ada: Restore fix for controlled dynamic allocation with BIP function call

The resolution made some time ago had been that a dynamic allocation for
a limited type that needs finalization with a function call as expression
always needs to be done in the called function, even if the limited type
has a known size.  But the fix implementing this resolution was dropped
inadvertently at some point.

The change also contains a small tweak for Expand_N_Object_Declaration
and a small related cleanup in the finalization machinery.

gcc/ada/

	* exp_ch3.adb (Expand_N_Object_Declaration): In the case of a
	return object of a BIP function that needs finalization, save
	the assignment statement made to initialize it, if any.
	* exp_ch6.ads (BIP_Formal_Kind): Adjust description.
	* exp_ch6.adb (Make_Build_In_Place_Call_In_Allocator): Make a
	couple of adjustments to the commentary.
	(Needs_BIP_Alloc_Form): Also return true if the function needs
	a BIP_Finalization_Master parameter.
	* exp_ch7.adb (Build_BIP_Cleanup_Stmts): Remove now always true
	test on Needs_BIP_Alloc_Form.
	(Attach_Object_To_Master_Node): Remove duplication in comment.

1 files changed, 12 insertions, 10 deletions

diff --git a/gcc/ada/exp_ch6.ads b/gcc/ada/exp_ch6.ads
index 12a9ce3..79e4120 100644
--- a/gcc/ada/exp_ch6.ads
+++ b/gcc/ada/exp_ch6.ads
@@ -47,8 +47,8 @@ package Exp_Ch6 is
    --  nodes (e.g. the filling of the corresponding Dispatch Table for
    --  Primitive Operations)
 
-   --  The following type defines the various forms of allocation used for the
-   --  results of build-in-place function calls.
+   --  Ada 2005 (AI-318-02): The following type defines the various forms of
+   --  allocation used for the result of build-in-place function calls.
 
    type BIP_Allocation_Form is
      (Unspecified,
@@ -57,22 +57,24 @@ package Exp_Ch6 is
       Global_Heap,
       User_Storage_Pool);
 
-   type BIP_Formal_Kind is
    --  Ada 2005 (AI-318-02): This type defines the kinds of implicit extra
    --  formals created for build-in-place functions. The order of these
    --  enumeration literals matches the order in which the formals are
    --  declared. See Sem_Ch6.Create_Extra_Formals.
 
+   type BIP_Formal_Kind is
      (BIP_Alloc_Form,
-      --  Present if result subtype is unconstrained or tagged. Indicates
-      --  whether the return object is allocated by the caller or callee, and
-      --  if the callee, whether to use the secondary stack or the heap. See
-      --  Create_Extra_Formals.
+      --  Present if result subtype is returned on the secondary stack or is
+      --  tagged: in this case, this indicates whether the return object is
+      --  allocated by the caller or callee, and if the callee, whether to
+      --  use the secondary stack, the global heap or a storage pool. Also
+      --  present if result type needs finalization.
 
       BIP_Storage_Pool,
-      --  Present if result subtype is unconstrained or tagged. If
-      --  BIP_Alloc_Form = User_Storage_Pool, this is a pointer to the pool
-      --  (of type access to Root_Storage_Pool'Class). Otherwise null.
+      --  Present if result subtype is returned on the secondary stack or is
+      --  tagged: in this case, if BIP_Alloc_Form = User_Storage_Pool, this
+      --  is a pointer to the pool (of type Root_Storage_Pool_Ptr); otherwise
+      --  this is null. Also present if result type needs finalization.
 
       BIP_Finalization_Master,
       --  Present if result type needs finalization. Pointer to caller's