utils: Change 'patch-makefile-SHELL' to support ":=" assignments.

Reported by Ricardo Wurmus <ricardo.wurmus@mdc-berlin.de>.

* guix/build/utils.scm (patch-makefile-SHELL): Update regexp to match
  ":=" assignments.

diff --git a/guix/build/utils.scm b/guix/build/utils.scm
index 01ac896..be91fb4 100644 (file)
--- a/guix/build/utils.scm
+++ b/guix/build/utils.scm
@@ -638,7 +638,7 @@ When KEEP-MTIME? is true, the atime/mtime of FILE are kept unchanged."
 
   (let ((st (stat file)))
    (substitute* file
-     (("^ *SHELL[[:blank:]]*=[[:blank:]]*([[:graph:]]*/)([[:graph:]]+)(.*)$"
+     (("^ *SHELL[[:blank:]]*:?=[[:blank:]]*([[:graph:]]*/)([[:graph:]]+)(.*)$"
        _ dir shell args)
       (let* ((old (string-append dir shell))
              (new (or (find-shell shell) old)))