The target property `ISPC_HEADER_SUFFIX` and associated global
variable now can control the suffix used when generating the
C/C++ interoperability ISPC headers.
In addition the default suffix is now "_ispc.h" which matches the
common convention that the ISPC compiler team uses and recommends.
b7f0327dcd Tests: Cover macOS host architecture selection on Apple Silicon hosts
5f882f6ce5 macOS: Offer control over host architecture on Apple Silicon hosts
Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !5589
Since commit b6c60f14b6 (macOS: Default to arm64 architecture on Apple
Silicon hosts, 2020-09-28, v3.19.0-rc1~63^2) we use `sysctl` to detect
that we are running on Apple Silicon in a way that pierces Rosetta.
This always sets `CMAKE_HOST_SYSTEM_PROCESSOR` to be `arm64` on such
hosts. However, macOS offers strong support for running processes under
an emulated `x86_64` architecture.
Teach CMake to select either `arm64` or `x86_64` as the host
architecture on Apple Silicon based on the architecture of its own
process. When CMake is built as a universal binary, macOS will select
whichever slice (architecture) is appropriate under the user's shell,
and `CMAKE_HOST_SYSTEM_PROCESSOR` will match.
Also offer a `CMAKE_APPLE_SILICON_PROCESSOR` variable and environment
variable to provide users with explicit control over the host
architecture selection regardless of CMake's own architecture.
Finally, if `CMAKE_OSX_ARCHITECTURES` is not set, pass explicit flags to
the toolchain to use selected host architecture instead of letting the
toolchain pick.
Fixes: #21554
If a path argument with no -S or -B leads to a cache directory,
use that directory as the binary directory. Otherwise, use the
binary directory from the preset.
Fixes: #21311
Make this field separate for both architecture and toolset. Allow
architecture and toolset to be either strings or objects with value
and strategy fields.
Fixes: #21317
The TI compiler does not support C++98, only C++03
(based on manual of current version).
This change sets the C++98 option to C++03 based on the fact that it
is done this way for the SunPro compiler already.
Extend the `-T <toolset>` option to support a `buildsystem=` field with
the Xcode generator. Add a `CMAKE_XCODE_BUILD_SYSTEM` variable to
inform project code about the selected build system variant.
`ExternalProject_Add_StepTargets` and `INDEPENDENT_STEP_TARGETS` have
some limitations and lack some sanity checks. They can cause confusing
build systems to be generated. The basic problems are:
* The notion of step independence is attached to the step target
rather than the step itself.
* The custom commands implementing the steps are duplicated in the
step targets and the primary targets. This can cause races.
It is also incompatible with the Xcode "new build system".
Fix this by introducing policy CMP0114 to change the way step target
dependencies are handled. Define independence from external
dependencies as a property of each individual step regardless of whether
there is a target for it. Add dependencies among the primary target and
the step targets such that each custom command only appears in one
target. When some steps are disconnected from the primary target, add
step targets for the steps commonly depended upon so that there is a
place to hold their custom commands uniquely.
Fixes: #18663
Do not attach a custom command to a target if it is already attached to one of
the target's dependencies. The command's output will be available by the time
the target needs it because the dependency containing the command will have
already been built.
This may break existing projects that do not properly mark non-created
outputs with the `SYMBOLIC` property. Previously a chain of two custom
commands whose intermediate dependency is not created would put both
commands in a dependent project's Makefile even if the first command is
also in its dependency's Makefile. The first command would run twice
but the build would work. Now the second command needs an explicit
`SYMBOLIC` mark on its input to tell CMake that it is not expected to
exist. To maintain compatibility with projects that left out the mark,
add a policy activating the behavior.
Robert Maynard