Visual Studio 15.8.0 and Qt 5.11.1 does not compile (QRandom/std::aligned_storage)

sophonet

After upgrading to Visual Studio 15.8.0, Qt 5.11.1 does not compile anymore but breaks when compiling QRandom.cpp, since the update introduces a fix which is ABI-incompatible to previous versions (https://developercommunity.visualstudio.com/content/problem/274945/stdmake-shared-is-not-honouring-alignment-of-a.html).

My solution was to add a flag _ENABLE_EXTENDED_ALIGNED_STORAGE to both qtbase/mkspecs/common/msvc-desktop.conf (line 19) as well as qtbase/qmake/Makefile.win32 (line 42).

Is this the correct approach? Will this be added as a fix to mainline? Or is there a better solution?

Thanks, sophonet

BugCrasher

Hello sophonet,

I also have today compile Problems with the new 15.8.0 Update and Qt 5.9.5. I wrote the topic: "Problem with new Visual Studio update 2017 Version 15.8.0 and Qt 5.9.5". Maybe these are similar problems?

Greetings,
Matthias

sophonet

Hello Matthias,

to me, the problems do not see related. After having applied the fix described above (about which I am not sure whether it is the best), I could successfully compile Qt, without the problem you have mentioned (different Qt version)?

Best, sophonet

SGaist

Hi and welcome to devnet,

Please take a look at this thread about VS 15.8 on the development mailing list.

sophonet

Hi SGaist,

just had a look at the git repository. Indeed, the two proposed fixes appear almost exactly where I have suspected them to be. Thanks.

Best, sophonet

QMatthias

Hello @sophonet ,

thank you very much for your answer.
You are right. In the meantime, my problem with Qt 5.9.5 was solved:

[https://codereview.qt-project.org/#/c/236948/2/src/corelib/tools/qalgorithms.h](link url)

Many greetings from Germany,
Matthias