Node 24.8.0 has a regression in VM

[alexander-akait]

Version

24.8.0

Platform

Linux laptop 6.14.0-29-generic #29~24.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Aug 14 16:52:50 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

But not related to the problem, any platform

Subsystem

No response

What steps will reproduce the bug?

Investigating, works fine with 24.7.0

Now:

Module status must be unlinked

Ref - webpack/webpack#19901

How often does it reproduce? Is there a required condition?

Always

What is the expected behavior? Why is that the expected behavior?

Works without any errors

What do you see instead?

Error with Module status must be unlinked

Additional information

I think #59000 create a regression

[targos]

@legendecas

[alexander-akait]

Found reproducible test example:

const vm = require("vm");

(async () => {
	const module = new vm.SourceTextModule("console.log('Works')", {
		initializeImportMeta(meta) {
			// Note: this object is created in the top context. As such,
			// Object.getPrototypeOf(import.meta.prop) points to the
			// Object.prototype in the top context rather than that in
			// the contextified object.
			meta.prop = {};
		}
	});
    // Works fine with 24.7.0, broken with 24.8.0
	if (module.instantiate) module.instantiate();
	await module.link(() => {});
	await module.evaluate();
})();

Not sure if this is expected or not? I known instantiate is not in official API, but we have tests cases from node v10 to v24 and this code works before

[joyeecheung]

Do you know why you were calling instantiate()? It's not an API until it was added in 24.8.0 #59000 - before that it was not undocumented, but just non-existent and therefore never called; now that there's a new API that's happened to be named instantiate(), the code is invoking it which it shouldn't (because link() already does instantiation. In the new API design, you either use linkRequests() + instantiate() which allows you to do it in two different steps, or you use link() that does things in one step).

[joyeecheung]

It seems there was a different instantiate() method that existed during v10-v12.11.0 until removed by #29776 , and then in v24.8.0, a new but different instantiate() was added; I think for your use case, you can either

1. change if (module.instantiate) to if (module.instantiate && process.version < "v13") (or other more robust way to check that it's the instantiate() method below 13)
2. just remove that instantiate() branch if you are not particularly interested in supporting this use case for Node.js v10-v12.11.0 in 2025.

[legendecas]

It seems like webpack is still running tests against Node.js v10.x: https://github.com/webpack/webpack/actions/runs/17681438488/job/50256443191?pr=19901. I'd agree with Joyee that this will need a version guard to continue use the already removed experimental behavior.

[legendecas]

As explained in #59866 (comment), this is not a regression that needs a fix in Node.js. Feel free to re-open if you think this is not the case.