gdb/testsuite/gdb.ada/packed_tagged/comp_bug.adb

   1 --  Copyright 2008-2021 Free Software Foundation, Inc.
   2 --
   3 --  This program is free software; you can redistribute it and/or modify
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   5 --  the Free Software Foundation; either version 3 of the License, or
   6 --  (at your option) any later version.
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   8 --  This program is distributed in the hope that it will be useful,
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  10 --  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 --  GNU General Public License for more details.
  12 --
  13 --  You should have received a copy of the GNU General Public License
  14 --  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15
  16 procedure Comp_Bug is
  17
  18    type Number_T (Exists : Boolean := False) is
  19       record
  20          case Exists is
  21             when True =>
  22                Value : Natural range 0 .. 255;
  23             when False =>
  24                null;
  25          end case;
  26       end record;
  27    pragma Pack (Number_T);
  28
  29    X : Number_T;
  30    --  brobecker/2007-09-06: At the time when this issue (G904-017) was
  31    --  reported, the problem only reproduced if the variable was declared
  32    --  inside a function (in other words, stored on stack).  Although
  33    --  the issue probably still existed when I tried moving this variable
  34    --  to a package spec, the symptoms inside GDB disappeared.
  35 begin
  36    X := (Exists => True, Value => 10);
  37    if X.Exists then -- STOP
  38       X.Value := X.Value + 1;
  39    end if;
  40 end Comp_Bug;