Fix internal error on locally-defined subpools

If the type is derived in the current compilation unit, and Allocate
is not overridden on derivation (as is typically the case with
Root_Storage_Pool_With_Subpools), the entity for Allocate of the
derived type is an alias for System.Storage_Pools.Subpools.Allocate.

The main assertion in gnat_to_gnu_entity fails in this case, since
this is not a definition and Is_Public is false (since the entity
is nested in the same compilation unit).

2020-03-11  Richard Wai  <richard@annexi-strayline.com>

	* gcc-interface/decl.c (gnat_to_gnu_entity): Also test Is_Public on
	the Alias of the entitiy, if is present, in the main assertion.

gcc/ada/ChangeLog

@@ -1,3 +1,8 @@
+2020-03-11  Richard Wai  <richard@annexi-strayline.com>
+
+	* gcc-interface/decl.c (gnat_to_gnu_entity): Also test Is_Public on
+	the Alias of the entitiy, if is present, in the main assertion.
+
 2020-02-06  Alexandre Oliva <oliva@adacore.com>
 
 	* raise-gcc.c (personality_body) [__ARM_EABI_UNWINDER__]:

gcc/ada/gcc-interface/decl.c

@@ -446,7 +446,12 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
 
   /* If we get here, it means we have not yet done anything with this entity.
      If we are not defining it, it must be a type or an entity that is defined
-     elsewhere or externally, otherwise we should have defined it already.  */
+     elsewhere or externally, otherwise we should have defined it already.
+
+     One exception is for an entity, typically an inherited operation, which is
+     a local alias for the parent's operation.  It is neither defined, since it
+     is an inherited operation, nor public, since it is declared in the current
+     compilation unit, so we test Is_Public on the Alias entity instead.  */
   gcc_assert (definition
 	      || is_type
 	      || kind == E_Discriminant
@@ -454,6 +459,8 @@ gnat_to_gnu_entity (Entity_Id gnat_entity, tree gnu_expr, bool definition)
 	      || kind == E_Label
 	      || (kind == E_Constant && Present (Full_View (gnat_entity)))
 	      || Is_Public (gnat_entity)
+	      || (Present (Alias (gnat_entity))
+		  && Is_Public (Alias (gnat_entity)))
 	      || type_annotate_only);
 
   /* Get the name of the entity and set up the line number and filename of

gcc/testsuite/ChangeLog

@@ -1,3 +1,7 @@
+2020-03-11  Richard Wai  <richard@annexi-strayline.com>
+
+	* gnat.dg/subpools1.adb: New test.
+
 2020-03-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/94121

gcc/testsuite/gnat.dg/subpools1.adb

@@ -0,0 +1,82 @@
+-- { dg-do compile }
+
+with System.Storage_Elements;
+with System.Storage_Pools.Subpools;
+
+procedure Subpools1 is
+
+   use System.Storage_Pools.Subpools;
+
+   package Local_Pools is
+
+      use System.Storage_Elements;
+
+      type Local_Pool is new Root_Storage_Pool_With_Subpools with null record;
+
+      overriding
+      function Create_Subpool (Pool: in out Local_Pool)
+                               return not null Subpool_Handle;
+
+      overriding
+      procedure Allocate_From_Subpool
+        (Pool                    : in out Local_Pool;
+         Storage_Address         :    out System.Address;
+         Size_In_Storage_Elements: in     Storage_Count;
+         Alignment               : in     Storage_Count;
+         Subpool                 : in     not null Subpool_Handle);
+
+      overriding
+      procedure Deallocate_Subpool
+        (Pool   : in out Local_Pool;
+         Subpool: in out Subpool_Handle) is null;
+
+   end Local_Pools;
+
+   package body Local_Pools is
+
+      type Local_Subpool is new Root_Subpool with null record;
+
+      Dummy_Subpool: aliased Local_Subpool;
+
+      overriding
+      function Create_Subpool (Pool: in out Local_Pool)
+                               return not null Subpool_Handle 
+      is 
+      begin 
+         return Result: not null Subpool_Handle 
+           := Dummy_Subpool'Unchecked_Access
+         do
+            Set_Pool_Of_Subpool (Result, Pool);
+         end return;
+      end;
+
+      overriding
+      procedure Allocate_From_Subpool
+        (Pool                    : in out Local_Pool;
+         Storage_Address         :    out System.Address;
+         Size_In_Storage_Elements: in     Storage_Count;
+         Alignment               : in     Storage_Count;
+         Subpool                 : in     not null Subpool_Handle)
+      is
+         type Storage_Array_Access is access Storage_Array;
+
+         New_Alloc: Storage_Array_Access
+           := new Storage_Array (1 .. Size_In_Storage_Elements + Alignment);
+      begin
+         for SE of New_Alloc.all loop
+            Storage_Address := SE'Address;
+            exit when Storage_Address mod Alignment = 0;
+         end loop;
+      end;
+
+   end Local_Pools;
+
+   A_Pool: Local_Pools.Local_Pool;
+
+   type Integer_Access is access Integer with Storage_Pool => A_Pool;
+
+   X: Integer_Access := new Integer; 
+
+begin
+   null;
+end;