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Diffstat (limited to 'cmake/QtPublicWalkLibsHelpers.cmake')
| -rw-r--r-- | cmake/QtPublicWalkLibsHelpers.cmake | 334 |
1 files changed, 334 insertions, 0 deletions
diff --git a/cmake/QtPublicWalkLibsHelpers.cmake b/cmake/QtPublicWalkLibsHelpers.cmake new file mode 100644 index 0000000000..f79b70c710 --- /dev/null +++ b/cmake/QtPublicWalkLibsHelpers.cmake @@ -0,0 +1,334 @@ +# Copyright (C) 2022 The Qt Company Ltd. +# SPDX-License-Identifier: BSD-3-Clause + +# Add libraries to variable ${out_libs_var} in a way that duplicates +# are added at the end. This ensures the library order needed for the +# linker. +function(__qt_internal_merge_libs out_libs_var) + foreach(dep ${ARGN}) + list(REMOVE_ITEM ${out_libs_var} ${dep}) + list(APPEND ${out_libs_var} ${dep}) + endforeach() + set(${out_libs_var} ${${out_libs_var}} PARENT_SCOPE) +endfunction() + + +# Extracts value from per-target dict key and assigns it to out_var. +# Assumes dict_name to be an existing INTERFACE target. +function(__qt_internal_get_dict_key_values out_var target_infix dict_name dict_key) + get_target_property(values "${dict_name}" "INTERFACE_${target_infix}_${dict_key}") + set(${out_var} "${values}" PARENT_SCOPE) +endfunction() + + +# Assigns 'values' to per-target dict key, including for aliases of the target. +# Assumes dict_name to be an existing INTERFACE target. +function(__qt_internal_memoize_values_in_dict target dict_name dict_key values) + # Memoize the computed values for the target as well as its aliases. + # + # Aka assigns the contents of ${values} to INTERFACE_Core, INTERFACE_Qt::Core, + # INTERFACE_Qt6::Core. + # + # Yes, i know it's crazy that target names are legal property names. + # + # Assigning for library aliases is needed to avoid multiple recomputation of values. + # Scenario in the context of __qt_internal_walk_libs: + # 'values' are computed for Core target and memoized to INTERFACE_Core. + # When processing Gui, it depends on Qt::Core, but there are no values for INTERFACE_Qt::Core. + set_target_properties(${dict_name} PROPERTIES INTERFACE_${target}_${dict_key} "${values}") + + get_target_property(versionless_alias "${target}" "_qt_versionless_alias") + if(versionless_alias) + __qt_internal_get_dict_key_values( + versionless_values "${versionless_alias}" "${dict_name}" "${dict_key}") + if(versionless_values MATCHES "-NOTFOUND$") + set_target_properties(${dict_name} + PROPERTIES INTERFACE_${versionless_alias}_${dict_key} "${values}") + endif() + endif() + + get_target_property(versionfull_alias "${target}" "_qt_versionfull_alias") + if(versionfull_alias) + __qt_internal_get_dict_key_values( + versionfull_values "${versionfull_alias}" "${dict_name}" "${dict_key}") + if(versionfull_values MATCHES "-NOTFOUND$") + set_target_properties(${dict_name} + PROPERTIES INTERFACE_${versionfull_alias}_${dict_key} "${values}") + endif() + endif() +endfunction() + + +# Walks a target's public link libraries recursively, and performs some actions (poor man's +# polypmorphism) +# +# Walks INTERFACE_LINK_LIBRARIES for all target types, as well as LINK_LIBRARIES for static +# library targets. +# +# out_var: the name of the variable where the result will be assigned. The result is a list of +# libraries, mostly in generator expression form. +# rcc_objects_out_var: the name of the variable where the collected rcc object files will be +# assigned (for the initial target and its dependencies) +# dict_name: used for caching the results, and preventing the same target from being processed +# twice +# operation: a string to tell the function what additional behaviors to execute. +# 'collect_libs' (default) operation is to collect linker file paths and flags. +# Used for prl file generation. +# 'promote_global' promotes walked imported targets to global scope. +# 'collect_targets' collects all target names (discards framework or link flags) +# 'direct_targets' collects only the direct target names (discards framework or link +# flags) +# +# +function(__qt_internal_walk_libs + target out_var rcc_objects_out_var dict_name operation) + set(collected ${ARGN}) + if(target IN_LIST collected) + return() + endif() + list(APPEND collected ${target}) + + if(operation MATCHES "^direct") + set(direct TRUE) + else() + set(direct FALSE) + endif() + + if(target STREQUAL "${QT_CMAKE_EXPORT_NAMESPACE}::EntryPointPrivate") + # We can't (and don't need to) process EntryPointPrivate because it brings in + # $<TARGET_PROPERTY:prop> genexes which get replaced with + # $<TARGET_PROPERTY:EntryPointPrivate,prop> genexes in the code below and that causes + # 'INTERFACE_LIBRARY targets may only have whitelisted properties.' errors with CMake + # versions equal to or lower than 3.18. These errors are super unintuitive to debug + # because there's no mention that it's happening during a file(GENERATE) call. + return() + endif() + + if(NOT TARGET ${dict_name}) + add_library(${dict_name} INTERFACE IMPORTED GLOBAL) + endif() + __qt_internal_get_dict_key_values(libs "${target}" "${dict_name}" "libs") + __qt_internal_get_dict_key_values(rcc_objects "${target}" "${dict_name}" "rcc_objects") + + if(libs MATCHES "-NOTFOUND$") + unset(libs) + unset(rcc_objects) + get_target_property(target_libs ${target} INTERFACE_LINK_LIBRARIES) + if(NOT target_libs) + unset(target_libs) + endif() + get_target_property(target_type ${target} TYPE) + if(target_type STREQUAL "STATIC_LIBRARY") + get_target_property(link_libs ${target} LINK_LIBRARIES) + if(link_libs) + list(APPEND target_libs ${link_libs}) + endif() + endif() + + # Need to record the rcc object file info not only for dependencies, but also for + # the current target too. Otherwise the saved information is incomplete for prl static + # build purposes. + get_target_property(main_target_rcc_objects ${target} _qt_rcc_objects) + if(main_target_rcc_objects) + __qt_internal_merge_libs(rcc_objects ${main_target_rcc_objects}) + endif() + + foreach(lib ${target_libs}) + # Cannot use $<TARGET_POLICY:...> in add_custom_command. + # Check the policy now, and replace the generator expression with the value. + while(lib MATCHES "\\$<TARGET_POLICY:([^>]+)>") + cmake_policy(GET ${CMAKE_MATCH_1} value) + if(value STREQUAL "NEW") + set(value "TRUE") + else() + set(value "FALSE") + endif() + string(REPLACE "${CMAKE_MATCH_0}" "${value}" lib "${lib}") + endwhile() + + # Fix up $<TARGET_PROPERTY:FOO> expressions that refer to the "current" target. + # Those cannot be used with add_custom_command. + while(lib MATCHES "\\$<TARGET_PROPERTY:([^,>]+)>") + string(REPLACE "${CMAKE_MATCH_0}" "$<TARGET_PROPERTY:${target},${CMAKE_MATCH_1}>" + lib "${lib}") + endwhile() + + # Skip static plugins. + set(_is_plugin_marker_genex "\\$<BOOL:QT_IS_PLUGIN_GENEX>") + if(lib MATCHES "${_is_plugin_marker_genex}") + continue() + endif() + + # Skip optional dependencies for now. They are likely to be handled manually for prl + # file purposes (like nolink handling). And for one of the other operations, we don't + # have a use case yet. This might be revisited. + if(lib MATCHES "^\\$<TARGET_NAME_IF_EXISTS:") + continue() + endif() + + # Strip any directory scope tokens. + __qt_internal_strip_target_directory_scope_token("${lib}" lib) + + if(lib MATCHES "^\\$<TARGET_OBJECTS:") + # Skip object files. + continue() + elseif(lib MATCHES "^\\$<LINK_ONLY:(.*)>$") + set(lib_target ${CMAKE_MATCH_1}) + else() + set(lib_target ${lib}) + endif() + + # Skip CMAKE_DIRECTORY_ID_SEP. If a target_link_libraries is applied to a target + # that was defined in a different scope, CMake appends and prepends a special directory + # id separator. Filter those out. + if(lib_target MATCHES "^::@") + continue() + elseif(TARGET ${lib_target}) + if ("${lib_target}" MATCHES "^Qt::(.*)") + # If both, Qt::Foo and Foo targets exist, prefer the target name without + # namespace. Which one is preferred doesn't really matter. This code exists to + # avoid ending up with both, Qt::Foo and Foo in our dependencies. + set(namespaceless_lib_target "${CMAKE_MATCH_1}") + if(TARGET "${namespaceless_lib_target}") + set(lib_target ${namespaceless_lib_target}) + endif() + endif() + get_target_property(lib_target_type ${lib_target} TYPE) + if(lib_target_type STREQUAL "INTERFACE_LIBRARY") + if(NOT ${direct}) + __qt_internal_walk_libs( + ${lib_target} + lib_libs_${target} + lib_rcc_objects_${target} + "${dict_name}" "${operation}" ${collected}) + if(lib_libs_${target}) + __qt_internal_merge_libs(libs ${lib_libs_${target}}) + set(is_module 0) + endif() + if(lib_rcc_objects_${target}) + __qt_internal_merge_libs(rcc_objects ${lib_rcc_objects_${target}}) + endif() + else() + __qt_internal_merge_libs(libs ${lib}) + endif() + elseif(NOT lib_target_type STREQUAL "OBJECT_LIBRARY") + + if(operation MATCHES "^(collect|direct)_targets$") + __qt_internal_merge_libs(libs ${lib_target}) + else() + __qt_internal_merge_libs(libs "$<TARGET_LINKER_FILE:${lib_target}>") + endif() + + get_target_property(target_rcc_objects "${lib_target}" _qt_rcc_objects) + if(target_rcc_objects) + __qt_internal_merge_libs(rcc_objects ${target_rcc_objects}) + endif() + + if(NOT ${direct}) + __qt_internal_walk_libs( + ${lib_target} + lib_libs_${target} + lib_rcc_objects_${target} + "${dict_name}" "${operation}" ${collected}) + endif() + if(lib_libs_${target}) + __qt_internal_merge_libs(libs ${lib_libs_${target}}) + endif() + if(lib_rcc_objects_${target}) + __qt_internal_merge_libs(rcc_objects ${lib_rcc_objects_${target}}) + endif() + endif() + if(operation STREQUAL "promote_global") + set(lib_target_unaliased "${lib_target}") + get_target_property(aliased_target ${lib_target} ALIASED_TARGET) + if(aliased_target) + set(lib_target_unaliased ${aliased_target}) + endif() + + get_property(is_imported TARGET ${lib_target_unaliased} PROPERTY IMPORTED) + + # Allow opting out of promotion. This is useful in certain corner cases + # like with WrapLibClang and Threads in qttools. + qt_internal_should_not_promote_package_target_to_global( + "${lib_target_unaliased}" should_not_promote) + if(is_imported AND NOT should_not_promote) + __qt_internal_promote_target_to_global(${lib_target_unaliased}) + endif() + endif() + elseif("${lib_target}" MATCHES "^Qt::(.*)") + message(FATAL_ERROR "The ${CMAKE_MATCH_1} target is mentioned as a dependency for \ +${target}, but not declared.") + else() + if(NOT operation MATCHES "^(collect|direct)_targets$") + set(final_lib_name_to_merge "${lib_target}") + if(lib_target MATCHES "/([^/]+).framework$") + set(final_lib_name_to_merge "-framework ${CMAKE_MATCH_1}") + endif() + __qt_internal_merge_libs(libs "${final_lib_name_to_merge}") + endif() + endif() + endforeach() + __qt_internal_memoize_values_in_dict("${target}" "${dict_name}" "libs" "${libs}") + __qt_internal_memoize_values_in_dict("${target}" "${dict_name}" + "rcc_objects" "${rcc_objects}") + + endif() + set(${out_var} ${libs} PARENT_SCOPE) + set(${rcc_objects_out_var} ${rcc_objects} PARENT_SCOPE) +endfunction() + +function(__qt_internal_print_missing_dependency_target_warning target dep) + if(QT_SILENCE_MISSING_DEPENDENCY_TARGET_WARNING) + return() + endif() + message(WARNING + "When trying to collect dependencies of target '${target}', " + "the non-existent target '${dep}' was encountered. " + "This can likely be fixed by moving the find_package call that pulls in " + "'${dep}' to the scope of directory '${CMAKE_CURRENT_LIST_DIR}' or higher. " + "This warning can be silenced by setting QT_SILENCE_MISSING_DEPENDENCY_TARGET_WARNING to " + "ON.") +endfunction() + +# Given ${target}, collect all its private dependencies that are CMake targets. +# +# Discards non-CMake-target dependencies like linker flags or file paths. +# Does nothing when given an interface library. +# +# To be used to extract the full list of target dependencies of a library or executable. +function(__qt_internal_collect_all_target_dependencies target out_var) + set(dep_targets "") + + get_target_property(target_type ${target} TYPE) + + if(NOT target_type STREQUAL "INTERFACE_LIBRARY") + get_target_property(link_libs ${target} LINK_LIBRARIES) + if(link_libs) + foreach(lib ${link_libs}) + if(TARGET "${lib}") + list(APPEND dep_targets "${lib}") + + __qt_internal_walk_libs( + "${lib}" + lib_walked_targets + _discarded_out_var + "qt_private_link_library_targets" + "collect_targets") + + foreach(lib_target IN LISTS lib_walked_targets) + if(NOT TARGET "${lib_target}") + __qt_internal_print_missing_dependency_target_warning(${target} + ${lib_target}) + continue() + endif() + list(APPEND dep_targets ${lib_target}) + endforeach() + endif() + endforeach() + endif() + endif() + + list(REMOVE_DUPLICATES dep_targets) + + set(${out_var} "${dep_targets}" PARENT_SCOPE) +endfunction() |