Assertion "! WLSTRIDE_ISMODIFIED( stride1)" failed for with-loop with "width"

The compiler reports a failed assertion when trying to compile the following code from Listing 31 from the tutorial.

use StdIO: all;
use Array: all;

int main()
{
  a = with {
        (. <= [i,j] <= . step [2,4] width [1,2]): 42;
      }: genarray([5,6], 0);
  print(a);

  return 0;
}

Command: sac2c -check tc main.sac Output:

warning: Option -check c implies option -ecc.
warning: Insertion of explicit conformity checks has been enabled.
Internal compiler error
Assertion "! WLSTRIDE_ISMODIFIED( stride1)" failed at /var/jenkins/workspace/sac2c-packages/cudas/cuda-8.0/label/RHEL7/packs/RPM/phmo/ON/src/libsac2c/wltransform/wltransform.c:3849 -- stride was modified
Please file a bug at: http://bugs.sac-home.org

sac2c -V:

sac2c 1.2-beta-BlackForest-467-gce8d4
build-type: RELEASE
built-by: "builder" at 2017-04-24T21:49:30

StdLib version: 1.3REV2-1 (from AUR package)

uname -or: 4.19.69-1-MANJARO GNU/Linux