utils.c (pad_type_hash): Use hashval_t for hash value.

	* gcc-interface/utils.c (pad_type_hash): Use hashval_t for hash value.
	(convert): Do not use an unchecked conversion for converting from a
	type to another type padding it.

From-SVN: r253971

gcc/ada/ChangeLog

+2017-10-21  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc-interface/utils.c (pad_type_hash): Use hashval_t for hash value.
+	(convert): Do not use an unchecked conversion for converting from a
+	type to another type padding it.
+
 2017-10-20  Doug Rupp  <rupp@adacore.com>
 
 	* libgnarl/s-osinte__linux.ads (Relative_Timed_Wait): Add variable

gcc/ada/gcc-interface/utils.c

@@ -101,7 +101,7 @@ static tree handle_vector_type_attribute (tree *, tree, tree, int, bool *);
 
 /* Fake handler for attributes we don't properly support, typically because
    they'd require dragging a lot of the common-c front-end circuitry.  */
-static tree fake_attribute_handler      (tree *, tree, tree, int, bool *);
+static tree fake_attribute_handler (tree *, tree, tree, int, bool *);
 
 /* Table of machine-independent internal attributes for Ada.  We support
    this minimal set of attributes to accommodate the needs of builtins.  */
@@ -222,8 +222,9 @@ static GTY((deletable)) tree free_block_chain;
 /* A hash table of padded types.  It is modelled on the generic type
    hash table in tree.c, which must thus be used as a reference.  */
 
-struct GTY((for_user)) pad_type_hash {
-  unsigned long hash;
+struct GTY((for_user)) pad_type_hash
+{
+  hashval_t hash;
   tree type;
 };
 
@@ -4249,10 +4250,13 @@ convert (tree type, tree expr)
 	return convert (type, TREE_OPERAND (expr, 0));
 
       /* If the inner type is of self-referential size and the expression type
-	 is a record, do this as an unchecked conversion.  But first pad the
-	 expression if possible to have the same size on both sides.  */
+	 is a record, do this as an unchecked conversion unless both types are
+	 essentially the same.  But first pad the expression if possible to
+	 have the same size on both sides.  */
       if (ecode == RECORD_TYPE
-	  && CONTAINS_PLACEHOLDER_P (DECL_SIZE (TYPE_FIELDS (type))))
+	  && CONTAINS_PLACEHOLDER_P (DECL_SIZE (TYPE_FIELDS (type)))
+	  && TYPE_MAIN_VARIANT (etype)
+	     != TYPE_MAIN_VARIANT (TREE_TYPE (TYPE_FIELDS (type))))
 	{
 	  if (TREE_CODE (TYPE_SIZE (etype)) == INTEGER_CST)
 	    expr = convert (maybe_pad_type (etype, TYPE_SIZE (type), 0, Empty,

gcc/testsuite/ChangeLog

+2017-10-21  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/specs/discr_private.ads: Rename into ...
+	* gnat.dg/specs/discr2.ads: ...this.
+	* gnat.dg/specs/discr_record_constant.ads: Rename into...
+	* gnat.dg/specs/discr3.ads: ...this.
+	* gnat.dg/specs/discr4.ads: New test.
+	* gnat.dg/specs/discr4_pkg.ads: New helper.
+
 2017-10-21  Paul Thomas  <pault@gcc.gnu.org>
 
 	PR fortran/82586

gcc/testsuite/gnat.dg/specs/discr_private.ads → gcc/testsuite/gnat.dg/specs/discr2.ads

 -- { dg-do compile }
 -- { dg-options "-gnatws" }
 
-package Discr_Private is
+package Discr2 is
 
    package Dec is
       type T_DECIMAL (Prec : Integer := 1) is private;
@@ -47,4 +47,4 @@ package Discr_Private is
        end case;
    end record;
 
-end Discr_Private;
+end Discr2;

gcc/testsuite/gnat.dg/specs/discr_record_constant.ads → gcc/testsuite/gnat.dg/specs/discr3.ads

@@ -2,7 +2,7 @@
 
 pragma Restrictions (No_Implicit_Heap_Allocations);
 
-package Discr_Record_Constant is
+package Discr3 is
 
    type T (Big : Boolean := False) is record
       case Big is
@@ -19,4 +19,4 @@ package Discr_Record_Constant is
     Con : constant T := D;    --  Violation of restriction
     Ter : constant T := Con;  --  Violation of restriction
 
-end Discr_Record_Constant;
+end Discr3;

gcc/testsuite/gnat.dg/specs/discr4.ads

+-- { dg-do compile }
+-- { dg-options "-O" }
+
+with Disc4_Pkg; use Disc4_Pkg;
+
+package Disc4 is
+
+   type Data is record
+      Val : Rec;
+      Set : Boolean;
+   end record;
+
+   type Pair is record
+      Lower, Upper : Data;
+   end record;
+
+   function Build (L, U : Rec) return Pair is ((L, True), (U, False));
+
+   C1 : constant Pair := Build (Rec_One, Rec_Three);
+
+   C2 : constant Pair := Build (Get (0), Rec_Three);
+
+end Disc4;

gcc/testsuite/gnat.dg/specs/discr4_pkg.ads

+package Disc4_Pkg is
+
+   type Enum is (One, Two, Three);
+
+   type Rec is private;
+
+   Rec_One : constant Rec;
+   Rec_Three  : constant Rec;
+
+   function Get (Value : Integer) return Rec;
+
+private
+
+   type Rec (D : Enum := Two) is record
+      case D is
+         when One => null;
+         when Two => Value : Integer;
+         when Three => null;
+      end case;
+   end record;
+
+   Rec_One   : constant Rec := (D => One);
+   Rec_Three : constant Rec := (D => Three);
+
+   function Get (Value : Integer) return Rec is (Two, Value);
+
+end Disc4_Pkg;