Re: [PATCH v5 2/8] GDB/Python: Use None for `var_zuinteger_unlimited' value set to `unlimited'

[Andrew Burgess <aburgess@redhat.com>]

"Maciej W. Rozycki" <macro@embecosm.com> writes:

> Consistently with the `var_integer' and `var_uinteger' parameters return 
> the special value of None for a `var_zuinteger_unlimited' parameter set 
> to `unlimited' by using the Py_RETURN_NONE macro in this case, fixing 
> commit 0489430a0e1a ("Handle var_zuinteger and var_zuinteger_unlimited 
> from Python"); cf. PR python/20084.  Adjust the testsuite
> accordingly.

Unfortunately, nice as it would be to make this change (for
consistency), I think we're stuck with what we have.

The -1 behaviour is documented for PARAM_ZUINTEGER_UNLIMITED in the
manual so it is not unreasonable to assume that there could be code in
the wild that relies on the existing behaviuor.

Thanks,
Andrew




> ---
> No change from v4.
>
> New change in v4.
> ---
>  gdb/python/python.c                       |   10 +++++++++-
>  gdb/testsuite/gdb.python/py-parameter.exp |    4 ++--
>  2 files changed, 11 insertions(+), 3 deletions(-)
>
> gdb-python-var-zuinteger-unlimited-none.diff
> Index: src/gdb/python/python.c
> ===================================================================
> --- src.orig/gdb/python/python.c
> +++ src/gdb/python/python.c
> @@ -507,9 +507,17 @@ gdbpy_parameter_value (const setting &va
>  	Py_RETURN_NONE;
>        /* Fall through.  */
>      case var_zinteger:
> -    case var_zuinteger_unlimited:
>        return gdb_py_object_from_longest (var.get<int> ()).release ();
>  
> +    case var_zuinteger_unlimited:
> +      {
> +	int val = var.get<int> ();
> +
> +	if (val == -1)
> +	  Py_RETURN_NONE;
> +	return gdb_py_object_from_longest (val).release ();
> +      }
> +
>      case var_uinteger:
>        {
>  	unsigned int val = var.get<unsigned int> ();
> Index: src/gdb/testsuite/gdb.python/py-parameter.exp
> ===================================================================
> --- src.orig/gdb/testsuite/gdb.python/py-parameter.exp
> +++ src/gdb/testsuite/gdb.python/py-parameter.exp
> @@ -343,8 +343,8 @@ proc_with_prefix test_integer_parameter
>  	} elseif {$kind == "PARAM_ZUINTEGER_UNLIMITED"} {
>  	    gdb_test_no_output "python test_param_$kind.value = -1" \
>  		"check that PARAM_ZUINTEGER value can be set to -1"
> -	    gdb_test "python print(gdb.parameter('test-$kind'))" "-1" \
> -		"check that PARAM_ZUINTEGER value is -1 after setting"
> +	    gdb_test "python print(gdb.parameter('test-$kind'))" "None" \
> +		"check that PARAM_ZUINTEGER value is None after setting"
>  	} else {
>  	    error "invalid kind: $kind"
>  	}