17.06.2019, 12:48, "Mark De Wit" <mark.de...@iesve.com>: >> -----Original Message----- >> From: Development <development-boun...@qt-project.org> On Behalf Of >> Konstantin Tokarev >> Sent: 06 June 2019 14:30 >> To: Simon Hausmann <simon.hausm...@qt.io>; Bogdan Vatra >> <bogdan.va...@kdab.com>; development@qt-project.org >> Subject: Re: [Development] Proposing CMake as build tool for Qt 6 >> >> 06.06.2019, 16:25, "Simon Hausmann" <simon.hausm...@qt.io>: >> > Hi, >> > >> > Regarding PCH, it seems that right now it would be easiest to include >> something like https://github.com/sakra/cotire . Patches are welcome to >> integrate this or alternatively work with upstream CMake for a built-in >> solution. >> >> Yet another alternative is https://github.com/larsch/cmake-precompiled- >> header/blob/master/PrecompiledHeader.cmake >> which is not so monstrous as cotire > > I have used Cotire until recently and would caution against it. The library > at its core is a clever idea but its implementation caused a lot of build > instability for us. Its current version doesn't work on MSVC with CMake > > 3.12, also fails on Mac with AppleClang 8.0 (bad command line parameter). It > appears to be unmaintained as my bug reports have gone completely unanswered > / not even acknowledged. > > In the end I wrote my own pch script that works ok for our scenario. MSVC > support is pretty trivial, gcc/clang more awkward because their pch > compilation is a separate build step. My script did include some ideas from > larsch github repo linked above, but I don't like his approach of injecting > build flags into the clang/gcc pch stage (it didn't work for me, I ended up > missing critical flags). > > I used some ideas from cotire to generate a list of includes to seed each > module PCH header file, but maintain updates manually (like MSVC > stdafx.h/pch.h approach). I'm sure pch header generation could be automated > too...
I think that automatic generation of PCH is a bad idea, leading to wasting build time. -- Regards, Konstantin _______________________________________________ Development mailing list Development@qt-project.org https://lists.qt-project.org/listinfo/development
