qt5base-lts/CMakeLists.txt
Alexandru Croitor 72aab8b487 CMake: Bump the minimum required CMake version to build Qt to 3.18
Add a new function that returns the minimum CMake version required to
build Qt. Pass that value to cmake_minimum_required() when building
qtbase and its standalone tests.

The minimum supported CMake version is read from qtbase/.cmake.conf
and its value should be updated when the need arises. It's the main
source of truth for all repos.

Provide a way to lower the minimum CMake version at configure time by
passing a value via QT_FORCE_MIN_CMAKE_VERSION.
This is not an officially supported way of building Qt. If the
specified version is lower than Qt's supported minimum, show a
warning.

Nevertheless the option is useful for testing how Qt builds with a
different minimum CMake version due to different policies being
enabled by default.

Issue warnings for CMake versions that are higher than the minimum
version but are known to cause issues when building Qt.

A counterpart change is needed in qt5 to ensure the minimum CMake
version is set at the proper time for top-level builds.

Ideally we would use the same 'check the CMake minimum version` code
in all our repositories, but that will cause lots of duplication because
we can't really find_package() the code and doing something like
include(../qtbase/foo.cmake) hardcodes assumptions about repo
locations.

So for now we don't bump the minimum version in child repo
cmake_minimum_required calls (qtsvg, qtdeclarative, etc).
Instead we record both the minimum supported version and the computed
minimum version (in case a different version was forced) in
QtBuildInternalsExtra.cmake.
Then we require qtbase's computed min version in
qt_build_repo_begin().

This won't set policies as cmake_minimum_required would, but at least
it propagates what minimum CMake version should be used for child
repos.

We might still have to bump the versions in child repos at some point.

Task-number: QTBUG-88086
Change-Id: Ida1c0d5d3e0fbb15d2aee9b68abab7a1648774b9
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-11-03 13:06:14 +01:00

148 lines
5.3 KiB
CMake

# special case skip regeneration
# Get the repo version and the minimum CMake version.
include("${CMAKE_CURRENT_SOURCE_DIR}/.cmake.conf")
if(NOT QT_SUPER_BUILD)
include("${CMAKE_CURRENT_SOURCE_DIR}/cmake/QtCMakeVersionHelpers.cmake")
qt_internal_check_for_suitable_cmake_version()
qt_internal_get_computed_minimum_cmake_version(__qt_minimum_cmake_version)
cmake_minimum_required(VERSION ${__qt_minimum_cmake_version})
endif()
# Run auto detection routines, but not when doing standalone tests. In that case, the detection
# results are taken from either QtBuildInternals or the qt.toolchain.cmake file. Also, inhibit
# auto-detection in a top-level build, because the top-level project file already includes it.
if(NOT QT_BUILD_STANDALONE_TESTS AND NOT QT_SUPER_BUILD)
include(${CMAKE_CURRENT_SOURCE_DIR}/cmake/QtAutoDetect.cmake)
endif()
project(QtBase
VERSION "${QT_REPO_MODULE_VERSION}"
DESCRIPTION "Qt Base Libraries"
HOMEPAGE_URL "https://qt.io/"
LANGUAGES CXX C ASM
)
# Make sure we only use latest private CMake API, aka no compatibility wrappers.
set(QT_NO_INTERNAL_COMPATIBILITY_FUNCTIONS TRUE)
if (CMAKE_CROSSCOMPILING AND CMAKE_SYSROOT)
# When cross compiling with CMake any calls to pkg_check_modules() will
# search into the host system instead of the target sysroot.
# The current work around is based on the discussion found at
# https://gitlab.kitware.com/cmake/cmake/-/merge_requests/4478
set(ENV{PKG_CONFIG_DIR} "")
set(ENV{PKG_CONFIG_LIBDIR} "${CMAKE_SYSROOT}/usr/lib/${CMAKE_LIBRARY_ARCHITECTURE}/pkgconfig")
set(ENV{PKG_CONFIG_SYSROOT_DIR} ${CMAKE_SYSROOT})
endif()
if(NOT QT_BUILD_STANDALONE_TESTS)
## Add some paths to check for cmake modules:
list(PREPEND CMAKE_MODULE_PATH
"${CMAKE_CURRENT_SOURCE_DIR}/cmake"
"${CMAKE_CURRENT_SOURCE_DIR}/cmake/3rdparty/extra-cmake-modules/find-modules"
"${CMAKE_CURRENT_SOURCE_DIR}/cmake/3rdparty/kwin"
)
if(MACOS)
# Add module directory to pick up custom Info.plist template
list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake/macos")
endif()
## Find the build internals package.
set(QT_BUILD_INTERNALS_SKIP_CMAKE_MODULE_PATH_ADDITION TRUE)
list(PREPEND CMAKE_PREFIX_PATH
"${CMAKE_CURRENT_SOURCE_DIR}/cmake"
)
find_package(QtBuildInternals CMAKE_FIND_ROOT_PATH_BOTH)
unset(QT_BUILD_INTERNALS_SKIP_CMAKE_MODULE_PATH_ADDITION)
else()
# When building standalone tests, an istalled BuildInternals package already exists.
find_package(Qt6 REQUIRED COMPONENTS BuildInternals CMAKE_FIND_ROOT_PATH_BOTH)
endif()
qt_build_repo_begin()
if(NOT QT_BUILD_STANDALONE_TESTS)
## Should this Qt be static or dynamically linked?
option(BUILD_SHARED_LIBS "Build Qt statically or dynamically" ON)
set(QT_BUILD_SHARED_LIBS ${BUILD_SHARED_LIBS})
## Should this Qt be built with Werror?
option(WARNINGS_ARE_ERRORS "Build Qt with warnings as errors" ${FEATURE_developer_build})
## QtBase specific configure tests:
include(QtBaseConfigureTests)
## Build System tests:
include(QtBaseCMakeTesting)
## Targets for global features, etc.:
include(QtBaseGlobalTargets)
## Set language standards after QtBaseGlobalTargets, because that's when the relevant
## feature variables are available.
qt_set_language_standards()
#include CoreMacros() for qt6_generate_meta_types()
set(QT_DEFAULT_MAJOR_VERSION 6)
include(src/corelib/Qt6CoreMacros.cmake)
# Needed when building qtbase for android.
include(src/corelib/Qt6AndroidMacros.cmake)
# Set up optimization flags like in qmake.
# This function must be called after the global QT_FEATURE_xxx variables have been set up,
# aka after QtBaseGlobalTargets is processed.
# It also has to be called /before/ adding add_subdirectory(src), so that per-directory
# modifications can still be applied if necessary (like in done in Core and Gui).
qt_internal_set_up_config_optimizations_like_in_qmake()
## Setup documentation
add_subdirectory(doc)
## Visit all the directories:
add_subdirectory(src)
endif()
if(BUILD_TESTING)
add_subdirectory(tests)
if(QT_NO_MAKE_TESTS)
set_property(DIRECTORY tests PROPERTY EXCLUDE_FROM_ALL TRUE)
endif()
endif()
if(NOT QT_BUILD_STANDALONE_TESTS)
if(QT_WILL_BUILD_TOOLS)
add_subdirectory(qmake)
endif()
# As long as we use the mkspecs (for qplatformdefs.h), we need to always
# install it, especially when cross-compiling.
set(mkspecs_install_dir "${INSTALL_MKSPECSDIR}")
qt_path_join(mkspecs_install_dir ${QT_INSTALL_DIR} ${mkspecs_install_dir})
file(GLOB mkspecs_subdirs
LIST_DIRECTORIES TRUE
"${PROJECT_SOURCE_DIR}/mkspecs/*")
foreach(entry IN LISTS mkspecs_subdirs)
if (IS_DIRECTORY ${entry})
qt_copy_or_install(DIRECTORY "${entry}"
DESTINATION ${mkspecs_install_dir}
USE_SOURCE_PERMISSIONS)
else()
qt_copy_or_install(FILES "${entry}"
DESTINATION ${mkspecs_install_dir})
endif()
endforeach()
endif()
qt_build_repo_end()
if(NOT QT_BUILD_STANDALONE_TESTS AND BUILD_EXAMPLES)
add_subdirectory(examples)
if(QT_NO_MAKE_EXAMPLES)
set_property(DIRECTORY examples PROPERTY EXCLUDE_FROM_ALL TRUE)
endif()
endif()