[Development] QVariant and types with throwing dtors

[Marc Mutz]

On 26.08.24 08:43, Ville Voutilainen wrote:
>> IMHO, (1) is not an acceptable option. Us C++ professionals having identified
>> this problem after years of it lying dormant, it behooves us, at the
>> very least, to educate our users about this, e.g. by adding docs, and
>> maybe a qWarning() in ~QVariant(), if we don't do (2).
> 
> If it's not an issue, why is (1) unacceptable?

It's _guesstimated_ to be no issue, based on sampling qt5.git and 
qt-creator.git.

What is unacceptable in (1) (doing nothing) is not even _informing_ 
users about what we found¹, so _they_ can decide for themselves what to do.

¹ neither at compile-time, nor runtime, nor coding time (static checker)
   nor at documentation reading time.

We want our APIs to be easy to use and hard to abuse. It's easy to abuse 
QVariant in this way, so it behooves us to try to do _something_ about it.

Thanks,
Marc

-- 
Marc Mutz <marc.mutz at qt.io> (he/his)
Principal Software Engineer

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