The following code is allowed by the grammar of Python 3.4, but not Python 3.5:

`def f(): g(*a or b)`

where unary `*` has the lowest precedence, i.e. it is equivalent to:

`def f(): g(*(a or b))`

The cause of the regression that the 3.4 grammar for `arglist` uses `'*' test` but the 3.5 grammar uses `'*' expr`. This is likely an oversight due to the PEP 448 changes; the fix should most likely be applied to the new `display`s as well as fixing the regression.


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Thanks to zware on IRC for actually testing this for me, since I don't have a runnable python3.5, just docs.