build: Speed up .go compilation.

* build-aux/compile-all.scm: New file.
* Makefile.am (EXTRA_DIST): Add it.
(%.go, make-go): New rules.

1 files changed, 82 insertions, 0 deletions

diff --git a/build-aux/compile-all.scm b/build-aux/compile-all.scm
new file mode 100644
index 0000000000..e0877dbe8c
--- /dev/null
+++ b/build-aux/compile-all.scm
@@ -0,0 +1,82 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016 Taylan Ulrich Bayırlı/Kammer <taylanbayirli@gmail.com>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(use-modules (system base target)
+             (ice-9 match)
+             (ice-9 threads)
+             (guix build utils))
+
+(define compile-options '(format unbound-variable arity-mismatch))
+
+(define host (getenv "host"))
+
+(define srcdir (getenv "srcdir"))
+
+(define (relative-file file)
+  (if (string-prefix? (string-append srcdir "/") file)
+      (string-drop file (+ 1 (string-length srcdir)))
+      file))
+
+(define (file-mtime<? f1 f2)
+  (< (stat:mtime (stat f1))
+     (stat:mtime (stat f2))))
+
+(define (scm->go file)
+  (let* ((relative (relative-file file))
+         (without-extension (string-drop-right relative 4)))
+    (string-append without-extension ".go")))
+
+(define (file-needs-compilation? file)
+  (let ((go (scm->go file)))
+    (or (not (file-exists? go))
+        (file-mtime<? go file))))
+
+(define (file->module file)
+  (let* ((relative (relative-file file))
+         (module-path (string-drop-right relative 4)))
+    (map string->symbol
+         (string-split module-path #\/))))
+
+;;; To work around <http://bugs.gnu.org/15602> (FIXME), we want to load all
+;;; files to be compiled first.  We do this via resolve-interface so that the
+;;; top-level of each file (module) is only executed once.
+(define (load-module-file file)
+  (let ((module (file->module file)))
+    (format #t "  LOAD     ~a~%" module)
+    (resolve-interface module)))
+
+(define (compile-file* file output-mutex)
+  (let ((go (scm->go file)))
+    (with-mutex output-mutex
+      (format #t "  GUILEC   ~a~%" go)
+      (force-output))
+    (mkdir-p (dirname go))
+    (with-target host
+      (lambda ()
+        (compile-file file
+                      #:output-file go
+                      #:opts compile-options)))))
+
+(match (command-line)
+  ((_ . files)
+   (let ((files (filter file-needs-compilation? files)))
+     (for-each load-module-file files)
+     (let ((mutex (make-mutex)))
+       (par-for-each (lambda (file)
+                       (compile-file* file mutex))
+                     files)))))