+(macrolet ((define-fasl-format-features ()
+ (let (;; master value for *F-P-A-F-F*
+ (fpaff '(:sb-thread)))
+ `(progn
+ ;; a list of *(SHEBANG-)FEATURES* flags which affect
+ ;; binary compatibility, i.e. which must be the same
+ ;; between the SBCL which compiles the code and the
+ ;; SBCL which executes the code
+ ;;
+ ;; This is a property of SBCL executables in the
+ ;; abstract, not of this particular SBCL executable,
+ ;; so any flag in this list may or may not be present
+ ;; in the *FEATURES* list of this particular build.
+ (defparameter *features-potentially-affecting-fasl-format*
+ ',fpaff)
+ ;; a string representing flags of *F-P-A-F-F* which
+ ;; are in this particular build
+ ;;
+ ;; (A list is the natural logical representation for
+ ;; this, but we represent it as a string because
+ ;; that's physically convenient for writing to and
+ ;; reading from fasl files, and because we don't
+ ;; need to do anything sophisticated with its
+ ;; logical structure, just test it for equality.)
+ (defparameter *features-affecting-fasl-format*
+ ,(let ((*print-pretty* nil))
+ (prin1-to-string
+ (sort
+ (copy-seq
+ (intersection sb-cold:*shebang-features* fpaff))
+ #'string<
+ :key #'symbol-name))))))))
+ (define-fasl-format-features))
+