Joseph Ferano
8e074bf0e2
wasm32-wasi needs a sysroot clang does not know about and a builtins archive Fedora does not ship, and both have to reach the C compiles as well as the link — flan_rt.c includes <stdio.h> and never got past it. The flags are computed once and the whole list, not just the triple, is in the object cache key: repointing a sysroot must not be served a stale .o. Fedora ships no wasm libclang_rt.builtins.a and clang's resource directory is root-owned, so a shadow one is built under the object cache with the archive under the name clang looks for. The archive substituted is emscripten's libcompiler_rt.a, a different triple built by a different clang; wasi-sdk is the proper article and the comment says so, because a session reading "wasm32 works" should know which joint is glued. Nothing found means a refusal naming every path tried. The entry point is the other thing no triple tells you: wasi-libc calls __main_argc_argv, the .ll says @main, and the mismatch links clean and then traps on a weak stub. Two lines of C bridge it, and the asm label in them is why the shim is not an infinite self-call. --dev and Build.shared are refused for the target rather than half-supported: both are dlopen, which wasm32 has no equivalent of.
