Re: fyi, GNAT and SPARK GPL 2016 are out

[gautier_niouzes@hotmail.com]

Nice release - with new optimizations in the run-time library... and a nice banana skin. In some cases, an application working well with GNAT for years may crash with a nasty raised PROGRAM_ERROR : EXCEPTION_ACCESS_VIOLATION - but only in a typical release mode; in a typical debug mode it works as before.

In a nutshell, if you are using Ada.Containers.*Maps, and have code like the P_KO procedure below, which is legal Ada 2005 & 2012, the executable will bomb when built with the -gnatp switch.

The cure is to use a cursor like in P_OK. It removes an exception part as well.

Is there an inclusion of pragma Suppress(Container_Checks) into the standard on its way ? Then the remarks such as A.18.4, 69/2 could be updated accordingly.
_________________________ 
Gautier's Ada programming 
http://gautiersblog.blogspot.com/search/label/Ada 
NB: follow the above link for a valid e-mail address 

-----------8<-----------8<-----------8<-----------8<-------

--  GNAT GPL 2016 pragma, suppression included in -gnatp switch
pragma Suppress(Container_Checks); 

with Ada.Strings.Unbounded.Hash;             use Ada.Strings.Unbounded;
with Ada.Containers.Hashed_Maps;
with Ada.Text_IO; use Ada.Text_IO;

procedure Test_2016 is

  package T_Dic is new Ada.Containers.Hashed_Maps
    (Key_Type        => Ada.Strings.Unbounded.Unbounded_String,
     Element_Type    => Positive,
     Hash            => Ada.Strings.Unbounded.Hash,
     Equivalent_Keys => Ada.Strings.Unbounded."=");
  
  dic: T_Dic.Map;
  n: Positive:= 1;
  
  procedure P_KO(s: String) is
    i: Integer;
  begin
    i:= dic.Element(To_Unbounded_String(s));
    Put_Line("Key found, element=" & Integer'Image(i));
  exception
    when Constraint_Error =>  --  A.18.4, 69/2
      Put_Line("Key not found");
      dic.Insert(To_Unbounded_String(s), n);
      n:= n + 1;
  end P_KO;
  
  procedure P_OK(s: String) is
    i: Integer;
    use T_Dic;
    curs: Cursor;
  begin
    curs:= dic.Find(To_Unbounded_String(s));
    if curs = No_Element then
      Put_Line("Key not found");
      dic.Insert(To_Unbounded_String(s), n);
      n:= n + 1;
    else
      i:= Element(curs);
      Put_Line("Key found, element=" & Integer'Image(i));
    end if;
  end P_OK;

begin
  P_OK("A");
  P_OK("A");
  P_KO("B");
  P_KO("B");
end;