gnu: emacs: Add lexical binding cookies.

* gnu/packages/emacs.scm (emacs-minimal)[#:phases]<install-c-source>
<install-site-start>: Add “;; -*- lexical-binding: t; -*-” at the top of the
generated files.
* gnu/packages/aux-files/emacs/comp-integrity.el: Likewise.

gnu/packages/aux-files/emacs/comp-integrity.el

@@ -1,3 +1,4 @@
+;; -*- lexical-binding: t; -*-
 (require 'ert)
 
 (eval-when-compile

gnu/packages/emacs.scm

@@ -387,6 +387,7 @@
                   (lambda ()
                     (display
                      (string-append
+                      ";; -*- lexical-binding: t; -*-\n"
                       "(setq find-function-C-source-directory \"" dest "\")\n\n"
                       "(provide 'guix-emacs-c-source)")))))))
           (add-after 'install 'install-site-start
@@ -413,6 +414,7 @@
                   (lambda ()
                     (display
                      (string-append
+                      ";; -*- lexical-binding: t; -*-\n"
                       "(when (require 'guix-emacs nil t)\n"
                       "  (guix-emacs-autoload-packages 'no-reload)\n"
                       "  (advice-add 'package-load-all-descriptors"
@@ -630,6 +632,8 @@ editor (console only)")
                libx11
                libxft
                libxpm
+               libxrender
+               libxt
                libwebp
                pango
                poppler)))))

guix/build/emacs-build-system.scm

@@ -182,7 +182,7 @@ locations in the store in '.el' files."
            ;; of generation -pkg.el will fail.
            (condition-case
             nil
-            (let ((version (lm-version)))
+            (let ((version (or (lm-header "package-version") (lm-version))))
               ;; raises an error if version is invalid
               (and (version-to-list version) version))
             (error "0.0.0"))