Hm... it seems like this might be #126193, fixed by 9e59c36b (at least that's what a bisect says), fix released with Perl v5.24.

In reply to Re^2: Forcing list context. Brackets (with list within) as an unary right-associative operator by haukex
in thread Forcing list context. Brackets (with list within) as an unary right-associative operator by rsFalse

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