re PR fortran/45197 ([F2008] Allow IMPURE elemental procedures)

2010-08-15  Daniel Kraft  <d@domob.eu>

	PR fortran/45197
	* decl.c (gfc_match_prefix): Match IMPURE prefix and mark ELEMENTAL
	routines not IMPURE also as PURE.
	* intrinsic.c (enum klass): New class `CLASS_PURE' and renamed
	`NO_CLASS' in `CLASS_IMPURE'.
	(add_sym): Set symbol-attributes `pure' and `elemental' correctly.
	(add_sym_0s): Renamed `NO_CLASS' in `CLASS_IMPURE'.
	(add_functions): Ditto.
	(add_subroutines): Ditto and mark `MOVE_ALLOC' as CLASS_PURE.
	* resolve.c (gfc_pure): Do not treat ELEMENTAL as automatically PURE.
	(resolve_formal_arglist): Check that arguments to ELEMENTAL procedures
	are not ALLOCATABLE and have their INTENT specified.

2010-08-15  Daniel Kraft  <d@domob.eu>

	PR fortran/45197
	* gfortran.dg/elemental_args_check_3.f90: New test.
	* gfortran.dg/impure_1.f08: New test.
	* gfortran.dg/impure_2.f08: New test.
	* gfortran.dg/impure_3.f90: New test.
	* gfortran.dg/typebound_proc_6.f03: Changed expected error message.

From-SVN: r163261

1 files changed, 58 insertions, 22 deletions

diff --git a/gcc/fortran/decl.c b/gcc/fortran/decl.c
index 91eb710..be41af8 100644
--- a/gcc/fortran/decl.c
+++ b/gcc/fortran/decl.c
@@ -4052,45 +4052,81 @@ match
 gfc_match_prefix (gfc_typespec *ts)
 {
   bool seen_type;
+  bool seen_impure;
+  bool found_prefix;
 
   gfc_clear_attr (&current_attr);
-  seen_type = 0;
+  seen_type = false;
+  seen_impure = false;
 
   gcc_assert (!gfc_matching_prefix);
   gfc_matching_prefix = true;
 
-loop:
-  if (!seen_type && ts != NULL
-      && gfc_match_decl_type_spec (ts, 0) == MATCH_YES
-      && gfc_match_space () == MATCH_YES)
+  do
     {
+      found_prefix = false;
 
-      seen_type = 1;
-      goto loop;
-    }
+      if (!seen_type && ts != NULL
+	  && gfc_match_decl_type_spec (ts, 0) == MATCH_YES
+	  && gfc_match_space () == MATCH_YES)
+	{
 
-  if (gfc_match ("elemental% ") == MATCH_YES)
-    {
-      if (gfc_add_elemental (&current_attr, NULL) == FAILURE)
-	goto error;
+	  seen_type = true;
+	  found_prefix = true;
+	}
+
+      if (gfc_match ("elemental% ") == MATCH_YES)
+	{
+	  if (gfc_add_elemental (&current_attr, NULL) == FAILURE)
+	    goto error;
 
-      goto loop;
+	  found_prefix = true;
+	}
+
+      if (gfc_match ("pure% ") == MATCH_YES)
+	{
+	  if (gfc_add_pure (&current_attr, NULL) == FAILURE)
+	    goto error;
+
+	  found_prefix = true;
+	}
+
+      if (gfc_match ("recursive% ") == MATCH_YES)
+	{
+	  if (gfc_add_recursive (&current_attr, NULL) == FAILURE)
+	    goto error;
+
+	  found_prefix = true;
+	}
+
+      /* IMPURE is a somewhat special case, as it needs not set an actual
+	 attribute but rather only prevents ELEMENTAL routines from being
+	 automatically PURE.  */
+      if (gfc_match ("impure% ") == MATCH_YES)
+	{
+	  if (gfc_notify_std (GFC_STD_F2008,
+			      "Fortran 2008: IMPURE procedure at %C")
+		== FAILURE)
+	    goto error;
+
+	  seen_impure = true;
+	  found_prefix = true;
+	}
     }
+  while (found_prefix);
 
-  if (gfc_match ("pure% ") == MATCH_YES)
+  /* IMPURE and PURE must not both appear, of course.  */
+  if (seen_impure && current_attr.pure)
     {
-      if (gfc_add_pure (&current_attr, NULL) == FAILURE)
-	goto error;
-
-      goto loop;
+      gfc_error ("PURE and IMPURE must not appear both at %C");
+      goto error;
     }
 
-  if (gfc_match ("recursive% ") == MATCH_YES)
+  /* If IMPURE it not seen but the procedure is ELEMENTAL, mark it as PURE.  */
+  if (!seen_impure && current_attr.elemental && !current_attr.pure)
     {
-      if (gfc_add_recursive (&current_attr, NULL) == FAILURE)
+      if (gfc_add_pure (&current_attr, NULL) == FAILURE)
 	goto error;
-
-      goto loop;
     }
 
   /* At this point, the next item is not a prefix.  */