re PR fortran/69834 ([OOP] Collision in derived type hashes)

2016-10-23  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/69834
	* class.c (gfc_find_derived_vtab): Obtain the gsymbol for the
	derived type's module. If the gsymbol is present and the top
	level namespace corresponds to a module, use the gsymbol name
	space. In the search to see if the vtable exists, try the gsym
	namespace first.
	* dump-parse-tree (show_code_node): Modify select case dump to
	show select type construct.
	* resolve.c (build_loc_call): New function.
	(resolve_select_type): Add check for repeated type is cases.
	Retain selector expression and use it later instead of expr1.
	Exclude deferred length TYPE IS cases and emit error message.
	Store the address for the vtable in the 'low' expression and
	the hash value in the 'high' expression, for each case. Do not
	call resolve_select.
	* trans.c(trans_code) : Call gfc_trans_select_type.
	* trans-stmt.c (gfc_trans_select_type_cases): New function.
	(gfc_trans_select_type): New function.
	* trans-stmt.h : Add prototype for gfc_trans_select_type.

2016-10-23  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/69834
	* gfortran.dg/select_type_1.f03: Change error for overlapping
	TYPE IS cases.
	* gfortran.dg/select_type_36.f03: New test.

From-SVN: r241450

1 files changed, 80 insertions, 20 deletions

diff --git a/gcc/fortran/resolve.c b/gcc/fortran/resolve.c
index 6dae6fb..2a64ab7 100644
--- a/gcc/fortran/resolve.c
+++ b/gcc/fortran/resolve.c
@@ -8369,6 +8369,25 @@ fixup_array_ref (gfc_expr **expr1, gfc_expr *expr2,
 }
 
 
+static gfc_expr *
+build_loc_call (gfc_expr *sym_expr)
+{
+  gfc_expr *loc_call;
+  loc_call = gfc_get_expr ();
+  loc_call->expr_type = EXPR_FUNCTION;
+  gfc_get_sym_tree ("loc", gfc_current_ns, &loc_call->symtree, false);
+  loc_call->symtree->n.sym->attr.flavor = FL_PROCEDURE;
+  loc_call->symtree->n.sym->attr.intrinsic = 1;
+  loc_call->symtree->n.sym->result = loc_call->symtree->n.sym;
+  gfc_commit_symbol (loc_call->symtree->n.sym);
+  loc_call->ts.type = BT_INTEGER;
+  loc_call->ts.kind = gfc_index_integer_kind;
+  loc_call->value.function.isym = gfc_intrinsic_function_by_id (GFC_ISYM_LOC);
+  loc_call->value.function.actual = gfc_get_actual_arglist ();
+  loc_call->value.function.actual->expr = sym_expr;
+  return loc_call;
+}
+
 /* Resolve a SELECT TYPE statement.  */
 
 static void
@@ -8385,6 +8404,7 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
   int charlen = 0;
   int rank = 0;
   gfc_ref* ref = NULL;
+  gfc_expr *selector_expr = NULL;
 
   ns = code->ext.block.ns;
   gfc_resolve (ns);
@@ -8433,6 +8453,31 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
     {
       c = body->ext.block.case_list;
 
+      if (!error)
+	{
+	  /* Check for repeated cases.  */
+	  for (tail = code->block; tail; tail = tail->block)
+	    {
+	      gfc_case *d = tail->ext.block.case_list;
+	      if (tail == body)
+		break;
+
+	      if (c->ts.type == d->ts.type
+		  && ((c->ts.type == BT_DERIVED
+		       && c->ts.u.derived && d->ts.u.derived
+		       && !strcmp (c->ts.u.derived->name,
+				   d->ts.u.derived->name))
+		      || c->ts.type == BT_UNKNOWN
+		      || (!(c->ts.type == BT_DERIVED || c->ts.type == BT_CLASS)
+			  && c->ts.kind == d->ts.kind)))
+		{
+		  gfc_error ("TYPE IS at %L overlaps with TYPE IS at %L",
+			     &c->where, &d->where);
+		  return;
+		}
+	    }
+	}
+
       /* Check F03:C815.  */
       if ((c->ts.type == BT_DERIVED || c->ts.type == BT_CLASS)
 	  && !selector_type->attr.unlimited_polymorphic
@@ -8460,7 +8505,8 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
 	}
 
       /* Check F03:C814.  */
-      if (c->ts.type == BT_CHARACTER && c->ts.u.cl->length != NULL)
+      if (c->ts.type == BT_CHARACTER
+	  && (c->ts.u.cl->length != NULL || c->ts.deferred))
 	{
 	  gfc_error ("The type-spec at %L shall specify that each length "
 		     "type parameter is assumed", &c->where);
@@ -8549,31 +8595,47 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
   else
     ns->code->next = new_st;
   code = new_st;
-  code->op = EXEC_SELECT;
+  code->op = EXEC_SELECT_TYPE;
 
+  /* Use the intrinsic LOC function to generate an integer expression
+     for the vtable of the selector.  Note that the rank of the selector
+     expression has to be set to zero.  */
   gfc_add_vptr_component (code->expr1);
-  gfc_add_hash_component (code->expr1);
+  code->expr1->rank = 0;
+  code->expr1 = build_loc_call (code->expr1);
+  selector_expr = code->expr1->value.function.actual->expr;
 
   /* Loop over TYPE IS / CLASS IS cases.  */
   for (body = code->block; body; body = body->block)
     {
+      gfc_symbol *vtab;
+      gfc_expr *e;
       c = body->ext.block.case_list;
 
-      if (c->ts.type == BT_DERIVED)
-	c->low = c->high = gfc_get_int_expr (gfc_default_integer_kind, NULL,
-					     c->ts.u.derived->hash_value);
-      else if (c->ts.type != BT_CLASS && c->ts.type != BT_UNKNOWN)
+      /* Generate an index integer expression for address of the
+	 TYPE/CLASS vtable and store it in c->low.  The hash expression
+	 is stored in c->high and is used to resolve intrinsic cases.  */
+      if (c->ts.type != BT_UNKNOWN)
 	{
-	  gfc_symbol *ivtab;
-	  gfc_expr *e;
+	  if (c->ts.type == BT_DERIVED || c->ts.type == BT_CLASS)
+	    {
+	      vtab = gfc_find_derived_vtab (c->ts.u.derived);
+	      gcc_assert (vtab);
+	      c->high = gfc_get_int_expr (gfc_default_integer_kind, NULL,
+					  c->ts.u.derived->hash_value);
+	    }
+	  else
+	    {
+	      vtab = gfc_find_vtab (&c->ts);
+	      gcc_assert (vtab && CLASS_DATA (vtab)->initializer);
+	      e = CLASS_DATA (vtab)->initializer;
+	      c->high = gfc_copy_expr (e);
+	    }
 
-	  ivtab = gfc_find_vtab (&c->ts);
-	  gcc_assert (ivtab && CLASS_DATA (ivtab)->initializer);
-	  e = CLASS_DATA (ivtab)->initializer;
-	  c->low = c->high = gfc_copy_expr (e);
+	  e = gfc_lval_expr_from_sym (vtab);
+	  c->low = build_loc_call (e);
 	}
-
-      else if (c->ts.type == BT_UNKNOWN)
+      else
 	continue;
 
       /* Associate temporary to selector.  This should only be done
@@ -8599,8 +8661,8 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
 
       st = gfc_find_symtree (ns->sym_root, name);
       gcc_assert (st->n.sym->assoc);
-      st->n.sym->assoc->target = gfc_get_variable_expr (code->expr1->symtree);
-      st->n.sym->assoc->target->where = code->expr1->where;
+      st->n.sym->assoc->target = gfc_get_variable_expr (selector_expr->symtree);
+      st->n.sym->assoc->target->where = selector_expr->where;
       if (c->ts.type != BT_CLASS && c->ts.type != BT_UNKNOWN)
 	{
 	  gfc_add_data_component (st->n.sym->assoc->target);
@@ -8720,7 +8782,7 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
 	  new_st->expr1->value.function.isym->id = GFC_ISYM_EXTENDS_TYPE_OF;
 	  /* Set up arguments.  */
 	  new_st->expr1->value.function.actual = gfc_get_actual_arglist ();
-	  new_st->expr1->value.function.actual->expr = gfc_get_variable_expr (code->expr1->symtree);
+	  new_st->expr1->value.function.actual->expr = gfc_get_variable_expr (selector_expr->symtree);
 	  new_st->expr1->value.function.actual->expr->where = code->loc;
 	  gfc_add_vptr_component (new_st->expr1->value.function.actual->expr);
 	  vtab = gfc_find_derived_vtab (body->ext.block.case_list->ts.u.derived);
@@ -8748,8 +8810,6 @@ resolve_select_type (gfc_code *code, gfc_namespace *old_ns)
 
   if (ref)
     free (ref);
-
-  resolve_select (code, true);
 }