With the new behaviour, the /MD or similar options aren't added to
e.g. CMAKE_CXX_FLAGS_RELEASE, but are added separately by CMake.
They can be changed by the cmake variable
CMAKE_MSVC_RUNTIME_LIBRARY or with the target property
MSVC_RUNTIME_LIBRARY.
LLVM has had its own custom CMake flags, e.g. LLVM_USE_CRT_RELEASE,
which affects which CRT is used for release mode builds. Deprecate
these and direct users to use CMAKE_MSVC_RUNTIME_LIBRARY directly
instead (and do a best effort attempt at setting CMAKE_MSVC_RUNTIME_LIBRARY
based on the existing LLVM_USE_CRT_ flags). This only handles the
simple cases, it doesn't handle multi-config generators with
different LLVM_USE_CRT_* variables for different configs though,
but that's probably fine - we should move over to the new upstream
CMake mechanism anyway, and push users towards that.
Change code in compiler-rt, that previously tried to override the
CRT choice to /MT, to set CMAKE_MSVC_RUNTIME_LIBRARY instead of
meddling in the old variables.
This resolves the policy issue in
https://github.com/llvm/llvm-project/issues/63286, and should
handle the issues that were observed originally when the
minimum CMake version was bumped, in
https://github.com/llvm/llvm-project/issues/62719 and
https://github.com/llvm/llvm-project/issues/62739.
Differential Revision: https://reviews.llvm.org/D155233
This reverts commit d763c6e5e2d0a6b34097aa7dabca31e9aff9b0b6.
Adds the patch by @hans from
https://github.com/llvm/llvm-project/issues/62719
This patch fixes the Windows build.
d763c6e5e2d0a6b34097aa7dabca31e9aff9b0b6 reverted the reviews
D144509 [CMake] Bumps minimum version to 3.20.0.
This partly undoes D137724.
This change has been discussed on discourse
https://discourse.llvm.org/t/rfc-upgrading-llvms-minimum-required-cmake-version/66193
Note this does not remove work-arounds for older CMake versions, that
will be done in followup patches.
D150532 [OpenMP] Compile assembly files as ASM, not C
Since CMake 3.20, CMake explicitly passes "-x c" (or equivalent)
when compiling a file which has been set as having the language
C. This behaviour change only takes place if "cmake_minimum_required"
is set to 3.20 or newer, or if the policy CMP0119 is set to new.
Attempting to compile assembly files with "-x c" fails, however
this is workarounded in many cases, as OpenMP overrides this with
"-x assembler-with-cpp", however this is only added for non-Windows
targets.
Thus, after increasing cmake_minimum_required to 3.20, this breaks
compiling the GNU assembly for Windows targets; the GNU assembly is
used for ARM and AArch64 Windows targets when building with Clang.
This patch unbreaks that.
D150688 [cmake] Set CMP0091 to fix Windows builds after the cmake_minimum_required bump
The build uses other mechanism to select the runtime.
Fixes#62719
Reviewed By: #libc, Mordante
Differential Revision: https://reviews.llvm.org/D151344
This reverts commit 65429b9af6a2c99d340ab2dcddd41dab201f399c.
Broke several projects, see https://reviews.llvm.org/D144509#4347562 onwards.
Also reverts follow-up commit "[OpenMP] Compile assembly files as ASM, not C"
This reverts commit 4072c8aee4c89c4457f4f30d01dc9bb4dfa52559.
Also reverts fix attempt "[cmake] Set CMP0091 to fix Windows builds after the cmake_minimum_required bump"
This reverts commit 7d47dac5f828efd1d378ba44a97559114f00fb64.
Move `cmake_policy()` settings from `llvm/CMakeLists.txt` into a shared
`cmake/modules/CMakePolicy.cmake`. Include it from all relevant
projects that support standalone builds, in order to ensure that
the policies are consistently set whether they are built in-tree
or stand-alone.
Differential Revision: https://reviews.llvm.org/D136572
This reverts commit 88d7508dc479210f07abccb17f0194b66264b125.
It's reported to break builds when symlinking other projects inside
the `tools` directory.
Move `cmake_policy()` settings from `llvm/CMakeLists.txt` into a shared
`cmake/modules/CMakePolicy.cmake`. Include it from all relevant
projects that support standalone builds, in order to ensure that
the policies are consistently set whether they are built in-tree
or stand-alone.
Differential Revision: https://reviews.llvm.org/D136572
