This was fixed by... commit aa8c2dcb5a098416ce30bf30f65ded786b2f7b65 Author: Shlomi Fish <shlomif@shlomifish.org> Date: Sat Aug 10 10:21:16 2013 +0300 Fix RT #41461 (with a test). A problem with the perl debugger of writing to an undef $LINEINFO. Bump $VERSION to 1.42. For: RT #41461 :040000 040000 796a3b25bf90eca28c38c219b61fd710e699a5fd dc2a7ca390c23dcd215adf0c8d4e76e14b18cf96 M lib --- via perlbug: queue: perl5 status: open https://rt.perl.org/Ticket/Display.html?id=34489