qt5base-lts/cmake/QtFinishPrlFile.cmake
Alexandru Croitor 754512a64d CMake: Fix prl files not to contain hard-coded library paths
Make sure to convert absolute paths generated using the
$<TARGET_LINKER_FILE> generator expressions into relative paths.

Because prl files are generated for both modules and plugins, we need
to pass both a list of qt module locations and qt plugin locations
to QtFinishPrl.cmake, and then try to make the absolute path relative
to each passed directory.

A warning assertion is shown if we no relative path could be made,
which will cause an absolute path to be embedded. This should not
happen though.

Amends f4e9981259

Pick-to: 6.2 6.3 6.4
Fixes: QTBUG-104396
Change-Id: Id68395c0dbb20aad5c510d77835cc931b9396556
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>
2022-06-22 20:18:39 +02:00

140 lines
7.1 KiB
CMake

# Finish a preliminary .prl file.
#
# - Replaces occurrences of the build libdir with $$[QT_INSTALL_LIBDIR].
# - Strips version number suffixes from absolute paths, because qmake's lflag
# merging does not handle them correctly.
# - Transforms absolute library paths into link flags
# aka from "/usr/lib/x86_64-linux-gnu/libcups.so" to "-lcups"
# - Replaces Qt absolute framework paths into a combination of -F$$[QT_INSTALL_LIBS] and
# -framework QtFoo
# - Prepends '-l' to values that are not absolute paths, and don't start with a dash
# aka, '-lfoo', '-framework', '-pthread'.
#
# The path to the final .prl file is stored in the input file as assignment to FINAL_PRL_FILE_PATH.
#
# This file is to be used in CMake script mode with the following variables set:
# IN_FILE: path to the step 1 preliminary .prl file
# OUT_FILE: path to the step 2 preliminary .prl file that is going to be created
# QT_LIB_DIRS: list of paths where Qt libraries are located.
# This includes the install prefix and the current repo build dir.
# These paths get replaced with relocatable paths or linker / framework flags.
# LIBRARY_SUFFIXES: list of known library extensions, e.g. .so;.a on Linux
# LIBRARY_PREFIXES: list of known library prefies, e.g. the "lib" in "libz" on on Linux
# LINK_LIBRARY_FLAG: flag used to link a shared library to an executable, e.g. -l on UNIX
# IMPLICIT_LINK_DIRECTORIES: list of implicit linker search paths
cmake_policy(SET CMP0007 NEW)
include("${CMAKE_CURRENT_LIST_DIR}/QtGenerateLibHelpers.cmake")
file(STRINGS "${IN_FILE}" lines)
set(content "")
set(qt_framework_search_path_inserted FALSE)
foreach(line ${lines})
if(line MATCHES "^RCC_OBJECTS = (.*)")
set(rcc_objects ${CMAKE_MATCH_1})
elseif(line MATCHES "^QMAKE_PRL_TARGET_PATH_FOR_CMAKE = (.*)")
set(target_library_path "${CMAKE_MATCH_1}")
elseif(line MATCHES "^QMAKE_PRL_LIBS_FOR_CMAKE = (.*)")
unset(adjusted_libs)
foreach(lib ${CMAKE_MATCH_1})
if("${lib}" STREQUAL "")
continue()
endif()
# Check if the absolute path represents a Qt module located either in Qt's
# $prefix/lib dir, or in the build dir of the repo.
if(IS_ABSOLUTE "${lib}")
qt_internal_path_is_relative_to_qt_lib_path(
"${lib}" "${QT_LIB_DIRS}" lib_is_a_qt_module relative_lib)
if(NOT lib_is_a_qt_module)
# It's not a Qt module, extract the library name and prepend an -l to make
# it relocatable.
qt_transform_absolute_library_paths_to_link_flags(lib_with_link_flag "${lib}")
list(APPEND adjusted_libs "${lib_with_link_flag}")
else()
# Is a Qt module.
# Transform Qt framework paths into -framework flags.
if(relative_lib MATCHES "^(Qt(.+))\\.framework/")
if(NOT qt_framework_search_path_inserted)
set(qt_framework_search_path_inserted TRUE)
list(APPEND adjusted_libs "-F$$[QT_INSTALL_LIBS]")
endif()
list(APPEND adjusted_libs "-framework" "${CMAKE_MATCH_1}")
else()
# Not a framework, transform the Qt module into relocatable relative path.
qt_strip_library_version_suffix(relative_lib "${relative_lib}")
list(APPEND adjusted_libs "$$[QT_INSTALL_LIBS]/${relative_lib}")
endif()
endif()
else()
# Not absolute path, most likely a library name or a linker flag.
# If linker flag (like -framework, -lfoo, -pthread, keep it as-is).
if(NOT lib MATCHES "^-")
string(PREPEND lib "-l")
endif()
list(APPEND adjusted_libs "${lib}")
endif()
endforeach()
if(rcc_objects)
set(libs_to_prepend ${rcc_objects})
# By default, when qmake processes prl files, it first puts the processed library
# on the link line, followed by all values specified in QMAKE_PRL_LIBS.
# Because we add the resource object files into QMAKE_PRL_LIBS, this means they will
# also appear on the link line after the library.
# This causes issues on Linux because the linker may discard unreferenced symbols from
# the library, which are referenced by the resource object files.
# We can't control the placement of the library in relation to QMAKE_PRL_LIBS, but we
# can add the library one more time in QMAKE_PRL_LIBS, after the object files.
# qmake's UnixMakefileGenerator::findLibraries then takes care of deduplication, which
# keeps the last occurrence of the library on the link line, the one after the object
# files.
qt_internal_path_is_relative_to_qt_lib_path(
"${target_library_path}" "${QT_LIB_DIRS}" lib_is_a_qt_module relative_lib)
if(NOT lib_is_a_qt_module)
qt_internal_path_is_relative_to_qt_lib_path(
"${target_library_path}" "${QT_PLUGIN_DIRS}" lib_is_a_qt_plugin relative_lib)
endif()
if(NOT lib_is_a_qt_module AND NOT lib_is_a_qt_plugin)
message(AUTHOR_WARNING
"Could not determine relative path for library ${target_library_path} when "
"generating prl file contents. An absolute path will be embedded, which "
"will cause issues if the Qt installation is relocated.")
list(APPEND libs_to_prepend "${target_library_path}")
else()
set(qmake_lib_path_prefix "$$[QT_PRL_INVALID_QMAKE_VARIABLE]")
if(lib_is_a_qt_module)
set(qmake_lib_path_prefix "$$[QT_INSTALL_LIBS]")
elseif(lib_is_a_qt_plugin)
set(qmake_lib_path_prefix "$$[QT_INSTALL_PLUGINS]")
endif()
qt_strip_library_version_suffix(relative_lib "${relative_lib}")
list(APPEND libs_to_prepend "${qmake_lib_path_prefix}/${relative_lib}")
endif()
list(PREPEND adjusted_libs ${libs_to_prepend})
endif()
list(JOIN adjusted_libs " " adjusted_libs_for_qmake)
string(APPEND content "QMAKE_PRL_LIBS = ${adjusted_libs_for_qmake}\n")
string(APPEND content "QMAKE_PRL_LIBS_FOR_CMAKE = ${adjusted_libs}\n")
else()
string(APPEND content "${line}\n")
endif()
endforeach()
file(WRITE "${OUT_FILE}" "${content}")
# Read the prl meta file to find out where should the final prl file be placed,
# Copy it there, if the contents hasn't changed.
file(STRINGS "${IN_META_FILE}" lines)
foreach(line ${lines})
if(line MATCHES "^FINAL_PRL_FILE_PATH = (.*)")
set(final_prl_file_path "${CMAKE_MATCH_1}")
configure_file(
"${OUT_FILE}"
"${final_prl_file_path}"
COPYONLY
)
endif()
endforeach()