[COMMITTED] ada: Fix loop unnesting issue.

["Marc Poulhiès" <poulhies@adacore.com>]

During loop unnesting, when the loop statements are wrapped in a code
block, the newly created block's scope must be set to the loop
scope (instead of the previous 'Current_Scope' that would point to an
upper scope).

gcc/ada/

	* sem_util.ads (Add_Block_Identifier): Add new extra Scope
	argument.
	* sem_util.adb (Add_Block_Identifier): Likewise and use this scope
	variable instead of Current_Scope.
	* exp_util.adb (Wrap_Statements_In_Block): Add new scope argument
	to Add_Block_Identifier call.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/exp_util.adb |  2 +-
 gcc/ada/sem_util.adb |  8 ++++++--
 gcc/ada/sem_util.ads | 14 +++++++++-----
 3 files changed, 16 insertions(+), 8 deletions(-)

diff --git a/gcc/ada/exp_util.adb b/gcc/ada/exp_util.adb
index 6c87debe456..35667028df1 100644
--- a/gcc/ada/exp_util.adb
+++ b/gcc/ada/exp_util.adb
@@ -11367,7 +11367,7 @@ package body Exp_Util is
          --  Create a label for the block in case the block needs to manage the
          --  secondary stack. A label allows for flag Uses_Sec_Stack to be set.
 
-         Add_Block_Identifier (Block_Nod, Block_Id);
+         Add_Block_Identifier (Block_Nod, Block_Id, Scop);
 
          --  When wrapping the statements of an iterator loop, check whether
          --  the loop requires secondary stack management and if so, propagate
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
index 28396a4c34b..9a7640b3147 100644
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -1044,7 +1044,11 @@ package body Sem_Util is
    -- Add_Block_Identifier --
    --------------------------
 
-   procedure Add_Block_Identifier (N : Node_Id; Id : out Entity_Id) is
+   procedure Add_Block_Identifier
+       (N : Node_Id;
+        Id : out Entity_Id;
+        Scope : Entity_Id := Current_Scope)
+   is
       Loc : constant Source_Ptr := Sloc (N);
    begin
       pragma Assert (Nkind (N) = N_Block_Statement);
@@ -1057,7 +1061,7 @@ package body Sem_Util is
       --  Create a new block label and set its attributes
 
       else
-         Id := New_Internal_Entity (E_Block, Current_Scope, Loc, 'B');
+         Id := New_Internal_Entity (E_Block, Scope, Loc, 'B');
          Set_Etype  (Id, Standard_Void_Type);
          Set_Parent (Id, N);
 
diff --git a/gcc/ada/sem_util.ads b/gcc/ada/sem_util.ads
index c23d358e2fb..88bfbfc2086 100644
--- a/gcc/ada/sem_util.ads
+++ b/gcc/ada/sem_util.ads
@@ -88,11 +88,6 @@ package Sem_Util is
    --  Add A to the list of access types to process when expanding the
    --  freeze node of E.
 
-   procedure Add_Block_Identifier (N : Node_Id; Id : out Entity_Id);
-   --  Given a block statement N, generate an internal E_Block label and make
-   --  it the identifier of the block. Id denotes the generated entity. If the
-   --  block already has an identifier, Id returns the entity of its label.
-
    procedure Add_Global_Declaration (N : Node_Id);
    --  These procedures adds a declaration N at the library level, to be
    --  elaborated before any other code in the unit. It is used for example
@@ -678,6 +673,15 @@ package Sem_Util is
    function Current_Scope return Entity_Id;
    --  Get entity representing current scope
 
+   procedure Add_Block_Identifier
+       (N : Node_Id;
+        Id : out Entity_Id;
+        Scope : Entity_Id := Current_Scope);
+   --  Given a block statement N, generate an internal E_Block label and make
+   --  it the identifier of the block. Scope denotes the scope in which the
+   --  generated entity Id is created and defaults to the current scope. If the
+   --  block already has an identifier, Id returns the entity of its label.
+
    function Current_Scope_No_Loops return Entity_Id;
    --  Return the current scope ignoring internally generated loops
 
-- 
2.34.1