[Development] Proposing CMake as build tool for Qt 6

Konstantin Tokarev annulen at yandex.ru
Mon Jun 17 18:00:20 CEST 2019

17.06.2019, 18:43, "Thiago Macieira" <thiago.macieira at intel.com>:
> On Monday, 17 June 2019 08:16:38 PDT Konstantin Tokarev wrote:
>>  17.06.2019, 18:15, "Thiago Macieira" <thiago.macieira at intel.com>:
>>  > On Monday, 17 June 2019 02:52:03 PDT Konstantin Tokarev wrote:
>>  >> I think that automatic generation of PCH is a bad idea, leading to
>>  >> wasting
>>  >> build time.
>>  >
>>  > Like we do in Qt today?
>>  Yep. Approach of Qt Creator is much better.
> Elaborate, please.

Qt Creator uses manually crafted precompiled header files [1,2], which include
only those headers which are often used across the project. If you pull all public
headers of used Qt modules into pch like it was a kitchen sink, you spend a lot of
extra time precompiling stuff which wiould be used once or twice. It also increases
size of binary representation of PCH, and might make compilation slower because
compiler now has to do lookups in larger AST.

[1] https://code.qt.io/cgit/qt-creator/qt-creator.git/tree/src/shared/qtcreator_pch.h
[2] https://code.qt.io/cgit/qt-creator/qt-creator.git/tree/src/shared/qtcreator_gui_pch.h


More information about the Development mailing list