Re: [Qemu-devel] [PATCH 7/9] openpic: avoid a warning from clang analyzer

[Blue Swirl]

On Mon, Sep 5, 2011 at 6:48 AM, Paolo Bonzini <address@hidden> wrote:
> On 09/04/2011 05:52 PM, Blue Swirl wrote:
>>
>> Avoid this warning by clang analyzer by defining a default case:
>> /src/qemu/hw/openpic.c:477:5: warning: Undefined or garbage value
>> returned to caller
>>     return retval;
>>
>> Signed-off-by: Blue Swirl<address@hidden>
>> ---
>>  hw/openpic.c |    1 +
>>  1 files changed, 1 insertions(+), 0 deletions(-)
>>
>> diff --git a/hw/openpic.c b/hw/openpic.c
>> index 26c96e2..4b883ac 100644
>> --- a/hw/openpic.c
>> +++ b/hw/openpic.c
>> @@ -469,6 +469,7 @@ static inline uint32_t read_IRQreg (openpic_t
>> *opp, int n_IRQ, uint32_t reg)
>>      case IRQ_IPVP:
>>          retval = opp->src[n_IRQ].ipvp;
>>          break;
>> +    default:
>>      case IRQ_IDE:
>>          retval = opp->src[n_IRQ].ide;
>>          break;
>
> Looks wrong, perhaps it should return 0?

The only possible values are IRQ_IDE and IRQ_IPVP.

The function is actually baroque, it's as easy to use
read_IRQreg(opp, IRQ_DBL0 + n_dbl, IRQ_IPVP);
as the shorter
opp->src[IRQ_DBL0 + n_dbl].ipvp;

The reason seems to be that write_IRQreg is more complex. I'd replace
both with {read,write}_{ide,ipvp} without the switch.