sem_ch6.adb (Set_Formal_Mode): If the subtype has a non_null indicator, indicate that the formal can never be null.

2005-03-29  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch6.adb (Set_Formal_Mode): If the subtype has a non_null
	indicator, indicate that the formal can never be null.
	(Process_Formals): If a formal has a non_null indicator, insert the
	resulting subtype immediately before the enclosing subprogram decl,
	and not at the beginning of the corresponding declarative part, to
	prevent access before elaboration (Ada2005).

From-SVN: r97185
This commit is contained in:
Ed Schonberg 2005-03-29 18:21:32 +02:00 committed by Arnaud Charlet
parent 981234802e
commit 2813bb6b35

View File

@ -5089,8 +5089,8 @@ package body Sem_Ch6 is
-- Ada 2005 (AI-231): Create and decorate an internal subtype
-- declaration corresponding to the null-excluding type of the
-- formal in the enclosing scope. In addition, replace the
-- parameter type of the formal to this internal subtype.
-- formal in the enclosing scope. Finally, replace the
-- parameter type of the formal with the internal subtype.
if Null_Exclusion_Present (Param_Spec) then
declare
@ -5105,7 +5105,7 @@ package body Sem_Ch6 is
Ptype : constant Node_Id := Parameter_Type (Param_Spec);
Decl : Node_Id;
P : Node_Id := Parent (Parent (Related_Nod));
P : Node_Id := Parent (Related_Nod);
begin
Set_Is_Internal (Anon);
@ -5127,12 +5127,13 @@ package body Sem_Ch6 is
Mark_Rewrite_Insertion (Decl);
-- Insert the new declaration in the nearest enclosing scope
-- in front of the subprogram or entry declaration.
while not Has_Declarations (P) loop
while not Is_List_Member (P) loop
P := Parent (P);
end loop;
Prepend (Decl, Declarations (P));
Insert_Before (P, Decl);
Rewrite (Ptype, New_Occurrence_Of (Anon, Loc));
Mark_Rewrite_Insertion (Ptype);
@ -5456,15 +5457,24 @@ package body Sem_Ch6 is
if Nkind (Parameter_Type (Spec)) = N_Access_Definition then
-- Ada 2005 (AI-231): This behaviour has been modified in Ada 2005.
-- It is only forced if the null_exclusion appears.
-- Ada 2005 (AI-231): In Ada95, access parameters are always non-
-- null; In Ada 2005, only if then null_exclusion is explicit.
if Ada_Version < Ada_05
or else Null_Exclusion_Present (Spec)
or else Can_Never_Be_Null (Etype (Formal_Id))
then
Set_Is_Known_Non_Null (Formal_Id);
Set_Can_Never_Be_Null (Formal_Id);
end if;
elsif Is_Access_Type (Etype (Formal_Id))
and then Can_Never_Be_Null (Etype (Formal_Id))
then
-- Ada 2005: The access subtype may be declared with null-exclusion
Set_Is_Known_Non_Null (Formal_Id);
Set_Can_Never_Be_Null (Formal_Id);
end if;
Set_Mechanism (Formal_Id, Default_Mechanism);