crash printing optimized out variant type
authorJoel Brobecker <brobecker@gnat.com>
Mon, 10 Sep 2012 22:18:24 +0000 (22:18 +0000)
committerJoel Brobecker <brobecker@gnat.com>
Mon, 10 Sep 2012 22:18:24 +0000 (22:18 +0000)
commit2fa15f237df903f4809733afee950f955559fbf7
tree8109b0e1d5c94615c476fcfc18fc294885c2b76d
parent5152ff903945c2e68714d562206030a703cc80c2
crash printing optimized out variant type

Assuming the following declarations:

   type Discriminants_Record (A : Integer; B : Boolean) is record
      C : Float;
   end record;
   Z : Discriminants_Record := (A => 1, B => False, C => 2.0);

If variable Z is not used, and the compiler optimizes it out,
GDB would crash as follow:

    (gdb) print Z
    /[...]/gdb/valops.c:1121: internal-error: Unexpected lazy value type.

This is because the ada-lang module forgot to set the optimized_out
flag in the value returned by ada_evaluate_subexp during the value's
"fixing" process.  Later on, when trying to print the resulting value,
GDB finds that the value is still lazily allocated, and thus tries to
fetch it. But this is not allowed for not_lval values, hence the internal
error.

gdb/ChangeLog:

        * ada-lang.c (coerce_unspec_val_to_type): Make sure that
        the optimized_out flag is preserved.

gdb/testsuite/ChangeLog:

        * gdb.ada/optim_drec: New testcase.
gdb/ChangeLog
gdb/ada-lang.c
gdb/testsuite/ChangeLog
gdb/testsuite/gdb.ada/optim_drec.exp [new file with mode: 0644]
gdb/testsuite/gdb.ada/optim_drec/foo.adb [new file with mode: 0644]