Two minor fixes

[chrisseaton]

No description provided.

[chrisseaton]

Needs tests.

[eregon]

For the 3rd issue, a simple repro is:

ruby 3.0.3p157 (2021-11-24 revision 3fb7d2cadc) [x86_64-linux]
1
~ ∴ chruby dev                                                 
~ ∴ ruby -v -rbigdecimal -e 'p BigDecimal.method(:_load).arity'
truffleruby 22.2.0-dev-e2f62b89, like ruby 3.0.3, GraalVM CE Native [x86_64-linux]
-1

[eregon]

@chrisseaton Do you have local changes on this branch (if so please push them)?
I can take care of the tests and the 3rd issue mentioned just above.

[chrisseaton]

No I don't think we wrote anything else did we? There was the change to Paquito, but that was just to work around the BigDecimal arity bug.

[eregon]

OK, I'm happy to integrate these fixes and add tests then.

[eregon]

For the first issue (-Werror in C exts), I created #2664
For the second, #2665
For the third and last one: #2666

[eregon]

All done now, I'll close this and we'll just need to merge those 3 PRs linked above.

[eregon]

All 3 fixes merged now.