segfault in badly typed pattern match

[robertylewis]

This was found in class today by Joseph Rotella:

def f : ∀ (α : Type), list α → unit
| α [] := ()
| α ((y::ys)::xs) := ()

crashes the server. I don't have a debug version of Lean handy to see if/where there are assertion violations.

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Description

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Versions

Replicated in 3.30 and 3.33.

Additional Information

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