qt5base-lts/cmake/QtModuleDependencies.cmake.in

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# Make sure @INSTALL_CMAKE_NAMESPACE@ is found before anything else.
set(@INSTALL_CMAKE_NAMESPACE@@target@_FOUND FALSE)
CMake: Allow finding Qt CMake packages in additional locations By default, when using the Qt6 CMake package to look for components, the find_package() calls for the components use NO_DEFAULT_PATH to ensure that CMake doesn't accidentally find system (distro) packages. Instead we limit the paths to one level up from where the Qt6 package is. Unfortunately that doesn't quite work for finding Qt packages that might have been installed into a different prefix than where the main Qt prefix is. This happens when Qt addons are built by Conan, and installed into a separate prefix. To allow calls like find_package(Qt6 COMPONENTS ConanAddon) to work in a scenario as described above, introduce a new variable called QT_ADDITIONAL_PACKAGES_PREFIX_PATH which can be used to specify additional paths where Qt CMake packages should be found. This is similar to previously introduced QT_EXAMPLES_CMAKE_PREFIX_PATH variable which was meant for a similar case, but only for examples. Additionally, allow disabling the NO_DEFAULT_PATH option by setting the QT_DISABLE_NO_DEFAULT_PATH_IN_QT_PACKAGES cache variable to TRUE. This would allow regular usage of CMAKE_PREFIX_PATH to work, at the risk that system Qt CMake packages might be found. Augments 5cd4001bf2a7f0894c6ac269860e833b02df6cde and ffe088941378e32ea30c142cca7e63c537a41ff1. Fixes: QTBUG-86882 Change-Id: Ia8e060cbba6d2a10c3d63d81892f2c71e4236a9a Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
2020-09-25 18:02:56 +00:00
if("${_qt_cmake_dir}" STREQUAL "")
set(_qt_cmake_dir "${QT_TOOLCHAIN_RELOCATABLE_CMAKE_DIR}")
endif()
CMake: Allow finding Qt CMake packages in additional locations By default, when using the Qt6 CMake package to look for components, the find_package() calls for the components use NO_DEFAULT_PATH to ensure that CMake doesn't accidentally find system (distro) packages. Instead we limit the paths to one level up from where the Qt6 package is. Unfortunately that doesn't quite work for finding Qt packages that might have been installed into a different prefix than where the main Qt prefix is. This happens when Qt addons are built by Conan, and installed into a separate prefix. To allow calls like find_package(Qt6 COMPONENTS ConanAddon) to work in a scenario as described above, introduce a new variable called QT_ADDITIONAL_PACKAGES_PREFIX_PATH which can be used to specify additional paths where Qt CMake packages should be found. This is similar to previously introduced QT_EXAMPLES_CMAKE_PREFIX_PATH variable which was meant for a similar case, but only for examples. Additionally, allow disabling the NO_DEFAULT_PATH option by setting the QT_DISABLE_NO_DEFAULT_PATH_IN_QT_PACKAGES cache variable to TRUE. This would allow regular usage of CMAKE_PREFIX_PATH to work, at the risk that system Qt CMake packages might be found. Augments 5cd4001bf2a7f0894c6ac269860e833b02df6cde and ffe088941378e32ea30c142cca7e63c537a41ff1. Fixes: QTBUG-86882 Change-Id: Ia8e060cbba6d2a10c3d63d81892f2c71e4236a9a Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io> Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
2020-09-25 18:02:56 +00:00
set(__qt_use_no_default_path_for_qt_packages "NO_DEFAULT_PATH")
if(QT_DISABLE_NO_DEFAULT_PATH_IN_QT_PACKAGES)
set(__qt_use_no_default_path_for_qt_packages "")
endif()
CMake: Record used package version for each target dependency When recording which package version to look for in QtFooModuleDependencies.cmake and other files like it, instead of using PROJECT_VERSION, use the version of the package that contains the dependency. For example if we're hypothetically building the qtdeclarative repo from the 6.4 branch, against an installed 6.2 qtbase, then the Qt6QmlModuleDependencies.cmake file will have a find_package(Qt6Core 6.2) call because qtdeclarative's find_package(Qt6Core) call found a 6.2 Core when it was configured. This allows switching the versioning scheme of specific Qt modules that might not want to follow the general Qt versioning scheme. The first candidate would be QtWebEngine which might want to follow the Chromium versioning scheme, something like Qt 6.94.0 where 94 is the Chromium major version. Implementation notes. We now record the package version of a target in a property called _qt_package_version. We do it for qt modules, plugins, 3rd party libraries, tools and the Platform target. When we try to look up which version to write into the QtFooModuleDependencies.cmake file (or the equivalent Plugins and Tools file), we try to find the version from a few sources: the property mentioned above, then the Qt6{target}_VERSION variable, and finally PROJECT_VERSION. In the latter case, we issue a warning because technically that should never have to happen, and it's a bug or an unforeseen case if it does. A few more places also need adjustments: - package versions to look for when configuring standalone tests and generating standalone tests Config files - handling of tools packages - The main Qt6 package lookup in each Dependencies.cmake files Note that there are some requirements and consequences in case a module wants to use a different versioning scheme like 6.94.0. Requirements. - The root CMakeLists.txt file needs to call find_package with a version different from the usual PROJECT_VERSION. Ideally it should look for a few different Qt versions which are known to be compatible, for example the last stable and LTS versions, or just the lowest supported Qt version, e.g. 6.2.6 or whenever this change would land in the 6.2 branch. - If the repository has multiple modules, some of which need to follow the Qt versioning scheme and some not, project(VERSION x.y.z) calls need to be carefully placed in subdirectory scopes with appropriate version numbers, so that qt_internal_add_module / _tool / _plugin pick up the correct version. Consequences. - The .so / .dylib names will contain the new version, e.g. .so.6.94 - Linux ELF symbols will contain the new versions - syncqt private headers will now exist under a include/QtFoo/6.94.0/QtFoo/private folder - pri and prl files will also contain the new version numbers - pkg-config .pc files contain the new version numbers - It won't be possible to write find_package(Qt6 6.94 COMPONENTS WebEngineWidgets) in user code. One would have to write find_package(Qt6WebEngineWidgets 6.94) otherwise CMake will try to look for Qt6Config 6.94 which won't exist. - Similarly, a find_package(Qt6 6.4 COMPONENTS Widgets WebEngineWidgets) call would always find any kind of WebEngine package that is higher than 6.4, which might be 6.94, 6.95, etc. - In the future, if we fix Qt6Config to pass EXACT to its subcomponent find_package calls, a find_package(Qt6 6.5.0 EXACT COMPONENTS Widgets WebEngineWidgets) would fail to find WebEngineWidgets, because its 6.94.0 version will not be equal to 6.5.0. Currently we don't pass through EXACT, so it's not an issue. Augments 5ffc744b791a114a3180a425dd26e298f7399955 Task-number: QTBUG-103500 Change-Id: I8bdb56bfcbc7f7f6484d1e56651ffc993fd30bab Reviewed-by: Michal Klocek <michal.klocek@qt.io> Reviewed-by: Alexey Edelev <alexey.edelev@qt.io> Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>
2022-05-17 06:44:43 +00:00
# Don't propagate REQUIRED so we don't immediately FATAL_ERROR, rather let the find_dependency calls
# set _NOT_FOUND_MESSAGE which will be displayed by the includer of the Dependencies file.
set(${CMAKE_FIND_PACKAGE_NAME}_FIND_REQUIRED FALSE)
if(NOT @INSTALL_CMAKE_NAMESPACE@_FOUND)
find_dependency(@INSTALL_CMAKE_NAMESPACE@ @main_qt_package_version@
PATHS
${QT_BUILD_CMAKE_PREFIX_PATH}
"${CMAKE_CURRENT_LIST_DIR}/.."
"${_qt_cmake_dir}"
${_qt_additional_packages_prefix_paths}
${__qt_use_no_default_path_for_qt_packages}
)
endif()
# note: _third_party_deps example: "ICU\\;FALSE\\;1.0\\;i18n uc data;ZLIB\\;FALSE\\;\\;"
set(__qt_@target@_third_party_deps "@third_party_deps@")
_qt_internal_find_third_party_dependencies("@target@" __qt_@target@_third_party_deps)
Write find_dependency() calls in Qt Module config files This change introduces a new function called qt_find_package() which can take an extra option called PROVIDED_TARGETS, which associates targets with the package that defines those targets. This is done by setting the INTERFACE_QT_PACKAGE_NAME and INTERFACE_QT_PACKAGE_VERSION properties on the imported targets. This information allows us to generate appropriate find_dependency() calls in a module's Config file for third party libraries. For example when an application links against QtCore, it should also link against zlib and atomic libraries. In order to do that, the library locations first have to be found by CMake. This is achieved by embedding find_dependency(ZLIB) and find_dependency(Atomic) in Qt5CoreDependencies.cmake which is included by Qt5CoreConfig.cmake. The latter is picked up when an application project contains find_package(Qt5Core), and thus all linking dependencies are resolved. The information 'which package provides which targets' is contained in the python json2cmake conversion script. The generated output of the script contains qt_find_package() calls that represent that information. The Qt5CoreDependencies.cmake file and which which dependencies it contains is generated at the QtPostProcess stop. Note that for non-static Qt builds, we only need to propagate public 3rd party libraries. For static builds, we need all third party libraries. In order for the INTERFACE_QT_PACKAGE_NAME property to be read in any scope, the targets on which the property is set, have to be GLOBAL. Also for applications and other modules to find all required third party libraries, we have to install all our custom Find modules, and make sure they define INTERFACE IMPORTED libraries, and not just IMPORTED libraries. Change-Id: I694d6e32d05b96d5e241df0156fc79d0029426aa Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>
2019-04-24 15:14:25 +00:00
# Find Qt tool package.
set(__qt_@target@_tool_deps "@main_module_tool_deps@")
_qt_internal_find_tool_dependencies("@target@" __qt_@target@_tool_deps)
# note: target_deps example: "Qt6Core\;5.12.0;Qt6Gui\;5.12.0"
set(__qt_@target@_target_deps "@target_deps@")
CMake: Fix QT_ADDITIONAL_PACKAGES_PREFIX_PATH for cross-builds The QT_ADDITIONAL_PACKAGES_PREFIX_PATH variable was introduced to allow specifying extra locations to find Qt packages. The reason it was introduced instead of just using CMAKE_PREFIX_PATH is because the Qt6 component find_package call uses NO_DEFAULT_PATH which means CMAKE_PREFIX_PATH is ignored. We use NO_DEFAULT_PATH to ensure we don't accidentally pick up system / distro Qt packages. The paths from QT_ADDITIONAL_PACKAGES_PREFIX_PATH are added to the find_package PATHS option in the Qt6 package, each ModuleDependencies.cmake file and some other places. Unfortunately that's not enough to make it work for cross-builds. Imagine the following scenario. host qtbase, qtdeclarative installed in /host_qt target qtbase installed in /target_qtbase target qtdeclarative installed in /target_qtdeclarative We want to cross-build qtlottie. We configure qtlottie as follows /target_qtbase/bin/qt-configure-module /qtlottie_src -- -DQT_ADDITIONAL_PACKAGES_PREFIX_PATH=/target_qtdeclarative We expect the target QtQuick package to be found, but it won't be. The reason is that QT_ADDITIONAL_PACKAGES_PREFIX_PATH is added to the PATHs option, but we don't adjust CMAKE_FIND_ROOT_PATH. Without adding the new paths in CMAKE_FIND_ROOT_PATH, CMake will re-root the passed PATHs under the existing CMAKE_FIND_ROOT_PATH, which is QT_TOOLCHAIN_RELOCATABLE_INSTALL_PREFIX, which evaluates to /target_qtbase. There is no QtQuick package there. To fix this, prepend the values of QT_ADDITIONAL_PACKAGES_PREFIX_PATH to CMAKE_FIND_ROOT_PATH. The location where we currently do CMAKE_FIND_ROOT_PATH manipulations is in the qt.toolchain.cmake file, so to be consistent, we prepend the new prefixes there as well. We need to adjust both CMAKE_FIND_ROOT_PATH and CMAKE_PREFIX_PATH, due the path re-rooting bug in CMake. See https://gitlab.kitware.com/cmake/cmake/-/issues/21937 as well as the existing comment in qt.toolchain.cmake marked with REROOT_PATH_ISSUE_MARKER. We also need to do a few more things to make the setup work Because Qt6Config uses NO_DEFAULT_PATH, the CMAKE_PREFIX_PATH adjustments we do in the toolchain file are not enough, so we still need to add the same prefixes to the Qt6Config find_package PATHS option. One would ask why do we need to adjust CMAKE_PREFIX_PATH at all then. It's for find_package(Qt6Foo) calls to work which don't go through the Qt6Config umbrella package. To make the CMake re-rooting behavior happy, we need to ensure the provided paths are absolute. So we iterate over the values of QT_ADDITIONAL_PACKAGES_PREFIX_PATH, to make them absolute. We do the same for the environment variable. We need to append lib/cmake to the prefixes which are added to CMAKE_PREFIX_PATH, otherwise the CMake re-rooting bug is hit. We need to specify the Qt6 package location (${_qt_cmake_dir}) to the PATHS option in the various Dependencies.cmake.in files, to ensure that dependency resolution can jump around between the Qt6 dir and the additional prefixes. Previously the dependency lookup code assumed that all dependencies would be within the same prefix. The same is needed for qt and qml plugin dependency lookup. Amends 7bb91398f25cb2016c0558fd397b376f413e3e96 Amends 60c87c68016c6f02b0eddd4002f75a49ab51d4a8 Amends 5bbd700124d13a292ff8bae6045316112500e230 Pick-to: 6.2 Fixes: QTBUG-95854 Change-Id: I35ae82330fec427d0d38fc9a0542ffafff52556a Reviewed-by: Alexey Edelev <alexey.edelev@qt.io> Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-08-17 15:03:02 +00:00
set(__qt_@target@_find_dependency_paths "${CMAKE_CURRENT_LIST_DIR}/.." "${_qt_cmake_dir}")
_qt_internal_find_qt_dependencies("@target@" __qt_@target@_target_deps
__qt_@target@_find_dependency_paths)
set(_@QT_CMAKE_EXPORT_NAMESPACE@@target@_MODULE_DEPENDENCIES "@qt_module_dependencies@")
set(@INSTALL_CMAKE_NAMESPACE@@target@_FOUND TRUE)