Error on initializing QByteArray

oliver_mpt

Hi,

I am porting an app from Qt 5.12.2 to Qt 6.5.0
The following lines are generating a crash in Qt6 while they posed no problem in Qt5

QByteArray qb;
qb[0] = 0; qb[1] = 0;

I have not found any indication in the documentation of the QByteArray class that its behaviour had been modified regarding this.

Any idea ?

SGaist

Hi,

It's explained in the operator documentation for Qt 5.15. And the behavior for Qt 6 is also explained in the corresponding operator documentation.

Your code ~~will~~ might already crash with 5.15.

oliver_mpt

Hi SGaist

Thanks for your help. Believe me, this code is working in 5.15.2 every day.
I'll read the doc carefully

Christian Ehrlicher

@oliver_mpt said in Error on initializing QByteArray:

Believe me, this code is working in 5.15.2 every day.

But it may crash tomorrow since it's undefined behavior.

SGaist

@oliver_mpt my bad, wrong verb. I meant to write: might already crash. But luckily it's not.

In any case, as the warning suggests, do not rely on such a behaviour.

oliver_mpt

Thanks SGaist and Christian
I'll rewrite that code cleanly :-)

SGaist

You're welcome !

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