qt5base-lts/cmake/QtFindPackageHelpers.cmake
Alexandru Croitor dd1030a450 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 5ffc744b79

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>
2022-07-01 10:50:57 +02:00

452 lines
21 KiB
CMake

# This function recursively walks transitive link libraries of the given target
# and promotes those targets to be IMPORTED_GLOBAL if they are not.
#
# This is required for .prl file generation in top-level builds, to make sure that imported 3rd
# party library targets in any repo are made global, so there are no scoping issues.
#
# Only works if called from qt_find_package(), because the promotion needs to happen in the same
# directory scope where the imported target is first created.
#
# Uses __qt_internal_walk_libs.
function(qt_find_package_promote_targets_to_global_scope target)
__qt_internal_walk_libs("${target}" _discarded_out_var _discarded_out_var_2
"qt_find_package_targets_dict" "promote_global")
endfunction()
macro(qt_find_package)
# Get the target names we expect to be provided by the package.
set(find_package_options CONFIG NO_MODULE MODULE REQUIRED)
set(options ${find_package_options} MARK_OPTIONAL)
set(oneValueArgs MODULE_NAME QMAKE_LIB)
set(multiValueArgs PROVIDED_TARGETS COMPONENTS OPTIONAL_COMPONENTS)
cmake_parse_arguments(arg "${options}" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
# If some Qt internal project calls qt_find_package(WrapFreeType), but WrapFreeType was already
# found as part of a find_dependency() call from a ModuleDependencies.cmake file (or similar),
# and the provided target is also found, that means this might have been an unnecessary
# qt_find_package() call, because the dependency was already found via some other transitive
# dependency. Return early, so that CMake doesn't fail with an error with trying to promote the
# targets to be global. This behavior is not enabled by default, because there are cases
# when a regular find_package() (non qt_) can find a package (Freetype -> PNG), and a subsequent
# qt_find_package(PNG PROVIDED_TARGET PNG::PNG) still needs to succeed and register the provided
# targets. To enable the debugging behavior, set QT_DEBUG_QT_FIND_PACKAGE to 1.
set(_qt_find_package_skip_find_package FALSE)
if(QT_DEBUG_QT_FIND_PACKAGE AND ${ARGV0}_FOUND AND arg_PROVIDED_TARGETS)
set(_qt_find_package_skip_find_package TRUE)
foreach(qt_find_package_target_name ${arg_PROVIDED_TARGETS})
if(NOT TARGET ${qt_find_package_target_name})
set(_qt_find_package_skip_find_package FALSE)
endif()
endforeach()
if(_qt_find_package_skip_find_package)
message(AUTHOR_WARNING "qt_find_package(${ARGV0}) called even though the package "
"was already found. Consider removing the call.")
endif()
endif()
# When configure.cmake is included only to record summary entries, there's no point in looking
# for the packages.
if(__QtFeature_only_record_summary_entries)
set(_qt_find_package_skip_find_package TRUE)
endif()
# Get the version if specified.
set(package_version "")
if(${ARGC} GREATER_EQUAL 2)
if(${ARGV1} MATCHES "^[0-9\.]+$")
set(package_version "${ARGV1}")
endif()
endif()
if(arg_COMPONENTS)
# Re-append components to forward them.
list(APPEND arg_UNPARSED_ARGUMENTS "COMPONENTS;${arg_COMPONENTS}")
endif()
if(arg_OPTIONAL_COMPONENTS)
# Re-append optional components to forward them.
list(APPEND arg_UNPARSED_ARGUMENTS "OPTIONAL_COMPONENTS;${arg_OPTIONAL_COMPONENTS}")
endif()
# Don't look for packages in PATH if requested to.
if(QT_NO_USE_FIND_PACKAGE_SYSTEM_ENVIRONMENT_PATH)
set(_qt_find_package_use_system_env_backup "${CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH}")
set(CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH "OFF")
endif()
if(NOT (arg_CONFIG OR arg_NO_MODULE OR arg_MODULE) AND NOT _qt_find_package_skip_find_package)
# Try to find a config package first in quiet mode
set(config_package_arg ${arg_UNPARSED_ARGUMENTS})
list(APPEND config_package_arg "CONFIG;QUIET")
find_package(${config_package_arg})
# Double check that in config mode the targets become visible. Sometimes
# only the module mode creates the targets. For example with vcpkg, the sqlite
# package provides sqlite3-config.cmake, which offers multi-config targets but
# in their own way. CMake has FindSQLite3.cmake and with the original
# qt_find_package(SQLite3) call it is our intention to use the cmake package
# in module mode.
unset(_qt_any_target_found)
unset(_qt_should_unset_found_var)
if(${ARGV0}_FOUND AND arg_PROVIDED_TARGETS)
foreach(expected_target ${arg_PROVIDED_TARGETS})
if (TARGET ${expected_target})
set(_qt_any_target_found TRUE)
break()
endif()
endforeach()
if(NOT _qt_any_target_found)
set(_qt_should_unset_found_var TRUE)
endif()
endif()
# If we consider the package not to be found, make sure to unset both regular
# and CACHE vars, otherwise CMP0126 set to NEW might cause issues with
# packages not being found correctly.
if(NOT ${ARGV0}_FOUND OR _qt_should_unset_found_var)
unset(${ARGV0}_FOUND)
unset(${ARGV0}_FOUND CACHE)
# Unset the NOTFOUND ${package}_DIR var that might have been set by the previous
# find_package call, to get rid of "not found" messages in the feature summary
# if the package is found by the next find_package call.
if(DEFINED CACHE{${ARGV0}_DIR} AND NOT ${ARGV0}_DIR)
unset(${ARGV0}_DIR CACHE)
endif()
endif()
endif()
# Ensure the options are back in the original unparsed arguments
foreach(opt IN LISTS find_package_options)
if(arg_${opt})
list(APPEND arg_UNPARSED_ARGUMENTS ${opt})
endif()
endforeach()
# TODO: Handle packages with components where a previous component is already found.
# E.g. find_package(Qt6 COMPONENTS BuildInternals) followed by
# qt_find_package(Qt6 COMPONENTS Core) doesn't end up calling find_package(Qt6Core).
if (NOT ${ARGV0}_FOUND AND NOT _qt_find_package_skip_find_package)
# Call original function without our custom arguments.
find_package(${arg_UNPARSED_ARGUMENTS})
endif()
if(QT_NO_USE_FIND_PACKAGE_SYSTEM_ENVIRONMENT_PATH)
if("${_qt_find_package_use_system_env_backup}" STREQUAL "")
unset(CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH)
else()
set(CMAKE_FIND_USE_SYSTEM_ENVIRONMENT_PATH "${_qt_find_package_use_system_env_backup}")
endif()
endif()
if(${ARGV0}_FOUND AND arg_PROVIDED_TARGETS AND NOT _qt_find_package_skip_find_package)
# If package was found, associate each target with its package name. This will be used
# later when creating Config files for Qt libraries, to generate correct find_dependency()
# calls. Also make the provided targets global, so that the properties can be read in
# all scopes.
foreach(qt_find_package_target_name ${arg_PROVIDED_TARGETS})
if(TARGET ${qt_find_package_target_name})
# Allow usage of aliased targets by setting properties on the actual target
get_target_property(aliased_target ${qt_find_package_target_name} ALIASED_TARGET)
if(aliased_target)
set(qt_find_package_target_name ${aliased_target})
endif()
set_target_properties(${qt_find_package_target_name} PROPERTIES
INTERFACE_QT_PACKAGE_NAME ${ARGV0}
INTERFACE_QT_PACKAGE_IS_OPTIONAL ${arg_MARK_OPTIONAL})
if(package_version)
set_target_properties(${qt_find_package_target_name}
PROPERTIES INTERFACE_QT_PACKAGE_VERSION ${ARGV1})
endif()
if(arg_COMPONENTS)
string(REPLACE ";" " " components_as_string "${arg_COMPONENTS}")
set_property(TARGET ${qt_find_package_target_name}
PROPERTY INTERFACE_QT_PACKAGE_COMPONENTS ${components_as_string})
endif()
if(arg_OPTIONAL_COMPONENTS)
string(REPLACE ";" " " components_as_string "${arg_OPTIONAL_COMPONENTS}")
set_property(TARGET ${qt_find_package_target_name}
PROPERTY INTERFACE_QT_PACKAGE_OPTIONAL_COMPONENTS
${components_as_string})
endif()
get_property(is_global TARGET ${qt_find_package_target_name} PROPERTY
IMPORTED_GLOBAL)
qt_internal_should_not_promote_package_target_to_global(
"${qt_find_package_target_name}" should_not_promote)
if(NOT is_global AND NOT should_not_promote)
__qt_internal_promote_target_to_global(${qt_find_package_target_name})
qt_find_package_promote_targets_to_global_scope(
"${qt_find_package_target_name}")
endif()
endif()
endforeach()
if(arg_MODULE_NAME AND arg_QMAKE_LIB
AND (NOT arg_QMAKE_LIB IN_LIST QT_QMAKE_LIBS_FOR_${arg_MODULE_NAME}))
set(QT_QMAKE_LIBS_FOR_${arg_MODULE_NAME}
${QT_QMAKE_LIBS_FOR_${arg_MODULE_NAME}};${arg_QMAKE_LIB} CACHE INTERNAL "")
set(QT_TARGETS_OF_QMAKE_LIB_${arg_QMAKE_LIB} ${arg_PROVIDED_TARGETS} CACHE INTERNAL "")
foreach(provided_target ${arg_PROVIDED_TARGETS})
set(QT_QMAKE_LIB_OF_TARGET_${provided_target} ${arg_QMAKE_LIB} CACHE INTERNAL "")
endforeach()
endif()
endif()
endmacro()
# Return qmake library name for the given target, e.g. return "vulkan" for "Vulkan::Vulkan".
function(qt_internal_map_target_to_qmake_lib target out_var)
set(${out_var} "${QT_QMAKE_LIB_OF_TARGET_${target}}" PARENT_SCOPE)
endfunction()
# This function records a dependency between ${main_target_name} and ${dep_package_name}.
# at the CMake package level.
# E.g. The Tools package that provides the qtwaylandscanner target
# needs to call find_package(WaylandScanner) (non-qt-package).
# main_target_name = qtwaylandscanner
# dep_package_name = WaylandScanner
function(qt_record_extra_package_dependency main_target_name dep_package_name dep_package_version)
if(NOT TARGET "${main_target_name}")
qt_get_tool_target_name(main_target_name "${main_target_name}")
endif()
if (TARGET "${main_target_name}")
get_target_property(extra_packages "${main_target_name}" QT_EXTRA_PACKAGE_DEPENDENCIES)
if(NOT extra_packages)
set(extra_packages "")
endif()
list(APPEND extra_packages "${dep_package_name}\;${dep_package_version}")
set_target_properties("${main_target_name}" PROPERTIES QT_EXTRA_PACKAGE_DEPENDENCIES
"${extra_packages}")
endif()
endfunction()
# This function records a dependency between ${main_target_name} and ${dep_target_name}
# at the CMake package level.
# E.g. Qt6CoreConfig.cmake needs to find_package(Qt6EntryPointPrivate).
# main_target_name = Core
# dep_target_name = EntryPointPrivate
# This is just a convenience function that deals with Qt targets and their associated packages
# instead of raw package names.
function(qt_record_extra_qt_package_dependency main_target_name dep_target_name
dep_package_version)
# EntryPointPrivate -> Qt6EntryPointPrivate.
qt_internal_qtfy_target(qtfied_target_name "${dep_target_name}")
qt_record_extra_package_dependency("${main_target_name}"
"${qtfied_target_name_versioned}" "${dep_package_version}")
endfunction()
# This function records a 'QtFooTools' package dependency for the ${main_target_name} target
# onto the ${dep_package_name} tools package.
# E.g. The QtWaylandCompositor package needs to call find_package(QtWaylandScannerTools).
# main_target_name = WaylandCompositor
# dep_package_name = Qt6WaylandScannerTools
function(qt_record_extra_main_tools_package_dependency
main_target_name dep_package_name dep_package_version)
if(NOT TARGET "${main_target_name}")
qt_get_tool_target_name(main_target_name "${main_target_name}")
endif()
if (TARGET "${main_target_name}")
get_target_property(extra_packages "${main_target_name}"
QT_EXTRA_TOOLS_PACKAGE_DEPENDENCIES)
if(NOT extra_packages)
set(extra_packages "")
endif()
list(APPEND extra_packages "${dep_package_name}\;${dep_package_version}")
set_target_properties("${main_target_name}" PROPERTIES QT_EXTRA_TOOLS_PACKAGE_DEPENDENCIES
"${extra_packages}")
endif()
endfunction()
# This function records a 'QtFooTools' package dependency for the ${main_target_name} target
# onto the ${dep_non_versioned_package_name} Tools package.
# main_target_name = WaylandCompositor
# dep_non_versioned_package_name = WaylandScannerTools
# This is just a convenience function to avoid hardcoding the qtified version in the dep package
# name.
function(qt_record_extra_qt_main_tools_package_dependency main_target_name
dep_non_versioned_package_name
dep_package_version)
# WaylandScannerTools -> Qt6WaylandScannerTools.
qt_internal_qtfy_target(qtfied_package_name "${dep_non_versioned_package_name}")
qt_record_extra_main_tools_package_dependency(
"${main_target_name}" "${qtfied_package_name_versioned}" "${dep_package_version}")
endfunction()
# Record an extra 3rd party target as a dependency for ${main_target_name}.
#
# Adds a find_package(${dep_target_package_name}) in ${main_target_name}Dependencies.cmake.
#
# Needed to record a dependency on the package that provides WrapVulkanHeaders::WrapVulkanHeaders.
# The package version, components, whether the package is optional, etc, are queried from the
# ${dep_target} target properties.
function(qt_record_extra_third_party_dependency main_target_name dep_target)
if(NOT TARGET "${main_target_name}")
qt_get_tool_target_name(main_target_name "${main_target_name}")
endif()
if(TARGET "${main_target_name}")
get_target_property(extra_deps "${main_target_name}" _qt_extra_third_party_dep_targets)
if(NOT extra_deps)
set(extra_deps "")
endif()
list(APPEND extra_deps "${dep_target}")
set_target_properties("${main_target_name}" PROPERTIES _qt_extra_third_party_dep_targets
"${extra_deps}")
endif()
endfunction()
# Sets out_var to TRUE if the non-namespaced ${lib} target is exported as part of Qt6Targets.cmake.
function(qt_internal_is_lib_part_of_qt6_package lib out_var)
if (lib STREQUAL "Platform"
OR lib STREQUAL "GlobalConfig"
OR lib STREQUAL "GlobalConfigPrivate"
OR lib STREQUAL "PlatformModuleInternal"
OR lib STREQUAL "PlatformPluginInternal"
OR lib STREQUAL "PlatformToolInternal")
set(${out_var} "TRUE" PARENT_SCOPE)
else()
set(${out_var} "FALSE" PARENT_SCOPE)
endif()
endfunction()
# Try to get the CMake package version of a Qt target.
#
# Query the target's _qt_package_version property, or try to read it from the CMake package version
# variable set from calling find_package(Qt6${target}).
# Not all targets will have a find_package _VERSION variable, for example if the target is an
# executable.
# A heuristic is used to handle QtFooPrivate module targets.
# If no version can be found, fall back to ${PROJECT_VERSION} and issue a warning.
function(qt_internal_get_package_version_of_target target package_version_out_var)
qt_internal_is_lib_part_of_qt6_package("${target}" is_part_of_qt6)
if(is_part_of_qt6)
# When building qtbase, Qt6_VERSION is not set (unless examples are built in-tree,
# non-ExternalProject). Use the Platform target's version instead which would be the
# equivalent.
if(TARGET "${QT_CMAKE_EXPORT_NAMESPACE}::Platform")
get_target_property(package_version
"${QT_CMAKE_EXPORT_NAMESPACE}::Platform" _qt_package_version)
endif()
if(NOT package_version)
set(package_version "${${QT_CMAKE_EXPORT_NAMESPACE}_VERSION}")
endif()
else()
# Try to get the version from the target.
# Try the Private target first and if it doesn't exist, try the non-Private target later.
if(TARGET "${QT_CMAKE_EXPORT_NAMESPACE}::${target}")
get_target_property(package_version
"${QT_CMAKE_EXPORT_NAMESPACE}::${target}" _qt_package_version)
endif()
# Try to get the version from the corresponding package version variable.
if(NOT package_version)
set(package_version "${${QT_CMAKE_EXPORT_NAMESPACE}${target}_VERSION}")
endif()
# Try non-Private target.
if(NOT package_version AND target MATCHES "(.*)Private$")
set(target "${CMAKE_MATCH_1}")
endif()
if(NOT package_version AND TARGET "${QT_CMAKE_EXPORT_NAMESPACE}::${target}")
get_target_property(package_version
"${QT_CMAKE_EXPORT_NAMESPACE}::${target}" _qt_package_version)
endif()
if(NOT package_version)
set(package_version "${${QT_CMAKE_EXPORT_NAMESPACE}${target}_VERSION}")
endif()
endif()
if(NOT package_version)
set(package_version "${PROJECT_VERSION}")
if(FEATURE_developer_build)
message(WARNING
"Could not determine package version of target ${target}. "
"Defaulting to project version ${PROJECT_VERSION}.")
endif()
endif()
set(${package_version_out_var} "${package_version}" PARENT_SCOPE)
endfunction()
# This function stores the list of Qt targets a library depend on,
# along with their version info, for usage in ${target}Depends.cmake file
function(qt_register_target_dependencies target public_libs private_libs)
get_target_property(target_deps "${target}" _qt_target_deps)
if(NOT target_deps)
set(target_deps "")
endif()
get_target_property(target_type ${target} TYPE)
set(lib_list ${public_libs})
set(target_is_shared FALSE)
set(target_is_static FALSE)
if(target_type STREQUAL "SHARED_LIBRARY")
set(target_is_shared TRUE)
elseif(target_type STREQUAL "STATIC_LIBRARY")
set(target_is_static TRUE)
endif()
# Record 'Qt::Foo'-like private dependencies of static library targets, this will be used to
# generate find_dependency() calls.
#
# Private static library dependencies will become $<LINK_ONLY:> dependencies in
# INTERFACE_LINK_LIBRARIES.
if(target_is_static)
list(APPEND lib_list ${private_libs})
endif()
foreach(lib IN LISTS lib_list)
if ("${lib}" MATCHES "^Qt::(.*)")
set(lib "${CMAKE_MATCH_1}")
qt_internal_is_lib_part_of_qt6_package("${lib}" is_part_of_qt6)
qt_internal_get_package_version_of_target("${lib}" package_version)
if (is_part_of_qt6)
list(APPEND target_deps "Qt6\;${package_version}")
else()
list(APPEND target_deps "${INSTALL_CMAKE_NAMESPACE}${lib}\;${package_version}")
endif()
endif()
endforeach()
# Record 'Qt::Foo'-like shared private dependencies of shared library targets.
#
# Private shared library dependencies are listed in the target's
# IMPORTED_LINK_DEPENDENT_LIBRARIES and used in rpath-link calculation.
# See QTBUG-86533 for some details.
# We filter out static libraries and common platform targets, but include both SHARED and
# INTERFACE libraries. INTERFACE libraries in most cases will be FooPrivate libraries.
if(target_is_shared AND private_libs)
foreach(lib IN LISTS private_libs)
if ("${lib}" MATCHES "^Qt::(.*)")
set(lib_namespaced "${lib}")
set(lib "${CMAKE_MATCH_1}")
qt_internal_is_lib_part_of_qt6_package("${lib}" is_part_of_qt6)
get_target_property(lib_type "${lib_namespaced}" TYPE)
if(NOT lib_type STREQUAL "STATIC_LIBRARY" AND NOT is_part_of_qt6)
qt_internal_get_package_version_of_target("${lib}" package_version)
list(APPEND target_deps "${INSTALL_CMAKE_NAMESPACE}${lib}\;${package_version}")
endif()
endif()
endforeach()
endif()
set_target_properties("${target}" PROPERTIES _qt_target_deps "${target_deps}")
endfunction()
# Sets out_var to to TRUE if the target was marked to not be promoted to global scope.
function(qt_internal_should_not_promote_package_target_to_global target out_var)
get_property(should_not_promote TARGET "${target}" PROPERTY _qt_no_promote_global)
set("${out_var}" "${should_not_promote}" PARENT_SCOPE)
endfunction()