This patch fixes an issue in the compiler whereby it fails to recognize
the presence of a current instance of an incomplete type when the
instance is used within a default expression for a record component.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* exp_ch3.adb (Build_Assignment): Replace current instance of
type with Init_Proc formal.
* sem_attr.adb (OK_Self_Reference): Handle recognition of
Current_Instance to detect certain expansion.
* sem_ch4.adb (Analyze_One_Call): Set actual's type when the
actual in question is a current instance and its corresponding
formal is an incomplete type.
* sem_util.adb (Is_Current_Instance): Add check for incomplete
views and add comment.diff --git a/gcc/ada/exp_ch3.adb b/gcc/ada/exp_ch3.adb
--- a/gcc/ada/exp_ch3.adb
+++ b/gcc/ada/exp_ch3.adb
@@ -2022,6 +2022,25 @@ package body Exp_Ch3 is
Elmt2 => Defining_Identifier (First
(Parameter_Specifications
(Parent (Proc_Id)))));
+
+ -- If the type has an incomplete view, a current instance
+ -- may have an incomplete type. In that case, it must also be
+ -- replaced by the formal of the Init_Proc.
+
+ if Nkind (Parent (Rec_Type)) = N_Full_Type_Declaration
+ and then Present (Incomplete_View (Parent (Rec_Type)))
+ then
+ Append_Elmt (
+ N => Defining_Identifier
+ (Incomplete_View (Parent (Rec_Type))),
+ To => Map);
+ Append_Elmt (
+ N => Defining_Identifier
+ (First
+ (Parameter_Specifications
+ (Parent (Proc_Id)))),
+ To => Map);
+ end if;
end if;
Exp := New_Copy_Tree (Exp, New_Scope => Proc_Id, Map => Map);
diff --git a/gcc/ada/sem_attr.adb b/gcc/ada/sem_attr.adb
--- a/gcc/ada/sem_attr.adb
+++ b/gcc/ada/sem_attr.adb
@@ -989,7 +989,15 @@ package body Sem_Attr is
Set_Etype (P, Typ);
end if;
- if Typ = Scop then
+ -- A current instance typically appears immediately within
+ -- the type declaration, but may be nested within an internally
+ -- generated temporary scope - as for an aggregate of a
+ -- discriminated component.
+
+ if Typ = Scop
+ or else (In_Open_Scopes (Typ)
+ and then not Comes_From_Source (Scop))
+ then
declare
Q : Node_Id := Parent (N);
diff --git a/gcc/ada/sem_ch4.adb b/gcc/ada/sem_ch4.adb
--- a/gcc/ada/sem_ch4.adb
+++ b/gcc/ada/sem_ch4.adb
@@ -3727,6 +3727,24 @@ package body Sem_Ch4 is
Next_Actual (Actual);
Next_Formal (Formal);
+ -- A current instance used as an actual of a function,
+ -- whose body has not been seen, may include a formal
+ -- whose type is an incomplete view of an enclosing
+ -- type declaration containing the current call (e.g.
+ -- in the Expression for a component declaration).
+
+ -- In this case, update the signature of the subprogram
+ -- so the formal has the type of the full view.
+
+ elsif Inside_Init_Proc
+ and then Nkind (Actual) = N_Identifier
+ and then Ekind (Etype (Formal)) = E_Incomplete_Type
+ and then Etype (Actual) = Full_View (Etype (Formal))
+ then
+ Set_Etype (Formal, Etype (Actual));
+ Next_Actual (Actual);
+ Next_Formal (Formal);
+
-- Handle failed type check
else
diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb
--- a/gcc/ada/sem_util.adb
+++ b/gcc/ada/sem_util.adb
@@ -16680,7 +16680,18 @@ package body Sem_Util is
| N_Private_Type_Declaration
| N_Subtype_Declaration
and then Comes_From_Source (P)
- and then Defining_Entity (P) = Typ
+
+ -- If the type has a previous incomplete declaration, the
+ -- reference in the type definition may have the incomplete
+ -- view. So, here we detect if this incomplete view is a current
+ -- instance by checking if its full view is the entity of the
+ -- full declaration begin analyzed.
+
+ and then
+ (Defining_Entity (P) = Typ
+ or else
+ (Ekind (Typ) = E_Incomplete_Type
+ and then Full_View (Typ) = Defining_Entity (P)))
then
return True;
