re PR fortran/38936 ([F03] ASSOCIATE construct / improved SELECT TYPE (a=>expr))

2010-06-10  Daniel Kraft  <d@domob.eu>

	PR fortran/38936
	* gfortran.h (enum gfc_statement): Add ST_ASSOCIATE, ST_END_ASSOCIATE.
	(struct gfc_symbol): New field `assoc'.
	(struct gfc_association_list): New struct.
	(struct gfc_code): New struct `block' in union, move `ns' there
	and add association list.
	(gfc_free_association_list): New method.
	(gfc_has_vector_subscript): Made public;
	* match.h (gfc_match_associate): New method.
	* parse.h (enum gfc_compile_state): Add COMP_ASSOCIATE.
	* decl.c (gfc_match_end): Handle ST_END_ASSOCIATE.
	* interface.c (gfc_has_vector_subscript): Made public.
	(compare_actual_formal): Rename `has_vector_subscript' accordingly.
	* match.c (gfc_match_associate): New method.
	(gfc_match_select_type): Change reference to gfc_code's `ns' field.
	* primary.c (match_variable): Don't allow names associated to expr here.
	* parse.c (decode_statement): Try matching ASSOCIATE statement.
	(case_exec_markers, case_end): Add ASSOCIATE statement.
	(gfc_ascii_statement): Hande ST_ASSOCIATE and ST_END_ASSOCIATE.
	(parse_associate): New method.
	(parse_executable): Handle ST_ASSOCIATE.
	(parse_block_construct): Change reference to gfc_code's `ns' field.
	* resolve.c (resolve_select_type): Ditto.
	(resolve_code): Ditto.
	(resolve_block_construct): Ditto and add comment.
	(resolve_select_type): Set association list in generated BLOCK to NULL.
	(resolve_symbol): Resolve associate names.
	* st.c (gfc_free_statement): Change reference to gfc_code's `ns' field
	and free association list.
	(gfc_free_association_list): New method.
	* symbol.c (gfc_new_symbol): NULL new field `assoc'.
	* trans-stmt.c (gfc_trans_block_construct): Change reference to
	gfc_code's `ns' field.

2010-06-10  Daniel Kraft  <d@domob.eu>

	PR fortran/38936
	* gfortran.dg/associate_1.f03: New test.
	* gfortran.dg/associate_2.f95: New test.
	* gfortran.dg/associate_3.f03: New test.
	* gfortran.dg/associate_4.f08: New test.

From-SVN: r160550

1 files changed, 93 insertions, 1 deletions

diff --git a/gcc/fortran/match.c b/gcc/fortran/match.c
index 2cbac02..8c43531 100644
--- a/gcc/fortran/match.c
+++ b/gcc/fortran/match.c
@@ -1797,6 +1797,98 @@ gfc_match_block (void)
 }
 
 
+/* Match an ASSOCIATE statement.  */
+
+match
+gfc_match_associate (void)
+{
+  if (gfc_match_label () == MATCH_ERROR)
+    return MATCH_ERROR;
+
+  if (gfc_match (" associate") != MATCH_YES)
+    return MATCH_NO;
+
+  /* Match the association list.  */
+  if (gfc_match_char ('(') != MATCH_YES)
+    {
+      gfc_error ("Expected association list at %C");
+      return MATCH_ERROR;
+    }
+  new_st.ext.block.assoc = NULL;
+  while (true)
+    {
+      gfc_association_list* newAssoc = gfc_get_association_list ();
+      gfc_association_list* a;
+
+      /* Match the next association.  */
+      if (gfc_match (" %n => %e", newAssoc->name, &newAssoc->target)
+	    != MATCH_YES)
+	{
+	  gfc_error ("Expected association at %C");
+	  goto assocListError;
+	}
+
+      /* Check that the current name is not yet in the list.  */
+      for (a = new_st.ext.block.assoc; a; a = a->next)
+	if (!strcmp (a->name, newAssoc->name))
+	  {
+	    gfc_error ("Duplicate name '%s' in association at %C",
+		       newAssoc->name);
+	    goto assocListError;
+	  }
+
+      /* The target expression must not be coindexed.  */
+      if (gfc_is_coindexed (newAssoc->target))
+	{
+	  gfc_error ("Association target at %C must not be coindexed");
+	  goto assocListError;
+	}
+
+      /* The target is a variable (and may be used as lvalue) if it's an
+	 EXPR_VARIABLE and does not have vector-subscripts.  */
+      newAssoc->variable = (newAssoc->target->expr_type == EXPR_VARIABLE
+			    && !gfc_has_vector_subscript (newAssoc->target));
+
+      /* Put it into the list.  */
+      newAssoc->next = new_st.ext.block.assoc;
+      new_st.ext.block.assoc = newAssoc;
+
+      /* Try next one or end if closing parenthesis is found.  */
+      gfc_gobble_whitespace ();
+      if (gfc_peek_char () == ')')
+	break;
+      if (gfc_match_char (',') != MATCH_YES)
+	{
+	  gfc_error ("Expected ')' or ',' at %C");
+	  return MATCH_ERROR;
+	}
+
+      continue;
+
+assocListError:
+      gfc_free (newAssoc);
+      goto error;
+    }
+  if (gfc_match_char (')') != MATCH_YES)
+    {
+      /* This should never happen as we peek above.  */
+      gcc_unreachable ();
+    }
+
+  if (gfc_match_eos () != MATCH_YES)
+    {
+      gfc_error ("Junk after ASSOCIATE statement at %C");
+      goto error;
+    }
+
+  return MATCH_YES;
+
+error:
+  gfc_free_association_list (new_st.ext.block.assoc);
+  return MATCH_ERROR;
+}
+
+
 /* Match a DO statement.  */
 
 match
@@ -4361,7 +4453,7 @@ gfc_match_select_type (void)
   new_st.op = EXEC_SELECT_TYPE;
   new_st.expr1 = expr1;
   new_st.expr2 = expr2;
-  new_st.ext.ns = gfc_current_ns;
+  new_st.ext.block.ns = gfc_current_ns;
 
   select_type_push (expr1->symtree->n.sym);