Expose `ScriptCompiler::CachedDataVersionTag`

[zertosh]

I'm using V8's code cache as exposed by vm in https://github.com/zertosh/v8-compile-cache, but I'm hitting cache versioning issues. I'd like know with certainty that a particular cache generated by one machine is compatible with another. ScriptCompiler::CachedDataVersionTag can let you do that (

node/deps/v8/include/v8.h

Lines 1379 to 1397 in ca48071

	/**
	* Return a version tag for CachedData for the current V8 version & flags.
	*
	* This value is meant only for determining whether a previously generated
	* CachedData instance is still valid; the tag has no other meaing.
	*
	* Background: The data carried by CachedData may depend on the exact
	* V8 version number or currently compiler flags. This means when
	* persisting CachedData, the embedder must take care to not pass in
	* data from another V8 version, or the same version with different
	* features enabled.
	*
	* The easiest way to do so is to clear the embedder's cache on any
	* such change.
	*
	* Alternatively, this tag can be stored alongside the cached data and
	* compared when it is being used.
	*/
	static uint32_t CachedDataVersionTag();

).

I'd like to submit a PR exposing that data somewhere. Maybe expose it as a function on the vm module, or a static function on the Script constructor. Any ideas? Preferences?

[addaleax]

I'd like to submit a PR exposing that data somewhere.

Go for it! Let us know if there’s anything you need.

Maybe expose it as a function on the vm module, or a static function on the Script constructor. Any ideas? Preferences?

My first instinct would be the latter, but that might just be something that needs to be settled during PR review.

[addaleax]

#11515 has been merged, so it looks like we’re good here and this can be closed. Thanks again for taking care of this!