The comments don't seem to match the code here.
+ (let* ((tangled-file (concat (file-name-sans-extension file) ".el")) + (file-mtime (file-attribute-modification-time + (file-attributes (file-truename file)))) + (tangled-mtime (file-attribute-modification-time + (file-attributes (file-truename tangled-file))))) + ;; Tangle only if the Elisp file is older than the Org file. + ;; Filesystem may have coarse timestamp resolution (HFS+, FAT) + ;; so no need to update if timestamps are equal and thus + ;; `org-file-newer-than-p' can not be used here. + (unless (and file-mtime + tangled-mtime + (not (time-less-p tangled-mtime file-mtime)))
Although this looks correct, there's no need to go to the work of computing file-mtime in the common case where tangled-mtime is nil.
