wasi-libc fails to link --target=wasm32-wasip1 with undefined symbol: __muloti4

hello everyone,

I used to bootstrap a wasm32-wasi toolchain for llvm-18, llvm-19, llvm-20 and llvm-21 without any issues. llvm-22 started to ask for wasm32-wasip1, but this fails:

llvm-ar --format=gnu crs build/wasm32-wasip1/libc.so.a build/wasm32-wasip1/libc-top-half/musl/src/time/wcsftime.pic.o build/wasm32-wasip1/libc-top-half/musl/src/unistd/gethostname.pic.o build/wasm32-wasip1/libc-top-half/musl/src/unistd/posix_close.pic.o build/wasm32-wasip1/libc-top-half/sources/arc4random.pic.o build/wasm32-wasip1/thread-stub/pthread_barrier_destroy.pic.o build/wasm32-wasip1/thread-stub/pthread_barrier_init.pic.o build/wasm32-wasip1/thread-stub/pthread_barrier_wait.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_broadcast.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_destroy.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_init.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_signal.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_timedwait.pic.o build/wasm32-wasip1/thread-stub/pthread_cond_wait.pic.o build/wasm32-wasip1/thread-stub/pthread_create.pic.o build/wasm32-wasip1/thread-stub/pthread_detach.pic.o build/wasm32-wasip1/thread-stub/pthread_join.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_consistent.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_getprioceiling.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_lock.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_timedlock.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_trylock.pic.o build/wasm32-wasip1/thread-stub/pthread_mutex_unlock.pic.o build/wasm32-wasip1/thread-stub/pthread_once.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_rdlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_timedrdlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_timedwrlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_tryrdlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_trywrlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_unlock.pic.o build/wasm32-wasip1/thread-stub/pthread_rwlock_wrlock.pic.o build/wasm32-wasip1/thread-stub/pthread_spin_lock.pic.o build/wasm32-wasip1/thread-stub/pthread_spin_trylock.pic.o build/wasm32-wasip1/thread-stub/pthread_spin_unlock.pic.o
clang --target=wasm32-wasip1 -nodefaultlibs \
-shared --sysroot=/var/tmp/portage/cross_llvm-wasm32-wasip1/wasi-libc-0_pre20251218/work/wasi-libc-0_pre20251218/sysroot \
-o /var/tmp/portage/cross_llvm-wasm32-wasip1/wasi-libc-0_pre20251218/work/wasi-libc-0_pre20251218/sysroot/lib/wasm32-wasip1/libc.so -Wl,--whole-archive build/wasm32-wasip1/libc.so.a -Wl,--no-whole-archive \
-Wl,--allow-undefined-file=linker-provided-symbols.txt \
build/wasm32-wasip1/resource-dir//lib/wasm32-unknown-wasip1/libclang_rt.builtins.a \
-O2 -DNDEBUG 
wasm-ld: warning: creating shared libraries, with -shared, is not yet stable
wasm-ld: error: build/wasm32-wasip1/libc.so.a(pselect.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(futimens.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(futimens.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(utimensat.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(utimensat.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(clock_nanosleep.pic.o): undefined symbol: __muloti4
wasm-ld: error: build/wasm32-wasip1/libc.so.a(cacosl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __addtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __multf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __multf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __multf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(casinl.pic.o): undefined symbol: __addtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(catanl.pic.o): undefined symbol: __multf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(catanl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(catanl.pic.o): undefined symbol: __multf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(catanl.pic.o): undefined symbol: __subtf3
wasm-ld: error: build/wasm32-wasip1/libc.so.a(catanl.pic.o): undefined symbol: __addtf3
wasm-ld: error: too many errors emitted, stopping now (use -error-limit=0 to see all errors)
clang: error: linker command failed with exit code 1 (use -v to see invocation)

the full build log: build.log.gz

this is an amd64 machine, gcc-14.3.0, clang-22.1.0_rc1

Start by reproducing the reported clang --target=wasm32-wasip1 link command using the objects in build/wasm32-wasip1 and the referenced libclang_rt.builtins.a. Inspect build.log.gz and linker-provided-symbols.txt to trace the missing runtime symbols. Done means the libc.so link completes without the reported undefined symbols.