diff options
Diffstat (limited to 'cmake/QtCMakeVersionHelpers.cmake')
| -rw-r--r-- | cmake/QtCMakeVersionHelpers.cmake | 162 |
1 files changed, 125 insertions, 37 deletions
diff --git a/cmake/QtCMakeVersionHelpers.cmake b/cmake/QtCMakeVersionHelpers.cmake index 955d9044cb..322e58eed1 100644 --- a/cmake/QtCMakeVersionHelpers.cmake +++ b/cmake/QtCMakeVersionHelpers.cmake @@ -1,29 +1,83 @@ -# Returns the minimum supported CMake version required to build Qt as originally advertised by Qt. -function(qt_internal_get_qt_supported_minimum_cmake_version out_var) - # QT_MIN_SUPPORTED_CMAKE_VERSION is set either in .cmake.conf or in QtBuildInternalsExtras.cmake - # when building a child repo. - set(supported_version "${QT_MIN_SUPPORTED_CMAKE_VERSION}") +# Copyright (C) 2022 The Qt Company Ltd. +# SPDX-License-Identifier: BSD-3-Clause + +# Returns the minimum supported CMake version required to /build/ Qt as originally advertised by Qt. +function(qt_internal_get_supported_min_cmake_version_for_building_qt out_var) + if(NOT DEFINED BUILD_SHARED_LIBS) + message(FATAL_ERROR "BUILD_SHARED_LIBS is needed to decide the minimum CMake version. " + "It should have been set by this point.") + endif() + + # First check if a value is already set in QtBuildInternalsExtras.cmake, which means we're + # building a repo other than qtbase and the minimum version was already recorded. + if(QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT) + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT}") + + # We're building qtbase so the values come from .cmake.conf. + elseif(APPLE) + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT_APPLE}") + elseif(BUILD_SHARED_LIBS) + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT_SHARED}") + else() + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT_STATIC}") + endif() + set(${out_var} "${supported_version}" PARENT_SCOPE) endfunction() -# Returns the computed minimum supported CMake version required to build Qt. -function(qt_internal_get_computed_minimum_cmake_version out_var) - qt_internal_get_qt_supported_minimum_cmake_version(min_supported_version) - set(computed_min_version "${min_supported_version}") +# Returns the minimum supported CMake version required to /use/ Qt as originally advertised by Qt. +function(qt_internal_get_supported_min_cmake_version_for_using_qt out_var) + if(NOT DEFINED BUILD_SHARED_LIBS) + message(FATAL_ERROR "BUILD_SHARED_LIBS is needed to decide the minimum CMake version. " + "It should have been set by this point.") + endif() - # Set in QtBuildInternalsExtras.cmake. - if(QT_COMPUTED_MIN_CMAKE_VERSION) - set(computed_min_version "${QT_COMPUTED_MIN_CMAKE_VERSION}") + if(APPLE) + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_USING_QT_APPLE}") + elseif(BUILD_SHARED_LIBS) + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_USING_QT_SHARED}") + else() + set(supported_version "${QT_SUPPORTED_MIN_CMAKE_VERSION_FOR_USING_QT_STATIC}") endif() + set(${out_var} "${supported_version}" PARENT_SCOPE) +endfunction() + +# Returns the computed minimum supported CMake version required to /build/ Qt. +function(qt_internal_get_computed_min_cmake_version_for_building_qt out_var) # An explicit override for those that take it upon themselves to fix the build system # when using a CMake version lower than the one officially supported. # Also useful for build testing locally with different minimum versions to observe different # policy behaviors. - if(QT_FORCE_MIN_CMAKE_VERSION) - set(computed_min_version "${QT_FORCE_MIN_CMAKE_VERSION}") + if(QT_FORCE_MIN_CMAKE_VERSION_FOR_BUILDING_QT) + set(computed_min_version "${QT_FORCE_MIN_CMAKE_VERSION_FOR_BUILDING_QT}") + + # Set in QtBuildInternalsExtras.cmake, which means it was already computed as part of qtbase + # configuration. + elseif(QT_COMPUTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT) + set(computed_min_version "${QT_COMPUTED_MIN_CMAKE_VERSION_FOR_BUILDING_QT}") + + # No override was given and the version was not computed before, thus initialize with the + # default minimum. + else() + qt_internal_get_supported_min_cmake_version_for_building_qt(min_supported_version) + set(computed_min_version "${min_supported_version}") endif() + set(${out_var} "${computed_min_version}" PARENT_SCOPE) +endfunction() +# Returns the computed minimum supported CMake version required to /use/ Qt. +function(qt_internal_get_computed_min_cmake_version_for_using_qt out_var) + # Allow overriding the required minimum CMake version for user projects, without forcing + # each project developer to have to override it manually. + if(QT_FORCE_MIN_CMAKE_VERSION_FOR_USING_QT) + set(computed_min_version "${QT_FORCE_MIN_CMAKE_VERSION_FOR_USING_QT}") + + # No override was given, thus initialize with the default minimum. + else() + qt_internal_get_supported_min_cmake_version_for_using_qt(min_supported_version) + set(computed_min_version "${min_supported_version}") + endif() set(${out_var} "${computed_min_version}" PARENT_SCOPE) endfunction() @@ -52,46 +106,54 @@ function(qt_internal_get_max_new_policy_cmake_version out_var) set(${out_var} "${upper_version}" PARENT_SCOPE) endfunction() -function(qt_internal_check_for_suitable_cmake_version) - # Implementation note. - # The very first cmake_minimum_required() call can't be placed in an include()d file. - # It causes CMake to fail to configure with 'No cmake_minimum_required command is present.' - # The first cmake_minimum_required() must be called directly in the top-level CMakeLists.txt - # file. - # That's why this function only handles output of warnings, and doesn't try to set the required - # version. - qt_internal_check_minimum_cmake_version() - qt_internal_warn_about_unsuitable_cmake_versions() +function(qt_internal_check_and_warn_about_unsuitable_cmake_version) + # Don't show the warnings multiple times in a top-level build. + get_cmake_property(check_done _qt_unsuitable_cmake_version_check_done) + if(check_done) + return() + endif() + set_property(GLOBAL PROPERTY _qt_unsuitable_cmake_version_check_done TRUE) + + qt_internal_warn_if_min_cmake_version_not_met() + qt_internal_warn_about_buggy_cmake_versions() endfunction() -# Function to be used in child repos like qtsvg to require a minimum CMake version. +# Function to be used in downstream repos (like qtsvg) to require a minimum CMake version and warn +# about unsuitable cmake versions. # # Such repos don't have the required version information at cmake_minimum_required() time, that's # why we provide this function to be called at a time when the info is available. function(qt_internal_require_suitable_cmake_version) - qt_internal_check_for_suitable_cmake_version() - qt_internal_get_computed_minimum_cmake_version(computed_min_version) + qt_internal_check_and_warn_about_unsuitable_cmake_version() + qt_internal_get_computed_min_cmake_version_for_building_qt(computed_min_version) if(CMAKE_VERSION VERSION_LESS computed_min_version) - message(FATAL_ERROR "CMake ${computed_min_version} or higher is required. " - "You are running version ${CMAKE_VERSION}") + set(major_minor "${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}") + message(FATAL_ERROR + "CMake ${computed_min_version} or higher is required. " + "You are running version ${CMAKE_VERSION} " + "\nQt requires newer CMake features to build correctly. You can lower the minimum " + "required version by passing " + "-DQT_FORCE_MIN_CMAKE_VERSION_FOR_BUILDING_QT=${major_minor} when configuring Qt. " + "Building Qt with this CMake version is not officially supported. Use at your own risk." + ) endif() endfunction() -function(qt_internal_check_minimum_cmake_version) - qt_internal_get_qt_supported_minimum_cmake_version(min_supported_version) - qt_internal_get_computed_minimum_cmake_version(computed_min_version) +function(qt_internal_warn_if_min_cmake_version_not_met) + qt_internal_get_supported_min_cmake_version_for_building_qt(min_supported_version) + qt_internal_get_computed_min_cmake_version_for_building_qt(computed_min_version) if(NOT min_supported_version STREQUAL computed_min_version AND computed_min_version VERSION_LESS min_supported_version) message(WARNING - "The minimum required CMake version to build Qt is '${min_supported_version}'. " - "You have explicitly chosen to require a lower minimum CMake version, namely '${computed_min_version}'. " - "Building Qt with such a CMake version is not officially supported. Use at your own risk.") + "The minimum required CMake version to build Qt is: '${min_supported_version}'. " + "You have explicitly chosen to require a lower minimum CMake version: '${computed_min_version}'. " + "Building Qt with this CMake version is not officially supported. Use at your own risk.") endif() endfunction() -function(qt_internal_warn_about_unsuitable_cmake_versions) +function(qt_internal_warn_about_buggy_cmake_versions) set(unsuitable_versions "") # Touching a library's source file causes unnecessary rebuilding of unrelated targets. @@ -116,6 +178,30 @@ function(qt_internal_warn_about_unsuitable_cmake_versions) # https://gitlab.kitware.com/cmake/cmake/-/issues/21163 list(APPEND unsuitable_versions "3.18.2") + # Cyclic dependencies are created when mixing AUTOMOC/AUTOUIC with sources + # that have their SKIP_MOC or SKIP_UIC source file properties set to true. + # https://gitlab.kitware.com/cmake/cmake/-/issues/21977 + list(APPEND unsuitable_versions "3.20.0") + + # AUTOMOC can crash or hang when using a Qt that supports moc depfiles. + # Issues reported on Windows with Ninja and Makefiles, but it could be happening + # on other platforms too. + # https://gitlab.kitware.com/cmake/cmake/-/issues/22014 + list(APPEND unsuitable_versions "3.20.1") + + # Cyclic dependencies can happen when the AUTOMOC / AUTOUIC include directory is added as a + # target include directory. + # https://gitlab.kitware.com/cmake/cmake/-/merge_requests/6380 + # https://gitlab.kitware.com/cmake/cmake/-/merge_requests/6359 + # https://gitlab.kitware.com/cmake/cmake/-/issues/16776 + list(APPEND unsuitable_versions "3.21.0") + + # Changing a C++ source file can trigger rebuilds of a lot of other source files that might + # include AUTOGEN'ed headers or sources. + # https://gitlab.kitware.com/cmake/cmake/-/issues/22531 + # Fixed in 3.21.2. + list(APPEND unsuitable_versions "3.21.1") + foreach(unsuitable_version ${unsuitable_versions}) if(CMAKE_VERSION VERSION_EQUAL unsuitable_version) message(WARNING @@ -136,13 +222,15 @@ function(qt_internal_warn_about_unsuitable_cmake_versions) endif() endfunction() +# Used to upgrade policies only when building Qt repositories. +# # Functions don't have their own policy scope, so the policy settings modified # here will be those of the caller's policy scope. Note that these settings # will only apply to functions and macros defined after this function is called, # but not to any that are already defined. Ordinary CMake code not inside a # function or macro will be affected by these policy settings too. function(qt_internal_upgrade_cmake_policies) - qt_internal_get_computed_minimum_cmake_version(lower_version) + qt_internal_get_computed_min_cmake_version_for_building_qt(lower_version) qt_internal_get_max_new_policy_cmake_version(upper_version) cmake_minimum_required(VERSION ${lower_version}...${upper_version}) endfunction() |