fix an ICE on unwrapping a None

[llogiq]

This very likely fixes #8166 though I wasn't able to meaningfully reduce a test case. This line is the only call to unwrap within that function, which was the one in the stack trace that triggered the ICE, so I think we'll be OK.

@hackmad can you pull and build this branch and check if it indeed fixes your problem?

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changelog: Fixed ICE in [unnecessary_cast]

[rust-highfive]

r? @flip1995

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[xFrednet]

LGTM, the fix matches the stack trace. 👍 You can r=me if we get a positive response. I think this change is also worthy of a changelog entry saying something like: Fixed ICE in [`unnecessary_cast`]

[llogiq]

@bors r=xFredNet

[bors]

📌 Commit 23ffa3c has been approved by xFredNet

[bors]

⌛ Testing commit 23ffa3c with merge 547efad...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: xFredNet
Pushing 547efad to master...

[hackmad]

Thank you for such as fast response. I managed to build both fix-8166 and master and run it against my project and it resolves the issue.

[llogiq]

Thank you for the check, @hackmad