The compiler is trying to instantiate a generic body for an instantiation
present in a transient package that it has discarded.
Tested on x86-64/Linux, applied on the mainline and 16 branch.
2026-08-19 Eric Botcazou <[email protected]>
PR ada/126928
* sem_ch12.adb (In_Local_Package_Of_Formal_Package): New predicate.
(Analyze_Package_Instantiation): Do not register the instantiation
of the body if it is present in the local package of a formal one.
(Need_Subprogram_Instance_Body): Likewise.
2026-08-19 Eric Botcazou <[email protected]>
* gnat.dg/specs/generic_inst10.ads: New test.
* gnat.dg/specs/generic_inst10_g1.ads: New helper.
* gnat.dg/specs/generic_inst10_g2.ads: Likewise.
* gnat.dg/specs/generic_inst10_g3.ads: Likewise.
* gnat.dg/specs/generic_inst10_pkg.ads: Likewise.
--
Eric Botcazou
diff --git a/gcc/ada/sem_ch12.adb b/gcc/ada/sem_ch12.adb
index e2be3f59f25..a87dde1868b 100644
--- a/gcc/ada/sem_ch12.adb
+++ b/gcc/ada/sem_ch12.adb
@@ -776,6 +776,11 @@ package body Sem_Ch12 is
-- not done for the instantiation of the bodies, which only require the
-- instances of the generic parents to be in scope.
+ function In_Local_Package_Of_Formal_Package (N : Node_Id) return Boolean;
+ -- Return whether N is present in the local package created during the
+ -- analysis of a formal package (see Analyze_Formal_Package_Declaration).
+ -- Used to avoid instantiating generic bodies in such a local package.
+
function In_Main_Context (E : Entity_Id) return Boolean;
-- Check whether an instantiation is in the context of the main unit.
-- Used to determine whether its body should be elaborated to allow
@@ -5438,6 +5443,7 @@ package body Sem_Ch12 is
and then Needs_Body_Instantiated (Gen_Unit)
and then not Is_Abbrev
and then not Inline_Now
+ and then not In_Local_Package_Of_Formal_Package (N)
and then (Operating_Mode = Generate_Code
or else (Operating_Mode = Check_Semantics
and then GNATprove_Mode));
@@ -6592,6 +6598,10 @@ package body Sem_Ch12 is
and then (not Is_Generic_Unit (Cunit_Entity (Main_Unit))
or else Parent (N) = Aux_Decls_Node (Cunit (Main_Unit)))
+ -- Likewise in the local package built for formal packages
+
+ and then not In_Local_Package_Of_Formal_Package (N)
+
-- Must be generating code or analyzing code in GNATprove mode
and then (Operating_Mode = Generate_Code
@@ -11285,6 +11295,26 @@ package body Sem_Ch12 is
(Current_Scope, Current_Scope, Assoc_Null);
end Init_Env;
+ ----------------------------------------
+ -- In_Local_Package_Of_Formal_Package --
+ ----------------------------------------
+
+ function In_Local_Package_Of_Formal_Package (N : Node_Id) return Boolean is
+ Par : Node_Id;
+
+ begin
+ Par := Parent (N);
+ while Present (Par) and then Nkind (Par) /= N_Compilation_Unit loop
+ if Nkind (Original_Node (Par)) = N_Formal_Package_Declaration then
+ return True;
+ end if;
+
+ Par := Parent (Par);
+ end loop;
+
+ return False;
+ end In_Local_Package_Of_Formal_Package;
+
---------------------
-- In_Main_Context --
---------------------
with Generic_Inst10_G3;
with Generic_Inst10_Pkg;
package Generic_Inst10 is new Generic_Inst10_G3 (Generic_Inst10_Pkg);
generic
package Generic_Inst10_G1 is
end Generic_Inst10_G1;
with Ada.Containers.Indefinite_Ordered_Maps;
with Generic_Inst10_G1;
generic
package Generic_Inst10_G2 is
generic
with package Actual_Types is new Generic_Inst10_G1;
package Holder is
private
package Maps is new Ada.Containers.Indefinite_Ordered_Maps
(Integer, Integer);
end Holder;
generic
with package Actual_Types is new Generic_Inst10_G1;
with package Actual_Holder is new Holder (Actual_Types);
package User is
end User;
generic
with package Actual_Types is new Generic_Inst10_G1;
with package Actual_User is
new User (Actual_Types => Actual_Types, others => <>);
package Final is
end Final;
end Generic_Inst10_G2;
with Generic_Inst10_G1;
with Generic_Inst10_G2;
generic
with package Actual_Types is new Generic_Inst10_G1;
package Generic_Inst10_G3 is
package Actual_Root is new Generic_Inst10_G2;
package Actual_Holder is new Actual_Root.Holder (Actual_Types);
package Actual_User is new
Actual_Root.User (Actual_Types, Actual_Holder);
package Actual_Final is new
Actual_Root.Final (Actual_Types, Actual_User);
end Generic_Inst10_G3;
with Generic_Inst10_G1;
package Generic_Inst10_Pkg is new Generic_Inst10_G1;
