How to debug TypeError: required field "lineno" missing from expr?

[Laura Creighton]

In a message of Mon, 29 Jun 2015 02:14:43 +0100, Mark Lawrence writes:
>Purely as an exercise I've been converting Grant Jenks' pypatt[1] from 
>2.7 to 3.4.  I've managed to sort out most of the required changes by 
>checking on what I can see with an AST pretty printer[2].  So it's 
>rather frustrating to have the compile stage throw the error given in 
>the subject line.

Are you trying to use ast.copy_location recursively somewhere?
http://bugs.python.org/issue3530  Maybe you have found something else
that doesn't work recursively?

Laura