Check that shims are called with the correct number of arguments

[ghost]

Fixes #1272

Some shims don't use all their arguments, I've assumed they are being called in tests with the correct number of arguments here.

[bors]

☔ The latest upstream changes (presumably #1299) made this pull request unmergeable. Please resolve the merge conflicts.

[RalfJung]

Hi @toc-the-younger, welcome and thank you so much for your first PR here!
I'll add reviewing this to my queue, but as you can see there are some older PRs I have to get to first, so please don't be worried when it takes a bit for me tog et back to you.

[bors]

☔ The latest upstream changes (presumably #1324) made this pull request unmergeable. Please resolve the merge conflicts.

[eddyb]

In case it got lost, I left a comment a few days ago: #1298 (comment).

[bors]

☔ The latest upstream changes (presumably #1284) made this pull request unmergeable. Please resolve the merge conflicts.

[RalfJung]

Could you add a testcase for some intrinsic and some foreign item that we call with too few / too many arguments? (There's no point in testing all of them, but we should at least cover one, I think.)

[RalfJung]

Also please rebase, we prefer not to have merge conflicts in PRs.

[RalfJung]

#1390 added a new shim which also needs to be added here.

[RalfJung]

This looks great, thanks a lot. :-)
@bors r+

[bors]

📌 Commit f741f2c has been approved by RalfJung

[bors]

⌛ Testing commit f741f2c with merge 2f974f6...

[bors]

☀️ Test successful - checks-travis, status-appveyor
Approved by: RalfJung
Pushing 2f974f6 to master...