This document describes how to compile LLVM distribution and use it to build Kotlin/Native on macOS.
Usually, you don't need to compile LLVM by yourself: it is downloaded automatically when you run or build Kotlin/Native compiler.
But if you don't want to download prebuilt LLVM or want to experiment with your own distribution, you came to the right place.
For macOS host we use LLVM from Apple downstream. Branch is apple/stable/20190104 because it is similar (or even the same) to what Apple ships with Xcode 11.*. After cloning the repo and changing the branch we perform the following steps to build LLVM toolchain:
mkdir build cd build cmake -DLLVM_ENABLE_PROJECTS="clang;lld;libcxx;libcxxabi" \ -DCMAKE_BUILD_TYPE=Release \ -DLLVM_ENABLE_ASSERTIONS=Off \ -G Ninja \ -DCMAKE_INSTALL_PREFIX=clang-llvm-apple-8.0.0-darwin-macos \ ../llvm ninja install
After these steps clang-llvm-apple-8.0.0-darwin-macos
directory will contain LLVM distribution that is suitable for building Kotlin/Native.
By default, Kotlin/Native will try to download LLVM distribution from CDN if it is not present in $HOME/.konan/dependencies
folder. There are two ways to bypass this behaviour.
This option doesn't require you to edit compiler sources, but a bit harder.
The compiler checks dependency presence by reading contents of $HOME/.konan/dependencies/.extracted
file. So to avoid LLVM downloading, we should manually add a record to the .extracted
file:
$HOME/.konan/dependencies/.extracted
file if it is not created.clang-llvm-apple-8.0.0-darwin-macos
line.and put clang-llvm-apple-8.0.0-darwin-macos
directory from the Part 1 to $HOME/.konan/dependencies/
.
This option requires user to edit konan.properties file. Set llvmHome.<HOST_NAME>
to an absolute path to your LLVM distribution and set llvmVersion.<HOST_NAME>
to its version. For example, provide a path to clang-llvm-apple-8.0.0-darwin-macos
from the Part 1 and set version to 8.0.0.
Now we are ready to build Kotlin/Native itself. The process is described in README.md.
— Can I override .konan
location?
— Yes, by setting $KONAN_DATA_DIR
environment variable. See HACKING.md.