How about an explanation, as indicated in the original message?
The answer "it's a bug", as indicated in the first reply isn't good enough? If you want details of what caused the bug, get a git clone of the perl source, and run 'git-bisect' between 5.6.0 and 5.6.1 to see which commit first triggers the unwanted behaviour.

In reply to Re^3: tr funkiness in 5.6.[12] (but not 5.6.0!) by JavaFan
in thread tr funkiness in 5.6.[12] (but not 5.6.0!) by belg4mit

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