This removes obsolete code that would prevent a subtype dependent on a
private type from having its views switched when those of the private
type are switched by Switch_View.
Not switching the views in this case is problematic because this is not
in keeping with what the mechanism based on Install_Private_Declarations
& Uninstall_Declarations does for them, and this discrepancy runs afoul
of a nesting issue in Instantiate_Package_Body.
The issue is essentially only visible with inlining across units.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* sem_ch12.adb (Instantiate_Package_Body): Add commentary for a
nesting issue with parent handling and private view switching.
(Switch_View): Do not skip specific private-dependent subtypes.diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -12029,6 +12029,19 @@ package body Sem_Ch12 is
end if;
Restore_Hidden_Primitives (Vis_Prims_List);
+
+ -- Restore the private views that were made visible when the body of
+ -- the instantiation was created. Note that, in the case where one of
+ -- these private views is declared in the parent, there is a nesting
+ -- issue with the calls to Install_Parent and Remove_Parent made in
+ -- between above with In_Body set to True, because these calls also
+ -- want to swap and restore this private view respectively. In this
+ -- case, the call to Install_Parent does nothing, but the call to
+ -- Remove_Parent does restore the private view, thus undercutting the
+ -- call to Restore_Private_Views. That's OK under the condition that
+ -- the two mechanisms swap exactly the same entities, in particular
+ -- the private entities dependent on the primary private entities.
+
Restore_Private_Views (Act_Decl_Id);
-- Remove the current unit from visibility if this is an instance
@@ -16680,19 +16693,9 @@ package body Sem_Ch12 is
end if;
while Present (Priv_Elmt) loop
- Priv_Sub := (Node (Priv_Elmt));
-
- -- We avoid flipping the subtype if the Etype of its full view is
- -- private because this would result in a malformed subtype. This
- -- occurs when the Etype of the subtype full view is the full view of
- -- the base type (and since the base types were just switched, the
- -- subtype is pointing to the wrong view). This is currently the case
- -- for tagged record types, access types (maybe more?) and needs to
- -- be resolved. ???
-
- if Present (Full_View (Priv_Sub))
- and then not Is_Private_Type (Etype (Full_View (Priv_Sub)))
- then
+ Priv_Sub := Node (Priv_Elmt);
+
+ if Present (Full_View (Priv_Sub)) then
Prepend_Elmt (Full_View (Priv_Sub), Exchanged_Views);
Exchange_Declarations (Priv_Sub);
end if;
