Introduce a new feature called 'FEATURE_msvc_obj_debug_info' which
should allow usage of sccache for Windows MSVC configs.
Enabling the feature will replace the default '/Zi' compile flag
that CMake sets in Windows-MSVC.cmake with '/Z7'.
This ensures that the debug info is placed into the compiled object
file instead of placing it in the compilation .pdb file via
mspdbsrv.exe.
The final pdb file will still be created for shared libraries and
executables due to the linker '/debug' flag.
Static libraries will not have a .pdb file, instead the debug info
being embeeded in the .lib file.
The downsides of using '/Z7' are more disk space usage, slower
link times, more memory used for linking because the linker needs
to deal with more symbols.
The upside is that caching each indepedent cl.exe call is possible.
This is what Chromium uses with goma, and Firefox with sccache.
We're not enabling the feature by default to allow easier
testing (and switching it off) in the CI if it proves not to be
feasible.
It will probably have to be disabled at least for building
qtwebengine due to high memory requirements.
Task-number: QTQAINFRA-3934
Change-Id: I89e0e57995e938a780be318d1faec700194aa93f
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Enabling it will force usage of '-O3' flag when building Qt.
If the platform has no '-O3' flag, use '-O2' as a fallback.
Task-number: QTBUG-86866
Change-Id: If13f7de954ba5c01dc9634f06a85529828fe90a9
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Introduce a bunch of helper functions to manipulate compiler
flags and linker flags for the
CMAKE_<LANG>_FLAGS_<CONFIG>
and
CMAKE_<LINK_TYPE>_LINKER_FLAGS_<CONFIG>
CMake variables.
These variables can be assigned and modified either in the cache
or for a specific subdirectory scope, which will apply the flags
only to targets in that scope.
Add qt_internal_add_optimize_full_flags() function which mimics
qmake's CONFIG += optimize_full behavior.
Calling it will force usage of the '-O3' optimization flag on supported
platforms (falling back '-O2' where not supported).
Use the function for the Core and Gui subdirectories, to enable full
optimization for the respective Qt modules as it is done in the qmake
projects.
To ensure that the global qmake-like compiler flags are assigned
eveywhere,
qt_internal_set_up_config_optimizations_like_in_qmake() needs
to be called after Qt global features like optimize_size and
optimize_full are available.
This means that qtbase and its standalone tests need some special
handling in regards to when to call that function.
Task-number: QTBUG-86866
Change-Id: Ic7ac23de0265561cb06a0ba55089b6c0d3347441
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
Apparently the combination of the --no-undefined linker flag together
with ASAN when building on Linux with Clang does not work.
Disable --no-undefined flag in such a scenario. Note that linux-clang
mkspec doesn't add that flag at all, which is why asan builds work
there.
Change-Id: I6167c757ce4be5d2263311bc84e5fb445b0f7c2d
Fixes: QTBUG-86879
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
This configure switch controls the feature 'optimize_size'.
This isn't merely a mapping to CMAKE_BUILD_TYPE=MinSizeRel, because
we potentially want to combine -optimize-size with -force-debug-info,
which maps to CMAKE_BUILD_CONFIG=RelWithDebInfo.
Task-number: QTBUG-85373
Change-Id: I1a9343ebc54816f52e90e9d33ea3df4c99b1ec9f
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
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>
QtBuild.cmake is huge. Split it.
Move module, plugin, tools, executables and test related functions out
of QtBuild.cmake into separate files.
Do the same for many other things too.
An additional requirement is that all the new Helpers files only
define functions and macros.
No global variable definitions are allowed, nor execution of commands
with side effects.
Some notes:
qt_install_qml_files is removed because it's dead code.
Some functions still need to be figured out, because they are
interspersed and depend on various global state assignments.
Task-number: QTBUG-86035
Change-Id: I21d79ff02eef923c202eb1000422888727cb0e2c
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
