[Qt-creator] Minimizing compile-time conditionals in Qt Creator

[Stephen Chu]

On 8/28/12 8:50 AM, Christian Kandeler wrote:
> On 28/08/12 14:19, ext Stephen Chu wrote:
>> On 8/28/12 3:56 AM, Christian Kandeler wrote:
>>>        QStringList rc(QLatin1String(".svn"));
>>>        if (Utils::HostOsInfo::isWindowsHost())
>>>            rc.push_back(QLatin1String("_svn"));
>>>        return rc;
>>
>> Doesn't this generate dead code that will never be executed on platforms
>> other than the intended one?
>
> Yes (with C++03 at least). And if you can provide an example where it
> demonstrably matters, we can switch back to ifdefs for that particular
> piece of code.

It's not just dead code. It's also the calling of the conditional 
function and the testing of it. These are all runtime cost that can and 
should be avoided.

Something like this in some frequently called function (string?) can 
impact the performance negatively.