WebAssembly.Function.type not on some platforms

[rentallect]

I have some JSPI-enabled WASM constructed with emscripten 3.1.46. Even when the consuming browser has the JSPI feature enabled, there are some platforms that experience exceptions during the WASM instantiation because the emscripten loader code invokes WebAssembly.Function.type and the WebAssembly.Function object doesn't have type.

For example Mac 12.7 has WebAssembly.Function.type, but...

Mac 14.x doesn't.
Newer Windows11 doesn't.
Newer Fedora doesn't.
...maybe more

Can someone explain what I might be missing here, and if there is a way to resolve this (as in, newer emscripten releases might have fixed this)?

[kripken]

@rentallect That sounds like missing browser support. It might be helpful to know which browsers and which versions you see the issue in (that would be more specific than operating system information).

But @brendandahl who added the usage of WebAssembly.Function.type in #20401 might know the answer - from that PR it sounds like there were some changes to the type reflection API and perhaps those haven't reached all browsers yet?

[rentallect]

I'll get you more data (browser versions affected), but the interesting thing is that WebAssembly.Function.type seems to be vanishing from newer/updated platforms. That is, the same WASM which was working on certain platforms suddenly stopped working after users updated their operating systems. WebAssembly.Function is there, but type is now gone.

[rentallect]

I updated my Chrome today. I now have Version 120.0.6099.109 (Official Build) (arm64). Prior to this update, WebAssembly.Function.type was there, but now it's gone in Chromium, and as a result, my WASM will no longer run.

[sbc100]

From the comment it looks like original.type() the new thing and WebAssembly.Function.type is the old thing, but that code expects one or the other to exist.

See

emscripten/src/library_async.js

Lines 457 to 458 in 67774cf

	// TODO: remove `WebAssembly.Function.type` call when the new API is ready on all the testers.
	var type = original.type ? original.type() : WebAssembly.Function.type(original);

However, it looks like 3.1.46 doesn't have that fallback:

emscripten/src/library_async.js

Line 461 in 1960782

var type = WebAssembly.Function.type(original);

So it looks like the solution here is rebuild using a newer version of emscripten that supports the newer shape of this API.

This kind of breakage is, I'm afraid, sometimes unavoidable when using new and experimental APIs like JSPI.

(@brendandahl is my assessment correct here?)

[rentallect]

I'll upgrade to 3.1.51, rebuild everything, and then report back with the results.