Hi Chris,
On 21 August 2017 at 13:26, Christopher Li <sparse@xxxxxxxxxxx> wrote:
> On Sun, Aug 20, 2017 at 6:16 PM, Luc Van Oostenryck
> <luc.vanoostenryck@xxxxxxxxx> wrote:
>> During the expansion of a dereference, it's if the initializer
>> which corrrespond to the offset we're interested is a constant.
>> In which case this dereference can be avoided and the value
>> given in the initializer can be used instead.
>>
>> However, it's not enough to check for the offset since for bitfields
>> several are placed at the same offset.
>> Currently, the first initializer matching the offset is selected.
>>
>> Fix this by refusing such expansion if the constant value correspond
>> to a bitfield.
>>
>
>> --- a/expand.c
>> +++ b/expand.c
>> @@ -644,6 +644,8 @@ static int expand_dereference(struct expression *expr)
>> if (value) {
>> /* FIXME! We should check that the size is right! */
>> if (value->type == EXPR_VALUE) {
>> + if (is_bitfield_type(value->ctype))
>> + return UNSAFE;
>
> You might want to consider move this outside of the EXPR_VALUE.
> I assume there is a bug in sparse matching the value to the member
> wrong, it could happen to EXPR_FVALUE as well.
>
Since a bitfield is always integer and this issue is occurring with
bitfields, then I guess this change is correct?
Regards
Dibyendu
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