*PRINT-CASE* setting affects compiler

[Mark Evenson]

As ​reported by Dan Corkill:

The compiler is badly affected with *PRINT-CASE* set to :DOWNCASE, seemingly failing to look up internal definitions.

(in-package :cl-user)

(eval-when (:compile-toplevel :load-toplevel :execute)
 (setf *print-case* ':downcase))

(defstruct rec a b)

[ehuelsmann]

This ticket has been fixed. r13274.