Reland "[CMake] Bumps minimum version to 3.20.0.
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
GitOrigin-RevId: cbaa3597aaf6273e66b3f445ed36a6458143fe6a
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1e9e473..a24330d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.13.4)
+cmake_minimum_required(VERSION 3.20.0)
if(NOT DEFINED LLVM_COMMON_CMAKE_UTILS)
set(LLVM_COMMON_CMAKE_UTILS ${CMAKE_CURRENT_SOURCE_DIR}/../cmake)
@@ -11,13 +11,6 @@
if(CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
project(lld)
set(LLD_BUILT_STANDALONE TRUE)
- if ("${CMAKE_VERSION}" VERSION_LESS "3.20.0")
- message(WARNING
- "Your CMake version is ${CMAKE_VERSION}. Starting with LLVM 17.0.0, the "
- "minimum version of CMake required to build LLVM will become 3.20.0, and "
- "using an older CMake will become an error. Please upgrade your CMake to "
- "at least 3.20.0 now to avoid issues in the future!")
- endif()
endif()
# Must go below project(..)
