[Bug ada/70867] New: access discriminant in return aggregate detected as dangling if set from an implicit dereference in generic package

["nicolas.boulenguez at free dot fr" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70867

            Bug ID: 70867
           Summary: access discriminant in return aggregate detected as
                    dangling if set from an implicit dereference in
                    generic package
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: ada
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nicolas.boulenguez at free dot fr
  Target Milestone: ---

Hello.
With GCC-6 (Debian 6.0.1-2) 6.0.1 20160423 (prerelease),
compiling the following package with "gcc-6 -c p.adb" fails:
p.adb:4:20: access discriminant in return aggregate would be a dangling
reference
The code compiles
- if the "generic" line is removed
- or if ".all" is inserted between "Position" and ".Item'Access"
I am not sure whether returning this reference is allowed by the Ada Reference
Manual,
but the semantics of "generic" and ".all" should certainly not affect the
answer.

-- Content of p.ads.
generic                                                                        
package P is                                                                   
   type T (D : access Integer) is null record;                                 
   type R is record                                                            
      Item : aliased Integer;                                                  
   end record;                                                                 
   function F (Position : access R) return T;                                  
end P;                                                                         
-- Content of p.adb.
package body P is                                                              
   function F (Position : access R) return T is                                
   begin                                                                       
      return (D => Position.Item'Access);                                      
   end F;                                                                      
end P;