WASIX test revamp

[zebreus]

Description

[Copilot]

Pull request overview

This PR revamps the WASIX test infrastructure by introducing a new test utility framework and comprehensive context switching tests. The changes replace the old inline test compilation approach with a more structured system using build scripts and test utilities.

Changes:

• Added wasixcc_test_utils.rs providing utilities for compiling and running WASIX tests
• Refactored context_switching.rs to use the new build script-based test approach
• Added 19 new context switching test cases with corresponding C source files and build scripts
• Updated .gitignore to exclude build artifacts while preserving source files

Reviewed changes

Copilot reviewed 57 out of 76 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
lib/wasix/tests/wasixcc_test_utils.rs	New test utility framework with compilation and execution helpers
lib/wasix/tests/context_switching.rs	Refactored to use build scripts instead of inline compilation
lib/wasix/tests/.gitignore	Updated patterns for new test structure
lib/wasix/tests/context_switching/*/build.sh	Simple build scripts for each test case
lib/wasix/tests/context_switching//.c	Comprehensive test cases for context switching scenarios

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[marxin]

When running locally, I noticed a couple of failing tests due to:

  stderr ───
    Build stdout:
    Build stderr: main.c:2:10: fatal error: 'ffi.h' file not found
        2 | #include <ffi.h>
          |          ^~~~~~~
    1 error generated.
    Error: Command failed with status: exit status: 1; the command was: "/home/marxin/.wasixcc/llvm/bin/clang" "--sysroot" "/home/marxin/.wasixcc/sysroot/sysroot-exnref-ehpic" "--target=wasm32-wasi" "-c" "-matomics" "-mbulk-memory" "-mmutable-globals" "-pthread" "-mthread-model" "posix" "-fno-trapping-math" "-D_WASI_EMULATED_MMAN" "-D_WASI_EMULATED_SIGNAL" "-D_WASI_EMULATED_PROCESS_CLOCKS" "-fwasm-exceptions" "-mllvm" "--wasm-enable-eh" "-mllvm" "--wasm-enable-sjlj" "-mllvm" "--wasm-use-legacy-eh=false" "-fPIC" "-ftls-model=global-dynamic" "-fvisibility=default" "-fPIC" "-I/home/marxin/.wasixcc/sysroot/usr/local/include" "-iwithsysroot" "/usr/local/include/c++/v1" "-c" "main.c" "-o" "main.o"

What am I missing?

[zebreus]

@marxin You are missing the compatible sysroot (which means a sysroot with libffi)

[marxin]

@marxin You are missing the compatible sysroot (which means a sysroot with libffi)

❯ l ~/.wasixcc/sysroot/
Permissions Size User   Date Modified Name
drwxr-xr-x     - marxin 26 Feb 09:23   sysroot
drwxr-xr-x     - marxin 26 Feb 09:23   sysroot-eh
drwxr-xr-x     - marxin 26 Feb 09:23   sysroot-ehpic
drwxr-xr-x     - marxin 26 Feb 09:23   sysroot-exnref-eh
drwxr-xr-x     - marxin 26 Feb 09:23   sysroot-exnref-ehpic

How should I install it?

[marxin]

@zebreus cool! Your testing effort exposed a Cranelift EH defect: #6244. I am going to disable the test for now so that it does not block your PR effort.

[marxin]

For the newly added file, please run clang-format so that we have a unified coding style (and we'll get rid of trailing spaces).

I will do that in a subsequent PR, seems there are other files (outside of this PR) that need it as well.

[marxin]

Would be nice if we could get rid of tests/wasix/test.sh and port all the tests in the sub-folder to the new infrastructure.

[zebreus]

@marxin I think it's a good idea to commit the new test files already clang-formatted. There is a clang format config to make the output similar to rustfmt at https://gist.github.com/julyfun/8a739e0529818a4a41bf1762e6859fbf which might be nice. Alternatively we could just use the defaults of clang-format

[marxin]

@marxin I think it's a good idea to commit the new test files already clang-formatted.

Great, then please use the default format configuration. I don't care about the style itself at all (I only obey rustfmt), but it would be nice to have an uniform formatting.