This commit collects together some LLVM PRs, some changes in the build
configuration here, and some thoughts from #565 and related issues.
Specifically the changes here are:
* The patch for llvm/llvm-project#168449 is updated to its upstream
(unlanded) form.
* Patches for the (landed) llvm/llvm-project#185770 and
llvm/llvm-project#185775 are added.
* The `WASI_SDK_EXCEPTIONS` configuration is now either `ON`, `OFF`, or
`DUAL`. The default depends on the version of Clang in use, where
23.0.0+ (which isn't released officially yet) will be `DUAL` and
otherwise it's `OFF`. CI for our custom-built patched toolchain defaults
to `DUAL`.
* In `DUAL` mode libcxx is built twice into two different directories,
once with exceptions and once without. This is supported by LLVM patches
and means that Clang will select the right set of libraries based on
compiler flags.
The end result here is that the produced toolchain from this repository,
by default, supports C++ exceptions. Additionally if exceptions-related
flags are not passed then the final binary will not use C++ exceptions
nor require the wasm exception-handling proposal.
There's still follow-up work from #565, such as:
* Subjectively it feels wordy to pass `-fwasm-exceptions` vs
`-fexceptions`.
* Personally I think `-mllvm -wasm-use-legacy-eh=false` should become
the default upstream.
* Subjectively I don't think that `-lunwind` should be necessary and it
should be injected automatically with `-fwasm-exceptions` (or
`-fexceptions`).
* Shared libraries for exceptions remain disabled due to build errors I
do not personally know how to resolve.
I'll file follow-up issues for these once this has landed since they're
more minor compared to the main body of "anything works".
Closes#334Closes#565
---------
Co-authored-by: Joel Dice <joel.dice@akamai.com>
* Update for C++ Exceptions being supported.
* Update the threading-related bits slightly.
* Indicate that dynamic linking works but may not be as fully tested.
* Networking works, just not on WASIp1.
> **Note**: this PR is me weaving together the work of many others. For
example @yerzham's and @cpetig's work on #565 pretty much shaped this
PR. Thank you!
This commit adds initial configuration support for building wasi-sdk
with support for C++ exceptions in WebAssembly. A small test is included
which is exercised in CI at this time, but otherwise this does not
update CI to actually ship sdk builds with C++ exceptions enabled.
Instead the intention here is to make it easier to test builds with
support for C++ exceptions and centralize planning/development around
this.
The goal here is to get things compiling to the point that applications
can be compiled. I haven't thoroughly tested C++ exceptions and as
evident in this PR it still requires changes in LLVM. Some small logic
is added here to apply a `*.patch` file to LLVM to avoid needing a new
submodule fork or waiting for upstream changes. The intention is that
this `*.patch` is short-lived once the changes are officially merged
into LLVM itself.
The `*.patch` included here contains llvm/llvm-project#168449 as well as
another minor edit I found was necessary to get things compiling
locally. Given the discussion on that PR it looks like once LLVM is
updated with that merged the extra part of the `*.patch` won't be
necessary.
This PR notably does not enable shared libraries when exceptions are
enabled. I don't know enough about how things are supposed to work to be
able to fully diagnose the compilation errors I'm seeing if shared
libraries are enabled. This is something I'd hope would be fixed before
actually shipping exceptions support.
This PR then additionally folds in [this gist][gist] for various bits of
build logic to this repository itself.
Finally, this PR includes some documentation about the current status of
exceptions and links to various tracking issues too.
[gist]: https://gist.github.com/yerzham/302efcec6a2e82c1e8de4aed576ea29d
Add a cmake option WASI_SDK_CPU_CFLAGS to specify CFLAGS to control wasm
features to enable/disable.
Make the default `-mcpu=lime1`.
Comparing to the default "generic" target of the recent llvm, this
effectively
* disables reference-types and bulk-memory (enable their partial
counterparts instead)
* enables extended-const
Note: as of writing this, a few popular runtimes, including wasm3 and
wasm-micro-runtime,
don't support extented-const yet.
Note: regardless of this, wasi-libc enables necessary features for
certain files. (bulk-memory and exception-handling)
cf. https://github.com/WebAssembly/wasi-sdk/issues/525
References:
https://github.com/WebAssembly/tool-conventions/blob/main/Lime.mdhttps://github.com/bytecodealliance/wasm-micro-runtime/issues/4272
This commit enables thread support in libc++ for all thread models,
enabling C++ applications that use threading APIs like `<atomic>` but do
not spawn threads (e.g. Clang) to be built with minimal changes.
Fixes#546.
Depends on WebAssembly/wasi-libc#602.
This change allows us to have per-target libclang_rt.* libraries instead
of per-OS. This is particularly required for w/threads and wo/threads
targets, whose rt libraries could be incompatible even with the same OS
string.
This change starts building `compiler-rt` for w/threads and wo/threads
separately, so that we can enable thread-related features for p1-threads
target for building upcoming ASan clang_rt libraries. Also
`COMPILER_RT_OS_DIR` is not set anymore as it's unused when
`LLVM_ENABLE_PER_TARGET_RUNTIME_DIR` is enabled.
Hi! I added `WASI_ARCH=arm64` command for the arm64 package version to
the installation command’s comment. I thought this would make the
command more clear.
* Add missing architecture URL part to the installation script
* Remove unnecessary `export`s from installation instructions
* Fix missing $ sign in export
* Add `WASI_OS` as new parameter to use & install scripts in README
---------
Co-authored-by: Andrew Brown <andrew.brown@intel.com>
* Add a CI check for testing toolchains as-distributed
One aspect of testing lost in the CMake-based migration is the ability
to test the toolchains as distributed in release artifacts. Tests use
`--sysroot` and `-resource-dir` (soon) to customize how the host
compiler runs but this means that it would be possible to regress the
default sysroot theoretically. To rectify this situation this commit
adds a new CI test which uses the release artifacts of previous steps to
build a `wasi-sdk-*.tar.gz` tarball which is then extracted and tested
as-is. A new flag was added to the cmake configuration to avoid
depending on fresh sysroot libraries for tests and instead test the host
toolchain.
* Fix version.py script running
* Fix artifact download
* Add ninja
* Update submodules in new test job
* Only add extra options for libcxx build
Otherwise the test directory seems like it inherits these options which
isn't desired when testing the host toolchain.
This changes the front-page documentation to:
- use out-of-line links in more places
- mention the need for `libclang_rt.builtins-wasm32.a` when using
standard Clang
- mention how to use a `wasi-libc` sysroot
- explain the experimental status of `wasm32-wasi-threads
Previously, the release process for wasi-sdk was undocumented and
manual. The `RELEASING.md` document in this commit describes the steps
necessary to publish a new version of `wasi-sdk` as a GitHub release and
provides helpful scripts to automate some of the steps.
With this in place, a future change could add a workflow trigger that
allows running the steps automatically in GitHub actions. Keeping the
steps as scripts in the repository, however, allows developers to re-run
steps themselves in the (likely) case that something goes awry.
This change was mostly generated by changing the upstream llvm
branch to 9.x and running:
$ git submodule update --remote
As well as switching the llvm 9 this change also bring in the
following wasi-libc changes:
5933c20 fix macos filename, use https
7c39519 CI: upgrade to llvm 9.0.0
9ca5187 remove no-self-update workaround for windows azure
9580a25 deprecate azure pipelines CI, build libc on GH Actions
2c2fc9a Don't call `free` on paths which are about to call `_Exit`. (#161)
c6f2c05 gen-headers: Generate assertions of layout from witx (#149)
37c663f Correct minor typo in c_headers.rs (#166)
12f5832 Convert more wasi-libc code to `//`-style comments. (#153)
ec86d4d Improvements to wasi-headers tool (#160)
1fad338 Fix environment variable init to exit successfully. (#159)
a280fea Move math source files. (#151)
dd010be Avoid using cast expressions in WASI API constants. (#148)
Fixes: #101
The wasi-libc update here brings numerous bug fixes and minor changes,
and __wasilibc_rmfileat has been renamed to __wasilibc_unlinkat.
The only WebAssembly-relevant patch in the LLVM 8.0.1 update here is
4b1712f7, a fix for using /dev/null as the output file.
Alex Crichton
Nis Meinert
Tim Chevalier
YAMAMOTO Takashi
Catherine
Yuta Saito
Timothy McCallum
Masashi Yoshimura
Andrii Rublov
Philip Rying
Brett Cannon
liang.he
Michael Lill
Andrew Brown
Anuraag Agrawal
Ryan Lopopolo
Dan Gohman
Greg. A
gautric
Pat Hickey
Steve Manuel
Sam Clegg
Dan Gohman
Sergey Rubanov