07bc3b07ec gitlab-ci: test C++ modules using GCC
1b2270aa4e ci: add a Docker image to test out C++ modules with GCC
8c5a53096a Tests/RunCMake/CXXModules: add module-using examples
4151547e2f cmGlobalNinjaGenerator: use `cmModuleMapper` implementation
b43bdaff3c cmCxxModuleMapper: implement support for GCC's module map format
02d0f0e752 cmCxxModuleMapper: add source to handle module mapper contents
a046a45aad cmGlobalNinjaGenerator: add a TODO for header units
386465bf83 cmTarget: add support for C++ module fileset types
...
Acked-by: Kitware Robot <kwrobot@kitware.com>
Tested-by: buildbot <buildbot@kitware.com>
Merge-request: !7369
C++ modules have two variants which are of importance to CMake:
- `CXX_MODULES`: interface modules (those using `export module M;`,
`export module M:part;`, or `module M:internal_part;`)
- `CXX_MODULE_HEADER_UNITS`: importable header units
Creating C++ modules or partitions are *not* supported in any other
source listing. This is because the source files must be installed (so
their scope matters), but not part of usage requirements (what it means
for a module source to be injected into a consumer is not clear at this
moment). Due to the way `FILE_SET` works with scopes, they are a perfect
fit as long as `INTERFACE` is not allowed (which it is not).
Forward `CMAKE_<LANG>_FLAGS` and `CMAKE_<LANG>_FLAGS_DEBUG` from the
calling project into the test project. The set of flags may affect the
availability of IPO support. Since this may change the result of the
check for existing projects, add a policy for compatibility.
This was discovered after commit 5fcadc481e (MSVC: Default to -ZI
instead of /Zi for x86 and x64, 2022-05-24) introduced policy CMP0138 to
switch our default for MSVC's debug info flag. The `-ZI` flag is
incompatible with the `-GL` flag used for IPO, so CMP0138 was reverted
pending future work on an alternative solution. Re-use the CMP0138
policy number for this change to CheckIPOSupported instead.
Fixes: #23607
Revert commit 5fcadc481e (MSVC: Default to -ZI instead of /Zi for x86
and x64, 2022-05-24). The `-ZI` flag is incompatible with the `-GL`
flag used for IPO, and so is not an unconditionally better default.
Revert the change pending future design of a first-class setting for
MSVC debug info format that can be automatically reconciled with IPO
settings.
That commit introduced policy CMP0138, but we already have later policy
numbers used too. Leave placeholder text to avoid policy renumbering.
Issue: #23607, #10189
The guide previously only focused on the find_package() command,
with a bias towards libraries. FetchContent was not mentioned at all.
Reorganise and update the existing content. Add new sections to cover
providing dependencies with FetchContent and dependency providers.
Improve discoverability of the guide by mentioning it at the beginning
of the find_package(), FetchContent and dependency provider docs.
Projects should always have specified one of PRE_BUILD, PRE_LINK or
POST_BUILD, and the documentation has always shown that one must
be given. But the argument parsing logic was such that if none was given,
POST_BUILD would be used and no error or warning would be raised.
Projects may be relying on this behavior, so document it as formally
supported, but not recommended.
Fixes: #23488
5a9c7f76c0 Help: Document CMake version adding each preset version in cmake-presets(7)
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !7313
Since commit 07223c5c27 (Tutorial: Update Step 5 to work on Windows,
2020-02-18, v3.18.0-rc1~655^2) the logic does not work on non-Windows
platforms when cmake is re-run on an existing build tree. It is also
more complicated than we'd like for a tutorial example. Avoid the need
to consider the `m` library case by performing the check as C++.
Since `check_cxx_symbol_exists` cannot handle overloaded functions
like `exp` and `log`, check with `check_cxx_source_compiles` instead.
This also presents a more general-purpose example in the tutorial.
Fixes: #23524