+
+;;; not documented in CMU CL:-(
+;;;
+;;; reverse engineering observations:
+;;; * seems to be set when translating return values
+;;; * seems to enable the translation of (VALUES), which is the
+;;; Lisp idiom for C's return type "void" (which is likely
+;;; why it's set when when translating return values)
+(defvar *values-type-okay* nil)
+
+(defvar *default-c-string-external-format* nil)