Re: [RFA] Fix crash of convenience vars with typedefs.

[Doug Evans <dje at google dot com>]

On Mon, Aug 17, 2009 at 11:16 AM, Ulrich Weigand<uweigand@de.ibm.com> wrote:
> I wrote:
>> Maybe it would be best to split the INTERNALVAR_SCALAR state into two
>> distinct states INTERNALVAL_INTEGER and INTERNAL_POINTER; the decision
>> can be make in set_internalvar, where we already call check_typedef,
>> and then used subsequentially.
>
> Like so. ?Does this fix your problem?


Almost.  gdb now crashes in a different place.

[from testsuite/gdb.log]
print /x $prog_var
../../../src/gdb/findvar.c:246: internal-error: store_typed_address:
type is not a pointer or reference
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) FAIL: gdb.base/gdbvars.exp:
Print contents of new convenience variable of program variable (GDB
internal error)
n
../../../src/gdb/findvar.c:246: internal-error: store_typed_address:
type is not a pointer or reference
A problem internal to GDB has been detected,
further debugging may prove unreliable.


Can you run the testcase included in my patch?
If that passes I'm happy.


>
> Bye,
> Ulrich
>
>
> ChangeLog:
>
> ? ? ? ?* value.c (enum internalvar_kind): Replace INTERNALVAR_SCALAR by
> ? ? ? ?INTERNALVAR_INTEGER and INTERNALVAR_POINTER.
> ? ? ? ?(union internalvar_data): Replace "scalar" member by "integer"
> ? ? ? ?and "pointer".
> ? ? ? ?(value_of_internalvar): Handle INTERNALVAR_INTEGER and
> ? ? ? ?INTERNALVAR_POINTER instead of INTERNALVAR_SCALAR.
> ? ? ? ?(get_internalvar_integer): Likewise.
> ? ? ? ?(set_internalvar): Likewise.
> ? ? ? ?(set_internalvar_integer): Likewise.
> ? ? ? ?(preserve_one_internalvar): Likewise.
>
>
> Index: gdb/value.c
> ===================================================================
> RCS file: /cvs/src/src/gdb/value.c,v
> retrieving revision 1.92
> diff -u -p -r1.92 value.c
> --- gdb/value.c 13 Aug 2009 18:39:20 -0000 ? ? ?1.92
> +++ gdb/value.c 17 Aug 2009 17:06:30 -0000
> @@ -920,8 +920,11 @@ struct internalvar
> ? ? ? /* The internal variable holds a GDB internal convenience function. ?*/
> ? ? ? INTERNALVAR_FUNCTION,
>
> - ? ? ?/* The variable holds a simple scalar value. ?*/
> - ? ? ?INTERNALVAR_SCALAR,
> + ? ? ?/* The variable holds an integer value. ?*/
> + ? ? ?INTERNALVAR_INTEGER,
> +
> + ? ? ?/* The variable holds a pointer value. ?*/
> + ? ? ?INTERNALVAR_POINTER,
>
> ? ? ? /* The variable holds a GDB-provided string. ?*/
> ? ? ? INTERNALVAR_STRING,
> @@ -944,19 +947,22 @@ struct internalvar
> ? ? ? ? ?int canonical;
> ? ? ? ?} fn;
>
> - ? ? ?/* A scalar value used with INTERNALVAR_SCALAR. ?*/
> + ? ? ?/* An integer value used with INTERNALVAR_INTEGER. ?*/
> ? ? ? struct
> ? ? ? ? {
> ? ? ? ? ?/* If type is non-NULL, it will be used as the type to generate
> ? ? ? ? ? ? a value for this internal variable. ?If type is NULL, a default
> ? ? ? ? ? ? integer type for the architecture is used. ?*/
> ? ? ? ? ?struct type *type;
> - ? ? ? ? union
> - ? ? ? ? ? {
> - ? ? ? ? ? ? LONGEST l; ? ?/* Used with TYPE_CODE_INT and NULL types. ?*/
> - ? ? ? ? ? ? CORE_ADDR a; ?/* Used with TYPE_CODE_PTR types. ?*/
> - ? ? ? ? ? } val;
> - ? ? ? ?} scalar;
> + ? ? ? ? LONGEST val;
> + ? ? ? ?} integer;
> +
> + ? ? ?/* A pointer value used with INTERNALVAR_POINTER. ?*/
> + ? ? ?struct
> + ? ? ? ?{
> + ? ? ? ? struct type *type;
> + ? ? ? ? CORE_ADDR val;
> + ? ? ? ?} pointer;
>
> ? ? ? /* A string value used with INTERNALVAR_STRING. ?*/
> ? ? ? char *string;
> @@ -1082,16 +1088,16 @@ value_of_internalvar (struct gdbarch *gd
> ? ? ? val = allocate_value (builtin_type (gdbarch)->internal_fn);
> ? ? ? break;
>
> - ? ?case INTERNALVAR_SCALAR:
> - ? ? ?if (!var->u.scalar.type)
> + ? ?case INTERNALVAR_INTEGER:
> + ? ? ?if (!var->u.integer.type)
> ? ? ? ?val = value_from_longest (builtin_type (gdbarch)->builtin_int,
> - ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? var->u.scalar.val.l);
> - ? ? ?else if (TYPE_CODE (var->u.scalar.type) == TYPE_CODE_INT)
> - ? ? ? val = value_from_longest (var->u.scalar.type, var->u.scalar.val.l);
> - ? ? ?else if (TYPE_CODE (var->u.scalar.type) == TYPE_CODE_PTR)
> - ? ? ? val = value_from_pointer (var->u.scalar.type, var->u.scalar.val.a);
> + ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? var->u.integer.val);
> ? ? ? else
> - ? ? ? ?internal_error (__FILE__, __LINE__, "bad type");
> + ? ? ? val = value_from_longest (var->u.integer.type, var->u.integer.val);
> + ? ? ?break;
> +
> + ? ?case INTERNALVAR_POINTER:
> + ? ? ?val = value_from_pointer (var->u.pointer.type, var->u.pointer.val);
> ? ? ? break;
>
> ? ? case INTERNALVAR_STRING:
> @@ -1145,14 +1151,9 @@ get_internalvar_integer (struct internal
> ?{
> ? switch (var->kind)
> ? ? {
> - ? ?case INTERNALVAR_SCALAR:
> - ? ? ?if (var->u.scalar.type == NULL
> - ? ? ? ? || TYPE_CODE (var->u.scalar.type) == TYPE_CODE_INT)
> - ? ? ? {
> - ? ? ? ? *result = var->u.scalar.val.l;
> - ? ? ? ? return 1;
> - ? ? ? }
> - ? ? ?/* Fall through. ?*/
> + ? ?case INTERNALVAR_INTEGER:
> + ? ? ?*result = var->u.integer.val;
> + ? ? ?return 1;
>
> ? ? default:
> ? ? ? return 0;
> @@ -1224,15 +1225,15 @@ set_internalvar (struct internalvar *var
> ? ? ? break;
>
> ? ? case TYPE_CODE_INT:
> - ? ? ?new_kind = INTERNALVAR_SCALAR;
> - ? ? ?new_data.scalar.type = value_type (val);
> - ? ? ?new_data.scalar.val.l = value_as_long (val);
> + ? ? ?new_kind = INTERNALVAR_INTEGER;
> + ? ? ?new_data.integer.type = value_type (val);
> + ? ? ?new_data.integer.val = value_as_long (val);
> ? ? ? break;
>
> ? ? case TYPE_CODE_PTR:
> - ? ? ?new_kind = INTERNALVAR_SCALAR;
> - ? ? ?new_data.scalar.type = value_type (val);
> - ? ? ?new_data.scalar.val.a = value_as_address (val);
> + ? ? ?new_kind = INTERNALVAR_POINTER;
> + ? ? ?new_data.pointer.type = value_type (val);
> + ? ? ?new_data.pointer.val = value_as_address (val);
> ? ? ? break;
>
> ? ? default:
> @@ -1269,9 +1270,9 @@ set_internalvar_integer (struct internal
> ? /* Clean up old contents. ?*/
> ? clear_internalvar (var);
>
> - ?var->kind = INTERNALVAR_SCALAR;
> - ?var->u.scalar.type = NULL;
> - ?var->u.scalar.val.l = l;
> + ?var->kind = INTERNALVAR_INTEGER;
> + ?var->u.integer.type = NULL;
> + ?var->u.integer.val = l;
> ?}
>
> ?void
> @@ -1426,10 +1427,16 @@ preserve_one_internalvar (struct interna
> ?{
> ? switch (var->kind)
> ? ? {
> - ? ?case INTERNALVAR_SCALAR:
> - ? ? ?if (var->u.scalar.type && TYPE_OBJFILE (var->u.scalar.type) == objfile)
> - ? ? ? var->u.scalar.type
> - ? ? ? ? = copy_type_recursive (objfile, var->u.scalar.type, copied_types);
> + ? ?case INTERNALVAR_INTEGER:
> + ? ? ?if (var->u.integer.type && TYPE_OBJFILE (var->u.integer.type) == objfile)
> + ? ? ? var->u.integer.type
> + ? ? ? ? = copy_type_recursive (objfile, var->u.integer.type, copied_types);
> + ? ? ?break;
> +
> + ? ?case INTERNALVAR_POINTER:
> + ? ? ?if (TYPE_OBJFILE (var->u.pointer.type) == objfile)
> + ? ? ? var->u.pointer.type
> + ? ? ? ? = copy_type_recursive (objfile, var->u.pointer.type, copied_types);
> ? ? ? break;
>
> ? ? case INTERNALVAR_VALUE:
>
> --
> ?Dr. Ulrich Weigand
> ?GNU Toolchain for Linux on System z and Cell BE
> ?Ulrich.Weigand@de.ibm.com
>