Allow specifying certain types we shouldn't derive/impl Hash for

[fitzgen]

Add --no-hash <regex> and Builder::no_hash(String) to supply regexes for matching against types that we should not derive or implement Hash for.

Adding this feature involves:

• Adding a new RegexSet member to bindgen::Builder (similar to the whitelisted_types set).

• A Builder method to add strings to that RegexSet.

• Plumbing in src/options.rs to convert --no-hash <regex> CLI flags into invocations of the builder method.

• Making the MonotoneFramework::constrain function in src/ir/analysis/derive_hash.rs check if the given item is explicitly marked not to be Hash, and if so, inserting it into the self.cannot_derive_hash set via return self.insert(id).

• Tests!

  • When the no-hash type is transitively referenced by a whitelisted item

  • When the no-hash type is explicitly whitelisted

  • When the no-hash type is marked opaque

[treiff]

I'll give this a shot. @highfive: assign me

[highfive]

Hey @treiff! Thanks for your interest in working on this issue. It's now assigned to you!

[fitzgen]

@treiff making any progress here? Anything that I can help with?

[treiff]

Hey @fitzgen, sorry for the delay. I had made a little progress, however I've got a bunch going on with work and don't think I'm actually going to have the time to give this the attention it needs. Probably best you un-assign me.

Thanks for the follow up reminder.

[fitzgen]

No problem!

[ghost]

@highfive: assign me

[highfive]

Hey @seemyvest! Thanks for your interest in working on this issue. It's now assigned to you!

[emilio]

Fixed by #1105