@ai-ecoverse/wasm-clang

Clang/LLD 24 for the slicc wasm realm. Relinked with current libslicc (Module.sliccKernel spawn) + ENVIRONMENT=web,worker,node.

Companions:

• @ai-ecoverse/wasix-sysroot (WASIXCC_SYSROOT_PREFIX)
• @ai-ecoverse/wasm-binaryen (wasm-opt for fork Asyncify — on PATH)

Drivers

cc / gcc / c++ / g++ / wasixcc / wasix++ are #!/bin/sh scripts (slicc.commands { "script": "bin/…" }). Use them as the normal compilers — no extra WASI/EH flags needed for typical builds.

• Target: --target=wasm32-wasip1 (sysroot ships a real lib/wasm32-wasip1).
• C++ links -lc++ -lc++abi -lunwind (exnref exceptions, threads, iostream).
• Output is a WASI program SLICC runs directly (no separate host wrapper).
• Executable link that imports proc_fork / stack_checkpoint runs wasm-opt --asyncify (from @ai-ecoverse/wasm-binaryen) automatically so fork works on the SLICC host. Plain programs skip asyncify.
• -shared: side module, -nostdlib (no libc) — resolve symbols against a PIE main that exports them.
• PIE / dlopen main: cc -rdynamic … or cc -fPIC foo.c -o foo (no -shared) → -pie --export-all, libc whole-archive, tag stubs. Then dlopen("./libsq.so") works.
• CMake: CC=cc CXX=c++ cmake … — Clang 24 is identified; pthread.h and the sysroot resolve under SLICC.

One module for every tool

bin/llvm.wasm holds clang, lld, llvm-ar, llvm-nm, llvm-objcopy and llvm-symbolizer, linked together so they share one copy of LLVM; the tool is chosen by its name (argv[0]), or llvm <tool> args…. bin/ ships a glue file under every name emcc constructs under LLVM_ROOT (clang, clang++, lld, wasm-ld, ld.lld, llvm-ar, llvm-ranlib, llvm-nm, llvm-objcopy, llvm-strip, llvm-symbolizer): each is a byte-copy of bin/llvm, which locates llvm.wasm beside it. slicc.commands covers the same names plus ar, ranlib, nm, strip for PATH lookups.

Not shipped (emcc only needs these for -g / split-dwarf / coverage / emsize / sourcemap demangle): llvm-dwarfdump, llvm-dwp, clang-scan-deps, llvm-profdata, llvm-cov, llvm-size, llvm-cxxfilt.

cc hello.c -o hello
cc -fPIC -shared sq.c -o libsq.so
cc -rdynamic -fPIC dl.c -o dl   # PIE main exporting libc for dlopen
c++ -O2 t.cpp -o t              # iostream + exceptions + threads

CC=cc CXX=c++ cmake -S . -B build
cmake --build build