Building upstream clang with emsdk?

[Brion Vibber]

As of a few months ago I was able to locally build upstream clang with emsdk by running:

./emsdk install upstream-clang-master-64bit

This seems to have stopped working somewhere along the line and I get "No tool or SDK found by name upstream-clang-master-64bit"

I know I can install binaries on supported platforms with "latest-upstream", but on unsupported platforms and when making patches to LLVM I need to build from source. Is there a new SDK name for upstream, or some other way to trigger the build? Thanks!

-- brion

[Brion Vibber]

To answer my own question, this appears to have been disabled because it's broken since LLVM changed repository layouts...?

However it's possible to build LLVM oneself, something like this:

git clone https://github.com/llvm/llvm-project.git

cmake \
-DLLVM_ENABLE_PROJECTS="clang;lld" \
-G "Unix Makefiles" \
-DCMAKE_INSTALL_PREFIX=/opt/llvm \
-DLLVM_TARGETS_TO_BUILD='WebAssembly;X86' \
../llvm

(I used /opt/llvm as the target path, you may choose another.) Note I had to explicitly enable the 'lld' project to get the 'wasm-ld' linker to install.

Then do make && make install with suitable parallel jobs option in -j (-j12 on my 6-core/12-thread laptop).

Then set the LLVM_PATH in ~/.emscripten, and I also had to add it manually to PATH.

Now run the rest of the build as usual, with the new clang/llvm/wasm-ld/etc being picked up automatically.

-- brion

[Alon Zakai]

Yeah, I think those broke when upstream LLVM changed to a monorepo, I noticed that at some point. And it's possible we later removed those broken configs in a refactoring, I'm not sure.

If they are useful it would be nice to fix them!

- Alon

--
You received this message because you are subscribed to the Google Groups "emscripten-discuss" group.
To unsubscribe from this group and stop receiving emails from it, send an email to emscripten-disc...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/emscripten-discuss/CAFnWYT%3DCsEbB0QCP71jsy8Th0f%2BqcpVSbkkTKxHWqAc1g%2B7XHA%40mail.gmail.com.