[significant_drop_tightening] Evaluate the return expression of a block

[c410-f3r]

For whatever reason, the return expression of a block is not contained inside the slice of statements and because of that the lint wasn't evaluating things that could potentially block the release of a lock.

pub fn example() -> i32 {
    let mutex = Mutex::new(1);
    let lock = mutex.lock().unwrap();
    let _ = *lock;
    let _ = *lock;
   do_heavy_computation_that_takes_time_and_returns_i32()
}

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changelog: none

[rustbot]

r? @dswij

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[xFrednet]

r? @xFrednet

[xFrednet]

Woops, yeah I missed this in the last review. Blocks are a bit tricky when it comes to this. Thank you, for finding that so quickly and creating a follow-up PR :)

@bors r+

[bors]

📌 Commit 7518969 has been approved by xFrednet

It is now in the queue for this repository.

[bors]

⌛ Testing commit 7518969 with merge 85d4b5a...

[bors]

☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test
Approved by: xFrednet
Pushing 85d4b5a to master...

[c410-f3r]

Thanks @xFrednet