Fix miri error in into_inner() of CString

[Stargateur]

Fix #62553

I choice to not transmute because I think it's more unsafe and in case the structure change this code should always work.

r? @RalfJung

[rust-highfive]

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[Stargateur]

I would like to add a test but I don't know how.

[RalfJung]

Thanks a lot! I prefer the ManuallyDrop version as well. :)

I would like to add a test but I don't know how.

You mean a test that this does not error in Miri any more? For that, please make a PR at https://github.com/rust-lang/miri/.

[RalfJung]

This looks great! When you force-push and want a new review, please leave a note saying so; GitHub unfortunately does not send email notifications for force-pushes.

@bors r+

Do you want to try to add a Miri test case as well? Do you need mentoring for that?

[bors]

📌 Commit 4c4bd34 has been approved by RalfJung

[bors]

⌛ Testing commit 4c4bd34 with merge 85a360e...

[bors]

☀️ Test successful - checks-azure, checks-travis, status-appveyor
Approved by: RalfJung
Pushing 85a360e to master...