[Development] HEADS UP: Don't use QList, use Q_DECLARE_TYPEINFO

Matthew Woehlke mwoehlke.floss at gmail.com
Mon Aug 10 16:52:58 CEST 2015

On 2015-08-09 07:58, Kevin Kofler wrote:
> Thiago Macieira wrote:
>> Please see the C++17 proposal of destructive moves instead.
> It took 4 years for Qt to agree to require a limited subset of C++11, so, 
> realistically, C++17 features are not likely to end up used (everywhere, at 
> least) before at least 2021.
> I guess it will also require good compiler optimization to be as effective 
> as a memmove operating on the whole vector. (Basically, the compiler needs 
> to detect that you are memmoving a whole vector and convert it to a 
> memmove.)

Please *see* the proposal. The major point is to have the ability to
mark such as defaulted, and to detect when it is *trivial*. When its
trivial, containers can use memmove/realloc/etc. instead of copying.

(It's not clear yet if they will do so directly, or via some helper, but
that shouldn't matter performance-wise.)


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