
	the interface declaration of module procedures. Handle a match
	occurring in 'gfc_match_submod_proc' and a match for
	'submodule'.
	(gfc_enclosing_unit): Include the state COMP_SUBMODULE.
	(gfc_ascii_statement): Add END SUBMODULE.
	(accept_statement): Add ST_SUBMODULE.
	(parse_spec): Disallow statement functions in a submodule
	specification part.
	(parse_contained): Add ST_END_SUBMODULE and COMP_SUBMODULE
	twice each.
	(get_modproc_result): Copy the result symbol of the interface.
	(parse_progunit): Call it.
	(set_syms_host_assoc): Make symbols from the ancestor module
	and submodules use associated, as required by the standard and
	set all private components public. Module procedures 'external'
	attribute bit is reset and the 'used_in_submodule' bit is set.
	(parse_module): If this is a submodule, use the ancestor module
	and submodules. Traverse the namespace, calling
	'set_syms_host_assoc'. Add ST_END_SUBMODULE and COMP_SUBMODULE.
	* parse.h : Add COMP_SUBMODULE.
	* primary.c (match_variable): Add COMP_SUBMODULE.
	* resolve.c (compare_fsyms): New function to compare the dummy
	characteristics of a module procedure with its interface.
	(resolve_fl_procedure): Compare the procedure, result and dummy
	characteristics of a module_procedure with its interface, using
	'compare_fsyms' for the dummy arguments.
	* symbol.c (gfc_add_procedure): Suppress the check for existing
	procedures in the case of a module procedure.
	(gfc_add_explicit_interface): Skip checks that must fail for
	module procedures.
	(gfc_add_type): Allow a new type to be added to module
	procedures, their results or their dummy arguments.
	(gfc_copy_dummy_sym): New function to generate new dummy args
	and copy the characteristics from the interface.
	* trans-decl.c (gfc_sym_mangled_function_id): Module procedures
	must always have their names mangled as if they are symbols
	coming from a declaration in a module.
	(gfc_get_symbol_decl): Add 'used_in_submodule' to the assert.
	(gfc_finish_var_decl): Symbols with the 'used_in_submodule' bit
	set are set DECL_EXTERNAL as if they were use associated.

2015-07-02  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/52846
	* gfortran.dg/submodule_1.f90: New test
	* gfortran.dg/submodule_2.f90: New test
	* gfortran.dg/submodule_3.f90: New test
	* gfortran.dg/submodule_4.f90: New test
	* gfortran.dg/submodule_5.f90: New test
	* gfortran.dg/submodule_6.f90: New test
	* gfortran.dg/submodule_7.f90: New test


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@225354 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 72 insertions, 3 deletions

diff --git a/gcc/fortran/module.c b/gcc/fortran/module.c
index 8bcc091a251..24662f464de 100644
--- a/gcc/fortran/module.c
+++ b/gcc/fortran/module.c
@@ -716,6 +716,67 @@ cleanup:
 }
 
 
+/* Match a SUBMODULE statement.  */
+
+match
+gfc_match_submodule (void)
+{
+  match m;
+  char name[GFC_MAX_SYMBOL_LEN + 1];
+  gfc_use_list *use_list;
+
+  if (!gfc_notify_std (GFC_STD_F2008, "SUBMODULE declaration at %C"))
+    return MATCH_ERROR;
+
+  gfc_new_block = NULL;
+  gcc_assert (module_list == NULL);
+
+  if (gfc_match_char ('(') != MATCH_YES)
+    goto syntax;
+
+  while (1)
+    {
+      m = gfc_match (" %n", name);
+      if (m != MATCH_YES)
+	goto syntax;
+
+      use_list = gfc_get_use_list ();
+      use_list->module_name = gfc_get_string (name);
+      use_list->where = gfc_current_locus;
+
+      if (module_list)
+	{
+	  gfc_use_list *last = module_list;
+	  while (last->next)
+	    last = last->next;
+	  last->next = use_list;
+	}
+      else
+	module_list = use_list;
+
+      if (gfc_match_char (')') == MATCH_YES)
+	break;
+
+      if (gfc_match_char (':') != MATCH_YES)
+	goto syntax;
+    }
+
+  m = gfc_match (" %s%t", &gfc_new_block);
+  if (m != MATCH_YES)
+    goto syntax;
+
+  if (!gfc_add_flavor (&gfc_new_block->attr, FL_MODULE,
+		       gfc_new_block->name, NULL))
+    return MATCH_ERROR;
+
+  return MATCH_YES;
+
+syntax:
+  gfc_error ("Syntax error in SUBMODULE statement at %C");
+  return MATCH_ERROR;
+}
+
+
 /* Given a name and a number, inst, return the inst name
    under which to load this symbol. Returns NULL if this
    symbol shouldn't be loaded. If inst is zero, returns
@@ -1887,7 +1948,7 @@ typedef enum
   AB_IS_CLASS, AB_PROCEDURE, AB_PROC_POINTER, AB_ASYNCHRONOUS, AB_CODIMENSION,
   AB_COARRAY_COMP, AB_VTYPE, AB_VTAB, AB_CONTIGUOUS, AB_CLASS_POINTER,
   AB_IMPLICIT_PURE, AB_ARTIFICIAL, AB_UNLIMITED_POLY, AB_OMP_DECLARE_TARGET,
-  AB_ARRAY_OUTER_DEPENDENCY
+  AB_ARRAY_OUTER_DEPENDENCY, AB_MODULE_PROCEDURE
 }
 ab_attribute;
 
@@ -1944,6 +2005,7 @@ static const mstring attr_bits[] =
     minit ("UNLIMITED_POLY", AB_UNLIMITED_POLY),
     minit ("OMP_DECLARE_TARGET", AB_OMP_DECLARE_TARGET),
     minit ("ARRAY_OUTER_DEPENDENCY", AB_ARRAY_OUTER_DEPENDENCY),
+    minit ("MODULE_PROCEDURE", AB_MODULE_PROCEDURE),
     minit (NULL, -1)
 };
 
@@ -2126,6 +2188,8 @@ mio_symbol_attribute (symbol_attribute *attr)
 	MIO_NAME (ab_attribute) (AB_OMP_DECLARE_TARGET, attr_bits);
       if (attr->array_outer_dependency)
 	MIO_NAME (ab_attribute) (AB_ARRAY_OUTER_DEPENDENCY, attr_bits);
+      if (attr->module_procedure)
+	MIO_NAME (ab_attribute) (AB_MODULE_PROCEDURE, attr_bits);
 
       mio_rparen ();
 
@@ -2295,6 +2359,9 @@ mio_symbol_attribute (symbol_attribute *attr)
 	    case AB_ARRAY_OUTER_DEPENDENCY:
 	      attr->array_outer_dependency =1;
 	      break;
+	    case AB_MODULE_PROCEDURE:
+	      attr->module_procedure =1;
+	      break;
 	    }
 	}
     }
@@ -6757,8 +6824,10 @@ gfc_use_module (gfc_use_list *module)
 
   /* Make sure we're not reading the same module that we may be building.  */
   for (p = gfc_state_stack; p; p = p->previous)
-    if (p->state == COMP_MODULE && strcmp (p->sym->name, module_name) == 0)
-      gfc_fatal_error ("Can't USE the same module we're building!");
+    if ((p->state == COMP_MODULE || p->state == COMP_SUBMODULE)
+	 && strcmp (p->sym->name, module_name) == 0)
+      gfc_fatal_error ("Can't USE the same %smodule we're building!",
+		       p->state == COMP_SUBMODULE ? "sub" : "");
 
   init_pi_tree ();
   init_true_name_tree ();