diff --git a/Rakefile.cross b/Rakefile.cross
index 7035ef82f786ac2318411d70d4e4c227d55099bc..8721f4d220c7abbf05cc8aeb8e204789373e8a66 100644
--- a/Rakefile.cross
+++ b/Rakefile.cross
@@ -121,7 +121,7 @@ LIBZ_ENV = [
 ]
 
 # generate the makefile in a clean build location
-task LIBZ_MAKEFILE => [STATIC_LIBZ_BUILDDIR] do |t|
+file LIBZ_MAKEFILE => [STATIC_LIBZ_BUILDDIR] do |t|
   Dir.chdir( STATIC_LIBZ_BUILDDIR ) do
     options = [
       "--prefix=#{STATIC_INSTALLDIR}",