qt5base-lts/cmake/QtFlagHandlingHelpers.cmake

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function(qt_internal_add_linker_version_script target)
qt_parse_all_arguments(arg "qt_internal_add_linker" "" "" "PRIVATE_HEADERS" ${ARGN})
if (TEST_ld_version_script)
set(contents "Qt_${PROJECT_VERSION_MAJOR}_PRIVATE_API {\n qt_private_api_tag*;\n")
foreach(ph ${arg_PRIVATE_HEADERS})
string(APPEND contents " @FILE:${ph}@\n")
endforeach()
string(APPEND contents "};\n")
set(current "Qt_${PROJECT_VERSION_MAJOR}")
if (QT_NAMESPACE STREQUAL "")
set(tag_symbol "qt_version_tag")
else()
set(tag_symbol "qt_version_tag_${QT_NAMESPACE}")
endif()
string(APPEND contents "${current} { *; };\n")
foreach(minor_version RANGE ${PROJECT_VERSION_MINOR})
set(previous "${current}")
set(current "Qt_${PROJECT_VERSION_MAJOR}.${minor_version}")
if (minor_version EQUAL ${PROJECT_VERSION_MINOR})
string(APPEND contents "${current} { ${tag_symbol}; } ${previous};\n")
else()
string(APPEND contents "${current} {} ${previous};\n")
endif()
endforeach()
set(infile "${CMAKE_CURRENT_BINARY_DIR}/${target}.version.in")
set(outfile "${CMAKE_CURRENT_BINARY_DIR}/${target}.version")
file(GENERATE OUTPUT "${infile}" CONTENT "${contents}")
qt_ensure_perl()
add_custom_command(TARGET "${target}" PRE_LINK
COMMAND "${HOST_PERL}" "${QT_MKSPECS_DIR}/features/data/unix/findclasslist.pl" < "${infile}" > "${outfile}"
BYPRODUCTS "${outfile}" DEPENDS "${infile}"
WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}"
COMMENT "Generating version linker script"
)
target_link_options("${target}" PRIVATE "-Wl,--version-script,${outfile}")
endif()
endfunction()
function(qt_internal_add_link_flags_no_undefined target)
if (NOT QT_BUILD_SHARED_LIBS)
return()
endif()
if ((GCC OR CLANG) AND NOT MSVC)
if(CLANG AND QT_FEATURE_sanitizer)
return()
endif()
set(previous_CMAKE_REQUIRED_LINK_OPTIONS ${CMAKE_REQUIRED_LINK_OPTIONS})
set(CMAKE_REQUIRED_LINK_OPTIONS "-Wl,-undefined,error")
check_cxx_source_compiles("int main() {}" HAVE_DASH_UNDEFINED_SYMBOLS)
if(HAVE_DASH_UNDEFINED_SYMBOLS)
set(no_undefined_flag "-Wl,-undefined,error")
endif()
set(CMAKE_REQUIRED_LINK_OPTIONS "-Wl,--no-undefined")
check_cxx_source_compiles("int main() {}" HAVE_DASH_DASH_NO_UNDEFINED)
if(HAVE_DASH_DASH_NO_UNDEFINED)
set(no_undefined_flag "-Wl,--no-undefined")
endif()
set(CMAKE_REQUIRED_LINK_OPTIONS ${previous_CMAKE_REQUIRED_LINK_OPTIONS})
if (NOT HAVE_DASH_UNDEFINED_SYMBOLS AND NOT HAVE_DASH_DASH_NO_UNDEFINED)
message(FATAL_ERROR "Platform linker doesn't support erroring upon encountering undefined symbols. Target:\"${target}\".")
endif()
target_link_options("${target}" PRIVATE "${no_undefined_flag}")
endif()
endfunction()
function(qt_internal_apply_gc_binaries_conditional target visibility)
# Should only be applied when the feature is enabled, aka for static builds.
if(NOT QT_FEATURE_gc_binaries)
return()
endif()
qt_internal_apply_gc_binaries("${target}" "${visibility}")
endfunction()
function(qt_internal_apply_gc_binaries target visibility)
set(possible_visibilities PRIVATE INTERFACE PUBLIC)
list(FIND possible_visibilities "${visibility}" known_visibility)
if (known_visibility EQUAL "-1")
message(FATAL_ERROR "Visibitily setting must be one of PRIVATE, INTERFACE or PUBLIC.")
endif()
if ((GCC OR CLANG) AND NOT WASM AND NOT UIKIT AND NOT MSVC)
if(APPLE)
set(gc_sections_flag "-Wl,-dead_strip")
elseif(SOLARIS)
set(gc_sections_flag "-Wl,-z,ignore")
elseif(LINUX OR BSD OR WIN32 OR ANDROID)
set(gc_sections_flag "-Wl,--gc-sections")
endif()
endif()
if(gc_sections_flag)
target_link_options("${target}" ${visibility} "${gc_sections_flag}")
endif()
if((GCC OR CLANG) AND NOT WASM AND NOT UIKIT AND NOT MSVC)
set(split_sections_flags "-ffunction-sections" "-fdata-sections")
endif()
if(split_sections_flags)
target_compile_options("${target}" ${visibility} ${split_sections_flags})
endif()
endfunction()
function(qt_internal_apply_intel_cet target visibility)
if(NOT QT_FEATURE_intelcet)
return()
endif()
set(possible_visibilities PRIVATE INTERFACE PUBLIC)
list(FIND possible_visibilities "${visibility}" known_visibility)
if (known_visibility EQUAL "-1")
message(FATAL_ERROR "Visibitily setting must be one of PRIVATE, INTERFACE or PUBLIC.")
endif()
if(GCC)
set(flags "-mshstk")
endif()
if(flags)
target_compile_options("${target}" ${visibility} "${flags}")
endif()
endfunction()
function(qt_internal_library_deprecation_level result)
if(WIN32)
# On Windows, due to the way DLLs work, we need to export all functions,
# including the inlines
list(APPEND deprecations "QT_DISABLE_DEPRECATED_BEFORE=0x040800")
else()
# On other platforms, Qt's own compilation goes needs to compile the Qt 5.0 API
list(APPEND deprecations "QT_DISABLE_DEPRECATED_BEFORE=0x050000")
endif()
list(APPEND deprecations "QT_DEPRECATED_WARNINGS_SINCE=0x060000")
set("${result}" "${deprecations}" PARENT_SCOPE)
endfunction()
# Sets the exceptions flags for the given target according to exceptions_on
function(qt_internal_set_exceptions_flags target exceptions_on)
set(_defs "")
set(_flag "")
if(exceptions_on)
if(MSVC)
set(_flag "/EHsc")
endif()
else()
set(_defs "QT_NO_EXCEPTIONS")
if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
set(_flag "/wd4530" "/wd4577")
elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "GNU|AppleClang|InteLLLVM")
set(_flag "-fno-exceptions")
elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
if (MSVC)
set(_flag "/wd4530" "/wd4577")
else()
set(_flag "-fno-exceptions")
endif()
endif()
endif()
target_compile_definitions("${target}" PRIVATE ${_defs})
target_compile_options("${target}" PRIVATE ${_flag})
endfunction()
function(qt_skip_warnings_are_errors target)
get_target_property(target_type "${target}" TYPE)
if(target_type STREQUAL "INTERFACE_LIBRARY")
return()
endif()
set_target_properties("${target}" PROPERTIES QT_SKIP_WARNINGS_ARE_ERRORS ON)
endfunction()
function(qt_skip_warnings_are_errors_when_repo_unclean target)
if(QT_REPO_NOT_WARNINGS_CLEAN)
qt_skip_warnings_are_errors("${target}")
endif()
endfunction()
function(qt_disable_warnings target)
get_target_property(target_type "${target}" TYPE)
if(target_type STREQUAL "INTERFACE_LIBRARY")
return()
endif()
set_target_properties("${target}" PROPERTIES QT_COMPILE_OPTIONS_DISABLE_WARNINGS ON)
endfunction()
function(qt_set_symbol_visibility_preset target value)
get_target_property(target_type "${target}" TYPE)
if(target_type STREQUAL "INTERFACE_LIBRARY")
return()
endif()
set_target_properties("${target}" PROPERTIES C_VISIBILITY_PRESET "${value}")
set_target_properties("${target}" PROPERTIES CXX_VISIBILITY_PRESET "${value}")
set_target_properties("${target}" PROPERTIES OBJC_VISIBILITY_PRESET "${value}")
set_target_properties("${target}" PROPERTIES OBJCXX_VISIBILITY_PRESET "${value}")
endfunction()
function(qt_set_symbol_visibility_hidden target)
qt_set_symbol_visibility_preset("${target}" "hidden")
endfunction()
function(qt_set_language_standards)
## Use the latest standard the compiler supports (same as qt_common.prf)
if (QT_FEATURE_cxx20)
set(CMAKE_CXX_STANDARD 20 PARENT_SCOPE)
else()
set(CMAKE_CXX_STANDARD 17 PARENT_SCOPE)
endif()
if (c_std_11 IN_LIST CMAKE_C_COMPILE_FEATURES)
set(CMAKE_C_STANDARD 11 PARENT_SCOPE)
elseif (c_std_99 IN_LIST CMAKE_C_COMPILE_FEATURES)
set(CMAKE_C_STANDARD 99 PARENT_SCOPE)
endif()
endfunction()
function(qt_set_language_standards_interface_compile_features target)
# Regardless of which C++ standard is used to build Qt itself, require C++17 when building
# Qt applications using CMake (because the Qt header files use C++17 features).
set(cpp_feature "cxx_std_17")
target_compile_features("${target}" INTERFACE ${cpp_feature})
endfunction()
function(qt_set_msvc_cplusplus_options target visibility)
# For MSVC we need to explicitly pass -Zc:__cplusplus to get correct __cplusplus.
# Check qt_config_compile_test for more info.
if(MSVC AND MSVC_VERSION GREATER_EQUAL 1913)
target_compile_options("${target}" ${visibility} "-Zc:__cplusplus" "-permissive-")
endif()
endfunction()
function(qt_enable_utf8_sources target)
set(utf8_flags "")
if(MSVC)
list(APPEND utf8_flags "-utf-8")
endif()
if(utf8_flags)
# Allow opting out by specifying the QT_NO_UTF8_SOURCE target property.
set(genex_condition "$<NOT:$<BOOL:$<TARGET_PROPERTY:QT_NO_UTF8_SOURCE>>>")
set(utf8_flags "$<${genex_condition}:${utf8_flags}>")
target_compile_options("${target}" INTERFACE "${utf8_flags}")
endif()
endfunction()
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
function(qt_internal_enable_unicode_defines)
if(WIN32)
set(no_unicode_condition
"$<NOT:$<BOOL:$<TARGET_PROPERTY:QT_NO_UNICODE_DEFINES>>>")
target_compile_definitions(Platform
INTERFACE "$<${no_unicode_condition}:UNICODE;_UNICODE>")
endif()
endfunction()
# Saves the list of known optimization flags for the current compiler in out_var.
#
# Mostly used for removing them before adding new ones.
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
function(qt_internal_get_all_possible_optimization_flag_values out_var)
set(flag_values "")
set(vars QT_CFLAGS_OPTIMIZE QT_CFLAGS_OPTIMIZE_FULL
QT_CFLAGS_OPTIMIZE_DEBUG QT_CFLAGS_OPTIMIZE_SIZE)
foreach(optimize_var ${vars})
set(value "${${optimize_var}}")
if(value)
list(APPEND flag_values "${value}")
endif()
endforeach()
# Additional flag values which might not be used in qmake mkspecs, but might be set by CMake,
# aka flags that are recognized by the compile which we might want to remove.
if(QT_CFLAGS_OPTIMIZE_VALID_VALUES)
list(APPEND flag_values ${QT_CFLAGS_OPTIMIZE_VALID_VALUES})
endif()
set("${out_var}" "${flag_values}" PARENT_SCOPE)
endfunction()
# Return's the current compiler's optimize_full flags if available.
# Otherwise returns the regular optimization level flag.
function(qt_internal_get_optimize_full_flags out_var)
set(optimize_full_flags "${QT_CFLAGS_OPTIMIZE_FULL}")
if(NOT optimize_full_flags)
set(optimize_full_flags "${QT_CFLAGS_OPTIMIZE}")
endif()
set(${out_var} "${optimize_full_flags}" PARENT_SCOPE)
endfunction()
# Prints the compiler and linker flags for each configuration, language and target type.
#
# Usually it would print the cache variables, but one may also override the variables
# in a specific directory scope, so this is useful for debugging.
#
# Basically dumps either scoped or cached
# CMAKE_<LANG>_FLAGS_CONFIG> and CMAKE_<TYPE>_LINKER_FLAGS_<CONFIG> variables.
function(qt_internal_print_optimization_flags_values)
qt_internal_get_enabled_languages_for_flag_manipulation(languages)
qt_internal_get_configs_for_flag_manipulation(configs)
qt_internal_get_target_link_types_for_flag_manipulation(target_link_types)
qt_internal_print_optimization_flags_values_helper(
"${languages}" "${configs}" "${target_link_types}")
endfunction()
# Helper function for printing the optimization flags.
function(qt_internal_print_optimization_flags_values_helper languages configs target_link_types)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
foreach(lang ${languages})
set(flag_var_name "CMAKE_${lang}_FLAGS")
message(STATUS "${flag_var_name}: ${${flag_var_name}}")
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
message(STATUS "${flag_var_name}: ${${flag_var_name}}")
endforeach()
endforeach()
foreach(t ${target_link_types})
set(flag_var_name "CMAKE_${t}_LINKER_FLAGS")
message(STATUS "${flag_var_name}: ${${flag_var_name}}")
foreach(config ${configs})
set(flag_var_name "CMAKE_${t}_LINKER_FLAGS_${config}")
message(STATUS "${flag_var_name}: ${${flag_var_name}}")
endforeach()
endforeach()
endfunction()
# Saves the list of configs for which flag manipulation will occur.
function(qt_internal_get_configs_for_flag_manipulation out_var)
set(configs RELEASE RELWITHDEBINFO MINSIZEREL DEBUG)
# Opt into additional non-standard configs for flag removal only.
if(QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS)
list(APPEND configs ${QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS})
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
set(${out_var} "${configs}" PARENT_SCOPE)
endfunction()
# Saves the list of target link types for which flag manipulation will occur.
function(qt_internal_get_target_link_types_for_flag_manipulation out_var)
set(target_link_types EXE SHARED MODULE STATIC)
set(${out_var} "${target_link_types}" PARENT_SCOPE)
endfunction()
# Saves list of enabled languages for which it is safe to manipulate compilation flags.
function(qt_internal_get_enabled_languages_for_flag_manipulation out_var)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
# Limit flag modification to c-like code. We don't want to accidentally add incompatible
# flags to MSVC's RC or Swift.
set(languages_to_process ASM C CXX OBJC OBJCXX)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
get_property(globally_enabled_languages GLOBAL PROPERTY ENABLED_LANGUAGES)
set(enabled_languages "")
foreach(lang ${languages_to_process})
if(lang IN_LIST globally_enabled_languages)
list(APPEND enabled_languages "${lang}")
endif()
endforeach()
set(${out_var} "${enabled_languages}" PARENT_SCOPE)
endfunction()
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# Helper function used to update compiler and linker flags further below
function(qt_internal_replace_flags_impl flag_var_name match_string replace_string IN_CACHE)
# This must come before cache variable modification because setting the
# cache variable with FORCE will overwrite the non-cache variable, but
# we need to use the original value on entry to this function.
# Handle an empty input string and an empty match string as a set().
if(match_string STREQUAL "" AND "${${flag_var_name}}" STREQUAL "")
set(${flag_var_name} "${replace_string}" PARENT_SCOPE)
else()
string(REPLACE
"${match_string}" "${replace_string}"
${flag_var_name} "${${flag_var_name}}")
string(STRIP "${${flag_var_name}}" ${flag_var_name})
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endif()
if(IN_CACHE)
# We must not use the non-cache variable's value because toolchain files
# might be appending things to the cache variable's value and storing it
# in a non-cache variable (e.g. Android NDK toolchain file does this).
# Work exclusively on cache variable value only.
get_property(help_text CACHE "${flag_var_name}" PROPERTY HELPSTRING)
# Handle an empty input string and an empty match string as a set().
if(match_string STREQUAL "" AND "$CACHE{${flag_var_name}}" STREQUAL "")
set(${flag_var_name} "${replace_string}" CACHE STRING "${help_text}" FORCE)
else()
set(mod_flags "$CACHE{${flag_var_name}}")
string(REPLACE
"${match_string}" "${replace_string}"
mod_flags "${mod_flags}")
string(STRIP "${mod_flags}" mod_flags)
set(${flag_var_name} "${mod_flags}" CACHE STRING "${help_text}" FORCE)
endif()
endif()
endfunction()
# Helper function used to update compiler and linker flags further below
function(qt_internal_remove_flags_impl flag_var_name flag_values IN_CACHE)
cmake_parse_arguments(arg "REGEX" "" "" ${ARGN})
set(replace_type REPLACE)
if(arg_REGEX)
list(PREPEND replace_type REGEX)
endif()
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# This must come before cache variable modification because setting the
# cache variable with FORCE will overwrite the non-cache variable in this
# function scope, but we need to use the original value before that change.
foreach(flag_value IN LISTS flag_values)
string(${replace_type} "${flag_value}" " " ${flag_var_name} "${${flag_var_name}}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
endforeach()
string(STRIP "${${flag_var_name}}" ${flag_var_name})
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
if(IN_CACHE)
# We must not use the non-cache variable's value because toolchain files
# might be appending things to the cache variable's value and storing it
# in a non-cache variable (e.g. Android NDK toolchain file does this).
# Work exclusively on cache variable value only.
set(mod_flags $CACHE{${flag_var_name}})
foreach(flag_value IN LISTS flag_values)
string(${replace_type} "${flag_value}" " " mod_flags "${mod_flags}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
endforeach()
string(STRIP "${mod_flags}" mod_flags)
get_property(help_text CACHE ${flag_var_name} PROPERTY HELPSTRING)
set(${flag_var_name} "${mod_flags}" CACHE STRING "${help_text}" FORCE)
endif()
endfunction()
# Helper function used to update compiler and linker flags further below
function(qt_internal_add_flags_impl flag_var_name flags IN_CACHE)
# This must come before cache variable modification because setting the
# cache variable with FORCE will overwrite the non-cache variable, but
# we need to use the original value on entry to this function.
set(${flag_var_name} "${${flag_var_name}} ${flags}")
string(STRIP "${${flag_var_name}}" ${flag_var_name})
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
if(IN_CACHE)
# We must not use the non-cache variable's value because toolchain files
# might be appending things to the cache variable's value and storing it
# in a non-cache variable (e.g. Android NDK toolchain file does this).
# Work exclusively on cache variable value only.
set(mod_flags "$CACHE{${flag_var_name}} ${flags}")
string(STRIP "${mod_flags}" mod_flags)
get_property(help_text CACHE ${flag_var_name} PROPERTY HELPSTRING)
set(${flag_var_name} "${mod_flags}" CACHE STRING "${help_text}" FORCE)
endif()
endfunction()
# Removes all known compiler optimization flags for the given CONFIGS, for all enabled 'safe'
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# languages. The flag variables are always updated in the calling scope, even if they did not
# exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# IN_CACHE - remove them from the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# CONFIGS - should be a list of upper case configs like DEBUG, RELEASE, RELWITHDEBINFO.
# LANGUAGES - optional list of languages like 'C', 'CXX', for which to remove the flags
# if not provided, defaults to the list of enabled C-like languages
function(qt_internal_remove_known_optimization_flags)
qt_parse_all_arguments(
arg
"qt_internal_remove_known_optimization_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
""
"CONFIGS;LANGUAGES"
${ARGN})
if(NOT arg_CONFIGS)
message(FATAL_ERROR
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"You must specify at least one configuration for which to remove the flags.")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
if(arg_LANGUAGES)
set(enabled_languages "${arg_LANGUAGES}")
else()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
qt_internal_get_all_possible_optimization_flag_values(flag_values)
set(configs ${arg_CONFIGS})
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_remove_flags_impl(${flag_var_name} "${flag_values}" "${arg_IN_CACHE}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endforeach()
endforeach()
endfunction()
# Removes specified flags from CMAKE_<LANGUAGES>_FLAGS[_CONFIGS] variables
#
# IN_CACHE enables flags removal from CACHE
# CONFIGS list of configurations that need to clear flags. Clears all configs by default if not
# specified.
# LANGUAGES list of LANGUAGES that need clear flags. Clears all languages by default if not
# specified.
# REGEX enables the flag processing as a regular expression.
function(qt_internal_remove_compiler_flags flags)
qt_parse_all_arguments(arg
"qt_internal_remove_compiler_flags"
"IN_CACHE;REGEX"
""
"CONFIGS;LANGUAGES"
${ARGN}
)
if("${flags}" STREQUAL "")
message(WARNING "qt_internal_remove_compiler_flags was called without any flags specified.")
return()
endif()
if(arg_LANGUAGES)
set(languages "${arg_LANGUAGES}")
else()
qt_internal_get_enabled_languages_for_flag_manipulation(languages)
endif()
if(arg_CONFIGS)
set(configs "${arg_CONFIGS}")
else()
message(FATAL_ERROR
"You must specify at least one configuration for which to remove the flags.")
endif()
if(arg_REGEX)
list(APPEND extra_options "REGEX")
endif()
foreach(lang ${languages})
set(flag_var_name "CMAKE_${lang}_FLAGS")
qt_internal_remove_flags_impl(${flag_var_name}
"${flags}"
"${arg_IN_CACHE}"
${extra_options}
)
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
qt_internal_remove_flags_impl(${flag_var_name}
"${flags}"
"${arg_IN_CACHE}"
${extra_options}
)
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
endfunction()
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# Adds compiler flags for the given CONFIGS in the calling scope. Can also update the cache
# if asked to do so. The flag variables are always updated in the calling scope, even if they
# did not exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# FLAGS - should be a single string of flags separated by spaces.
# IN_CACHE - add them to the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# CONFIGS - should be a list of upper case configs like DEBUG, RELEASE, RELWITHDEBINFO.
# LANGUAGES - optional list of languages like 'C', 'CXX', for which to add the flags
# if not provided, defaults to the list of enabled C-like languages
function(qt_internal_add_compiler_flags)
qt_parse_all_arguments(
arg
"qt_internal_add_compiler_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
"FLAGS"
"CONFIGS;LANGUAGES"
${ARGN})
if(NOT arg_CONFIGS)
message(FATAL_ERROR
"You must specify at least one configuration for which to add the flags.")
endif()
if(NOT arg_FLAGS)
message(FATAL_ERROR "You must specify at least one flag to add.")
endif()
if(arg_LANGUAGES)
set(enabled_languages "${arg_LANGUAGES}")
else()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
endif()
set(configs ${arg_CONFIGS})
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_add_flags_impl(${flag_var_name} "${arg_FLAGS}" "${arg_IN_CACHE}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
endfunction()
# Convenience function that adds compiler flags for all release configurations.
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# The flag variables are always updated in the calling scope, even if they did not
# exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# FLAGS - should be a single string of flags separated by spaces.
# IN_CACHE - add them to the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# LANGUAGES - optional list of languages like 'C', 'CXX', for which to add the flags
# if not provided, defaults to the list of enabled C-like languages
function(qt_internal_add_compiler_flags_for_release_configs)
qt_parse_all_arguments(
arg
"qt_internal_add_compiler_flags_for_release_configs"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
"FLAGS"
"LANGUAGES"
${ARGN})
set(args "")
if(arg_LANGUAGES)
set(enabled_languages "${arg_LANGUAGES}")
else()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
endif()
set(configs RELEASE RELWITHDEBINFO MINSIZEREL)
list(APPEND args CONFIGS ${configs})
if(arg_FLAGS)
list(APPEND args FLAGS "${arg_FLAGS}")
endif()
if(arg_IN_CACHE)
list(APPEND args IN_CACHE)
endif()
list(APPEND args LANGUAGES ${enabled_languages})
qt_internal_add_compiler_flags(${args})
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
set("${flag_var_name}" "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
endforeach()
endfunction()
# Convenience function that replaces all optimization flags with the equivalent of '-O3'
# (optimize_full) flag for all release configs.
#
# This is the equivalent of qmake's CONFIG += optimize_full.
# It is meant to be called in a subdirectory scope to enable full optimizations for a particular
# Qt module, like Core or Gui.
function(qt_internal_add_optimize_full_flags)
qt_parse_all_arguments(
arg
"qt_internal_add_optimize_full_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
""
""
${ARGN})
# QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS disables forced full optimization.
if(QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS)
return()
endif()
# Assume that FEATURE_optimize_full has higher priority. But if FEATURE_optimize_full is OFF,
# flags are set by FEATURE_optimize_size should remain unchanged.
if(QT_FEATURE_optimize_size AND NOT QT_FEATURE_optimize_full)
return()
endif()
set(args "")
if(arg_IN_CACHE)
list(APPEND args IN_CACHE)
endif()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
set(configs RELEASE RELWITHDEBINFO)
if(QT_FEATURE_optimize_full) # Assume that FEATURE_optimize_full has higher priority.
list(APPEND configs MINSIZEREL)
endif()
qt_internal_remove_known_optimization_flags(${args} CONFIGS ${configs})
# If the respective compiler doesn't have optimize_full flags, use regular optimization flags.
# Mainly MSVC.
qt_internal_get_optimize_full_flags(optimize_full_flags)
list(APPEND args FLAGS "${optimize_full_flags}")
qt_internal_add_compiler_flags_for_release_configs(${args})
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
set("${flag_var_name}" "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
endforeach()
endfunction()
# Convenience function to replace a compiler flag with another one, for the given configurations
# for all enabled 'safe' languages.
# Essentially a glorified string(REPLACE).
# Can be used to remove compiler flags.
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# The flag variables are always updated in the calling scope, even if they did not
# exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# match_string - string to match
# replace_string - replacement string
# IN_CACHE - replace them in the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# CONFIGS - should be a list of upper case configs like DEBUG, RELEASE, RELWITHDEBINFO.
# LANGUAGES - optional list of languages like 'C', 'CXX', for which to replace the flags
# if not provided, defaults to the list of enabled C-like languages
function(qt_internal_replace_compiler_flags match_string replace_string)
qt_parse_all_arguments(
arg
"qt_internal_replace_compiler_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
""
"CONFIGS;LANGUAGES"
${ARGN})
if(NOT arg_CONFIGS)
message(FATAL_ERROR
"You must specify at least one configuration for which to replace the flags.")
endif()
if(arg_LANGUAGES)
set(enabled_languages "${arg_LANGUAGES}")
else()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
endif()
set(configs ${arg_CONFIGS})
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_replace_flags_impl(${flag_var_name}
"${match_string}" "${replace_string}" "${arg_IN_CACHE}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
endfunction()
# Convenience function to add linker flags, for the given configurations and target link types.
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# The flag variables are always updated in the calling scope, even if they did not exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# FLAGS - should be a single string of flags separated by spaces.
# IN_CACHE - add them to the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# CONFIGS - should be a list of upper case configs like DEBUG, RELEASE, RELWITHDEBINFO.
# TYPES - should be a list of target link types as expected by CMake's
# CMAKE_<LINKER_TYPE>_LINKER_FLAGS_<CONFIG> cache variable.
# e.g EXE, MODULE, SHARED, STATIC.
function(qt_internal_add_linker_flags)
qt_parse_all_arguments(
arg
"qt_internal_add_linker_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
"FLAGS"
"CONFIGS;TYPES"
${ARGN})
if(NOT arg_TYPES)
message(FATAL_ERROR
"You must specify at least one linker target type for which to add the flags.")
endif()
if(NOT arg_CONFIGS)
message(FATAL_ERROR
"You must specify at least one configuration for which to add the flags.")
endif()
if(NOT arg_FLAGS)
message(FATAL_ERROR "You must specify at least one flag to add.")
endif()
set(configs ${arg_CONFIGS})
set(target_link_types ${arg_TYPES})
foreach(config ${configs})
foreach(t ${target_link_types})
set(flag_var_name "CMAKE_${t}_LINKER_FLAGS_${config}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_add_flags_impl(${flag_var_name} "${arg_FLAGS}" "${arg_IN_CACHE}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
endfunction()
# Convenience function to replace a linker flag with another one, for the given configurations
# and target link types.
# Essentially a glorified string(REPLACE).
# Can be used to remove linker flags.
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# The flag variables are always updated in the calling scope, even if they did not exist beforehand.
#
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# match_string - string to match
# replace_string - replacement string
# IN_CACHE - replace them in the corresponding cache variable too. Note that the cache
# variable may have a different value to the non-cache variable.
# CONFIGS - should be a list of upper case configs like DEBUG, RELEASE, RELWITHDEBINFO.
# TYPES - should be a list of target link types as expected by CMake's
# CMAKE_<LINKER_TYPE>_LINKER_FLAGS_<CONFIG> cache variable.
# e.g EXE, MODULE, SHARED, STATIC.
function(qt_internal_replace_linker_flags match_string replace_string)
qt_parse_all_arguments(
arg
"qt_internal_replace_compiler_flags"
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
"IN_CACHE"
""
"CONFIGS;TYPES"
${ARGN})
if(NOT arg_TYPES)
message(FATAL_ERROR
"You must specify at least one linker target type for which to replace the flags.")
endif()
if(NOT arg_CONFIGS)
message(FATAL_ERROR
"You must specify at least one configuration for which to replace the flags.")
endif()
set(configs ${arg_CONFIGS})
set(target_link_types ${arg_TYPES})
foreach(config ${configs})
foreach(t ${target_link_types})
set(flag_var_name "CMAKE_${t}_LINKER_FLAGS_${config}")
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_replace_flags_impl(${flag_var_name}
"${match_string}" "${replace_string}" "${arg_IN_CACHE}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
endfunction()
# This function finds the optimization flags set by the default CMake platform modules or toolchain
# files and replaces them with flags that Qt qmake builds expect, for all the usual
# CMAKE_BUILD_TYPE configurations.
# This normalizes things like using -O2 for both Release and RelWithDebInfo, among other compilation
# flags. Also some linker flags specific to MSVC.
# See QTBUG-85992 for details.
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
#
# Note that both the calling scope and the CMake cache are updated.
function(qt_internal_set_up_config_optimizations_like_in_qmake)
# Allow opt out.
if(QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS)
return()
endif()
qt_internal_get_enabled_languages_for_flag_manipulation(enabled_languages)
qt_internal_get_configs_for_flag_manipulation(configs)
qt_internal_get_target_link_types_for_flag_manipulation(target_link_types)
# You can set QT_DEBUG_OPTIMIZATION_FLAGS to see the before and after results.
if(QT_DEBUG_OPTIMIZATION_FLAGS)
message(STATUS "")
message(STATUS "DEBUG: Original CMake optimization flags.\n")
qt_internal_print_optimization_flags_values_helper("${enabled_languages}" "${configs}"
"${target_link_types}")
endif()
# Remove known optimization flags.
qt_internal_remove_known_optimization_flags(IN_CACHE CONFIGS ${configs})
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
# Re-add optimization flags as per qmake mkspecs.
foreach(lang ${enabled_languages})
foreach(config ${configs})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
set(value_to_append "")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
# Release and RelWithDebInfo should get the same base optimization flags.
if(config STREQUAL "RELEASE" AND QT_CFLAGS_OPTIMIZE)
set(value_to_append "${QT_CFLAGS_OPTIMIZE}")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
elseif(config STREQUAL "RELWITHDEBINFO" AND QT_CFLAGS_OPTIMIZE)
set(value_to_append "${QT_CFLAGS_OPTIMIZE}")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
# MinSizeRel should get the optimize size flag if available, otherwise the regular
# release flag.
elseif(config STREQUAL "MINSIZEREL")
if(QT_CFLAGS_OPTIMIZE_SIZE)
set(value_to_append "${QT_CFLAGS_OPTIMIZE_SIZE}")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
else()
set(value_to_append "${QT_CFLAGS_OPTIMIZE}")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
endif()
# Debug should get the OPTIMIZE_DEBUG flag if the respective feature is ON.
if(config STREQUAL "DEBUG" AND QT_FEATURE_optimize_debug)
set(value_to_append "${QT_CFLAGS_OPTIMIZE_DEBUG}")
endif()
set(configs_for_optimize_size RELEASE RELWITHDEBINFO)
if(QT_FEATURE_optimize_size AND config IN_LIST configs_for_optimize_size)
set(value_to_append "${QT_CFLAGS_OPTIMIZE_SIZE}")
endif()
# Check if the fake 'optimize_full' feature is enabled.
# Use the max optimization level flag for all release configs, effectively
# overriding any previous setting.
set(configs_for_optimize RELEASE RELWITHDEBINFO MINSIZEREL)
if(QT_FEATURE_optimize_full AND config IN_LIST configs_for_optimize)
qt_internal_get_optimize_full_flags(optimize_full_flags)
set(value_to_append "${optimize_full_flags}")
endif()
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
# Assign value to the cache entry.
if(value_to_append)
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
qt_internal_add_flags_impl(${flag_var_name} "${value_to_append}" TRUE)
# Delay updating the calling scope's variables to the end of this function
endif()
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endforeach()
endforeach()
if(MSVC)
# Handle MSVC /INCREMENTAL flag which should not be enabled for Release configurations.
# First remove them from all configs, and re-add INCREMENTAL for Debug only.
set(flag_values "/INCREMENTAL:YES" "/INCREMENTAL:NO" "/INCREMENTAL")
foreach(flag_value ${flag_values})
qt_internal_replace_linker_flags(
"${flag_value}" ""
CONFIGS ${configs}
TYPES ${target_link_types}
IN_CACHE)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endforeach()
set(flag_value "/INCREMENTAL:NO")
qt_internal_add_linker_flags(
FLAGS "${flag_value}"
CONFIGS RELEASE RELWITHDEBINFO MINSIZEREL
TYPES EXE SHARED MODULE # when linking static libraries, link.exe can't recognize this parameter, clang-cl will error out.
IN_CACHE)
qt_internal_remove_compiler_flags("(^| )/EH[scra-]*( |$)" LANGUAGES CXX CONFIGS ${configs} IN_CACHE REGEX)
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
# Allow opting into generating debug info in object files with a fake feature.
# This would allow us to enable caching with sccache.
# See QTQAINFRA-3934 for details.
if(MSVC AND QT_FEATURE_msvc_obj_debug_info)
qt_internal_replace_compiler_flags(
"/Zi" "/Z7"
CONFIGS RELWITHDEBINFO DEBUG
TYPES ${target_link_types}
IN_CACHE)
endif()
Prevent compiler and linker flags from growing every cmake run Functions in QtFlagHandlingHelpers.cmake try to update the CMake cache variables for compiler and linker flags. These were using the current value of those variables and writing the modified ones back to the cache every time CMake ran. If a toolchain file sets or modifies any of these variables, that updated value is used and written back into the cache instead of the original cache variable's value. The next time CMake executes, the toolchain file re-applies the same change and the variable grows longer each time with flags repeated. With Ninja, this causes a complete rebuild every time CMake is re-run. The Android NDK toolchain file is one example where this behavior is triggered (the fault is shared, one could argue that the NDK should only be setting ..._INIT variables, but that's out of our control). Another related bug in the previous implementation was that the flags used to build after the first CMake execution could be different to those used for all builds after the second and later CMake runs. This is because the CMake cache was being updated, but not always the calling scope of the functions that modified them. If a toolchain file set any of the compiler or linker flag variables as non-cache variables, then updating the cache variable would have no effect on the calling scope. The non-cache variable would continue to take precedence for that scope for that run. The next time CMake executes though, the updated cache variable would now have been used by the toolchain file and the change *will* be part of the non-cache variable's value. The above are examples of why you should try to avoid updating these cache variables from project code. We could leave the cache alone and always update only non-cache variables, but then a developer looking at the cache may wonder why the values they see there don't match the values being used in builds. Or worse, they think the cache values are being used and don't realize the builds are using something different. Ultimately, we have to choose which downside we are happy to live with. The changes here preserve the previous intent of updating the cache, but it's still a bit fragile. Fixes: QTBUG-89821 Task-number: QTBUG-85992 Task-number: QTBUG-86866 Change-Id: I8a16753e159bde338e6d2e5dd2ce91fc8ac5c39d Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
2021-01-07 05:53:43 +00:00
# Update all relevant flags in the calling scope
foreach(config ${configs})
foreach(lang ${enabled_languages})
set(flag_var_name "CMAKE_${lang}_FLAGS_${config}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
foreach(t ${target_link_types})
set(flag_var_name "CMAKE_${t}_LINKER_FLAGS_${config}")
set(${flag_var_name} "${${flag_var_name}}" PARENT_SCOPE)
endforeach()
endforeach()
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
if(QT_DEBUG_OPTIMIZATION_FLAGS)
message(STATUS "")
message(STATUS "DEBUG: Modified optimization flags to mirror qmake mkspecs.\n")
qt_internal_print_optimization_flags_values_helper("${enabled_languages}" "${configs}"
"${target_link_types}")
CMake: Adjust compiler flag optimizations to qmake mkspec ones There are inconsistencies in the default optimization flags added by CMake across configurations like Release and RelWithDebInfo. In particular Release uses -O3, whereas RelWithDebInfo uses -O2, as well as usage of /INCREMENTAL in release configs with MSVC, etc. To make sure that the Qt 6 binaries built with CMake are consistent across configs, as well as consistent with the flags we used when building Qt 5 with qmake, add a horrible search and replace mechanism to replaces the CMake flags with what our mkspecs indicate to use. Ideally this would be done by providing custom CMake toolchain files for each platform we support, and we might revisit that later if the need really arises. To implement the replacing, we first need the flags that should be added. Port the QMAKE_CFLAGS_OPTIMIZE variables to CMake, which is done in QtCompilerOptimization.cmake. Then a new function called qt_internal_set_up_config_optimizations_like_in_qmake will look for any kind of optimization flags set in the CMAKE_<LANG>_FLAGS_<CONFIG> style variables, remove them, and add the appropriate flags that qmake mkspecs provide. On some platforms (like Windows MSVC) the function also alters the linker CMAKE_${TYPE}_LINKER_FLAGS_<CONFIG> style variables. The mechanism allows opting out of this replacing by setting the QT_USE_DEFAULT_CMAKE_OPTIMIZATION_FLAGS value. It also allows opting into removal of flags for custom configs by providing QT_ADDITIONAL_OPTIMIZATION_FLAG_CONFIGS. It's only removal, because we wouldn't know what kind of config it is, and thus what flags to add. The currently modified configs are: Release, RelWithDebInfo, MinSizeRel, Debug aka the usual default CMake provided ones. The mechanism is only applied to C-like languages. ASM is not handled to be on the safe side due to not knowing what kind of compiler flags the platform assembler might take. It's also important to skip RC on MSVC platforms. Task-number: QTBUG-85992 Change-Id: I3712d5cd5a34fceab54f56a6fa46b4e678952362 Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Cristian Adam <cristian.adam@qt.io>
2020-08-17 15:32:28 +00:00
endif()
endfunction()