2014-02-24 Sergey Rybin <rybin@adacore.com frybin>

	* gnat_ugn.texi: Misc updates.

2014-02-24  Hristian Kirtchev  <kirtchev@adacore.com>

	* exp_prag.adb (Expand_Old): Set the type of the generated temporary.

2014-02-24  Gary Dismukes  <dismukes@adacore.com>

	* layout.adb (Layout_Variant_Record): Instantiate
	Generic_Check_Choices and call Check_Choices before calling
	Build_Discr_Checking_Funcs, since we need Others_Discrete_Choices
	set to prevent generating incorrect discriminant-checking
	functions for 'others' variants (functions that unconditionally
	return True rather than accounting for the values covered by the
	'others' choice).
	* sem_eval.ads (Subtypes_Statically_Compatible): Add formal
	Formal_Derived_Matching.
	(Subtypes_Statically_Match): Add formal Formal_Derived_Matching.
	* sem_eval.adb (Subtypes_Statically_Compatible): Pass new
	Formal_Derived_Matching formal to Subtypes_Statically_Match.
	(Subtypes_Statically_Match): Suppress the Object_Size matching
	test in the case where Formal_Derived_Matching is True.
	* sem_ch12.adb (Validate_Derived_Type_Instance): Pass
	True for Formal_Derived_Matching_Formal on the call to
	Subtypes_Statically_Compatible.

From-SVN: r208068

1 files changed, 46 insertions, 0 deletions

diff --git a/gcc/ada/layout.adb b/gcc/ada/layout.adb
index ada36de..829d75c 100644
--- a/gcc/ada/layout.adb
+++ b/gcc/ada/layout.adb
@@ -37,6 +37,7 @@ with Opt;      use Opt;
 with Repinfo;  use Repinfo;
 with Sem;      use Sem;
 with Sem_Aux;  use Sem_Aux;
+with Sem_Case; use Sem_Case;
 with Sem_Ch13; use Sem_Ch13;
 with Sem_Eval; use Sem_Eval;
 with Sem_Util; use Sem_Util;
@@ -2224,9 +2225,54 @@ package body Layout is
             end if;
          end Layout_Component_List;
 
+         Others_Present : Boolean;
+         pragma Warnings (Off, Others_Present);
+         --  Indicates others present, not used in this case
+
+         procedure Non_Static_Choice_Error (Choice : Node_Id);
+         --  Error routine invoked by the generic instantiation below when
+         --  the variant part has a nonstatic choice.
+
+         package Variant_Choices_Processing is new
+           Generic_Check_Choices
+             (Process_Empty_Choice      => No_OP,
+              Process_Non_Static_Choice => Non_Static_Choice_Error,
+              Process_Associated_Node   => No_OP);
+         use Variant_Choices_Processing;
+
+         -----------------------------
+         -- Non_Static_Choice_Error --
+         -----------------------------
+
+         procedure Non_Static_Choice_Error (Choice : Node_Id) is
+         begin
+            Flag_Non_Static_Expr
+              ("choice given in case expression is not static!", Choice);
+         end Non_Static_Choice_Error;
+
       --  Start of processing for Layout_Variant_Record
 
       begin
+         --  Call Check_Choices here to ensure that Others_Discrete_Choices
+         --  gets set on any 'others' choice before the discriminant-checking
+         --  functions are generated. Otherwise the function for the 'others'
+         --  alternative will unconditionally return True, causing discriminant
+         --  checks to fail. However, Check_Choices is now normally delayed
+         --  until the type's freeze entity is processed, due to requirements
+         --  coming from subtype predicates, so doing it at this point is
+         --  probably not right in general, but it's not clear how else to deal
+         --  with this situation. Perhaps we should only generate declarations
+         --  for the checking functions here, and somehow delay generation of
+         --  their bodies, but that would be a nontrivial change. ???
+
+         declare
+            VP : constant Node_Id :=
+                   Variant_Part (Component_List (Type_Definition (Decl)));
+         begin
+            Check_Choices
+              (VP, Variants (VP), Etype (Name (VP)), Others_Present);
+         end;
+
          --  We need the discriminant checking functions, since we generate
          --  calls to these functions for the RM_Size expression, so make
          --  sure that these functions have been constructed in time.