Because we have strawberry perl's bin dir in the PATH, CMake considers
that a find_package prefix, and thus finds includes and libraries
that are shipped with strawberry perl.
That causes problems because the 3rd party runtime libraries are not
installed by the Qt installer, so any Qt modules / plugins that depend
on the 3rd party libraries will fail to load.
Use CMake 3.23's CMAKE_IGNORE_PREFIX_PATH option to tell it to ignore
strawberry headers and libraries.
We need to repeat it both for qtbase and non-qtbase args, to ensure
the libraries are not picked up for all of Qt.
This is a more general fix for problems like the one fixed by
a97bdde4d4
Pick-to: 6.5 6.6
Task-number: QTBUG-113726
Change-Id: I706bf9ac945a47dc809bbb6eb9eda4ca93f84695
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
HOW TO BUILD Qt 6
Synopsis
System requirements
- C++ compiler supporting the C++17 standard
- CMake
- Ninja
- Python 3
For more details, see also https://doc.qt.io/qt-6/build-sources.html
Linux, Mac:
cd <path>/<source_package>
./configure -prefix $PWD/qtbase
cmake --build .
Windows:
- Open a command prompt.
- Ensure that the following tools can be found in the path:
- Supported compiler (Visual Studio 2019 or later, or MinGW-builds gcc 8.1 or later)
- Python 3 ([https://www.python.org/downloads/windows/] or from Microsoft Store)
cd <path>\<source_package>
configure -prefix %CD%\qtbase
cmake --build .
More details follow.
Build!
Qt is built with CMake, and a typical
configure && cmake --build . build process is used.
If Ninja is installed, it is automatically chosen as CMake generator.
Some relevant configure options (see configure -help):
-releaseCompile and link Qt with debugging turned off.-debugCompile and link Qt with debugging turned on.
Example for a release build:
./configure -prefix $PWD/qtbase
cmake --build .
Example for a developer build: (enables more autotests, builds debug version of libraries, ...)
./configure -developer-build
cmake --build .
See output of ./configure -help for documentation on various options to
configure.
The above examples will build whatever Qt modules have been enabled by default in the build system.
It is possible to build selected repositories with their dependencies by doing
a ninja <repo-name>/all. For example, to build only qtdeclarative,
and the modules it depends on:
./configure
ninja qtdeclarative/all
This can save a lot of time if you are only interested in a subset of Qt.
Hints
The submodule repository qtrepotools contains useful scripts for
developers and release engineers. Consider adding qtrepotools/bin
to your PATH environment variable to access them.
Building Qt from git
See http://wiki.qt.io/Building_Qt_6_from_Git and README.git for more information. See http://wiki.qt.io/Qt_6 for the reference platforms.
Documentation
After configuring and compiling Qt, building the documentation is possible by running
cmake --build . --target docs
After having built the documentation, you need to install it with the following command:
cmake --build . --target install_docs
The documentation is installed in the path specified with the
configure argument -docdir.
Information about Qt's documentation is located in qtbase/doc/README
Note: Building the documentation is only tested on desktop platforms.