Re: [PATCH 2/2] serial: cascade needless conditionals

[André Goddard Rosa]

Hi, Henrique!

On 10/25/09, Henrique de Moraes Holschuh <hmh@xxxxxxxxxx> wrote:
> On Sun, 25 Oct 2009, André Goddard Rosa wrote:
>>  	if (flags == UPF_SPD_HI)
>>  		altbaud = 57600;
>> -	if (flags == UPF_SPD_VHI)
>> +	else if (flags == UPF_SPD_VHI)
>>  		altbaud = 115200;
>> -	if (flags == UPF_SPD_SHI)
>> +	else if (flags == UPF_SPD_SHI)
>>  		altbaud = 230400;
>> -	if (flags == UPF_SPD_WARP)
>> +	else if (flags == UPF_SPD_WARP)
>>  		altbaud = 460800;
>
> This changes code behaviour if more than one bit is set (which might never
> happen for all I know...).  You should invert the order of the tests if you
> want to make sure it is side-effect-free.
>

Do you mind explaining why? Notice that it's not (var & flag), it's =='.
Can flags be equal more than one flag at the same time?

Thanks,
André
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