* If a function prototype is declarated inside a function, do not
translate it to a top-level extern function declaration. Similar to
extern local variable, just wrapped it into a block-local struct.
* Add a new extern_local_fn tag of aro_translate_c node for present
extern local function declaration.
* When a function body has a C function prototype declaration, it adds
an extern local function declaration. Subsequent function references
will look for this function declaration.
`wasm2c` uses an interesting mechanism to "fake" the existence of cache
directories. However, `wasi_snapshot_preview1_fd_seek` was not correctly
integrated with this system, so previously crashed when run on a file in
a cache directory due to trying to call `fseek` on a `FILE *` which was
`NULL`.
* When saving bigint limbs, we gave the iovec the wrong length, meaning
bigint data (and the following string and compile error data) was corrupted.
* When updating a stale ZOIR cache, we failed to truncate the file, so
just wrote more bytes onto the end of the stale cache.
This is actually completely well-defined. The resulting slice always has
0 elements. The only disallowed case is casting *to* a slice of a
zero-bit type, because in that case, you cna't figure out how many
destination elements to use (and there's *no* valid destination length
if the source slice corresponds to more than 0 bits).
This change fixes false-positive cache hits for run steps that get run
with different sets of environment variables due the the environment map
being excluded from the cache hash.
The "musl" part of the Zig target triples `wasm32-wasi-musl` and
`wasm32-emscripten-musl` refers to the libc, not really the ABI.
For WASM, most LLVM-based tooling uses `wasm32-wasi`, which is
normalized into `wasm32-unknown-wasi`, with an implicit `-unknown` and
without `-musl`.
Similarly, Emscripten uses `wasm32-unknown-emscripten` without `-musl`.
By using `-unknown` instead of `-musl` we get better compatibility with
external tooling.
While it is not allowed for a function coercion to change whether a
function is generic, it *is* okay to make existing concrete parameters
of a generic function also generic, or vice versa. Either of these cases
implies that the result is a generic function, so comptime type checks
will happen when the function is ultimately called.
Resolves: #21099
