2017-10-27 20:22 GMT+02:00 Thiago Macieira <thiago.macie...@intel.com>: > On Friday, 27 October 2017 11:14:35 PDT Elvis Stansvik wrote: >> 2017-10-27 19:03 GMT+02:00 Thiago Macieira <thiago.macie...@intel.com>: >> > On Friday, 27 October 2017 09:43:57 PDT Elvis Stansvik wrote: >> >> Reentrant in the object oriented context of Qt means: It's safe to >> >> call member functions from different threads _if_ the calls are made >> >> on different instances. >> >> >> >> In your case you were making calls on the same instance. >> > >> > Calling const functions on the same instance is safe, provided no other >> > threads are calling non-const functions. >> > >> > He was calling a non-const function. >> >> Alright. Thanks for clarifying. Is that a guarantee that holds for all >> classes marked reentrant in Qt? (that const functions are safe even >> when called on the same instance) > > I can't say for sure. Most of them will be like that, and definitely all the > containers. > > There may be a few bugs here and there, code that does const_cast and needs to > be fixed. > >> If so, maybe the docs page I linked should be updated to mention this [1]. >> >> I thought that Qt wanted to reserve the right to do thread unsafe >> stuff even in const functions, and that was the reason for the >> definition of reentrant explained there. > > I will reject any change that tries to do that. But we may still have some of > them lying around. For example: > > https://github.com/qt/qt/blob/4.8/src/corelib/global/qglobal.h#L2088-L2090 >
Alright, yes it would of course be bad practice and you'll do right to reject such nonsense. Just wanted to give Jason a heads up that the definition of reentrant that's in Qt's docs does not guarantee it, even if it's very likely to be practically safe for the majority of classes. Elvis > -- > Thiago Macieira - thiago.macieira (AT) intel.com > Software Architect - Intel Open Source Technology Center > > _______________________________________________ > Interest mailing list > Interest@qt-project.org > http://lists.qt-project.org/mailman/listinfo/interest _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
