SQLite

The following query results in an assertion fault (debug mode) or a 
segfault (when compiled as for delivery):

~~~~~
WITH
  cst(rsx, rsy) AS  (
    SELECT 100, 100
  ),
  cst2(minx, maxx, stepx, miny, maxy, stepy, qualitativex, qualitativey) AS (    
    SELECT NULL, NULL, NULL, NULL, NULL, NULL, 0, 0
  ),
  ds0(m, n, x, y, x2, y2, title, size, mark, label, markmode) AS (
    SELECT 1, 2, 3, 4, 5, 6, 7 , 8, 9, 10, 11
  ),
  ds(m, n, x, y, x2, y2, title, size, mark, label, markmode) AS (
    SELECT m, n, x,
      y, x2,
      y2,
      title, size, mark, label, markmode
    FROM ds0
    WINDOW w AS (PARTITION BY m, x ORDER BY n)
  ),
  d(m, n, x, y, x2, y2, labelx,labely,title,size,mark,label,markmode) AS (
    SELECT m, n, x, y,  x2, y2, x, y, title, size, mark, label, markmode
    FROM ds, cst2
  ),
  ylabels(y, label) AS (
    SELECT y, MIN(labely) FROM d GROUP BY y
  ),
  yaxis(maxy, miny, stepy , minstepy) AS (
    WITH
      xt0(minx, maxx) AS (
        SELECT  coalesce(miny, min(min(y2),
                                             min(y))),
                                    coalesce(maxy, max(max(y2),
                                             max(y))) + qualitativey
                              FROM d, cst2
      ),
      xt1(mx, mn) AS (SELECT maxx, minx FROM xt0),
      xt2(mx, mn, step) AS (SELECT mx, mn, (mx-mn)  FROM xt1),
      
      xt3(mx, mn, ms) AS (
        SELECT mx, mn, first_value(rs) OVER (order by x desc) AS ms
          FROM (SELECT mx, mn, step, f,(mx-mn) as rng,
                       1.0*step/f as rs, 1.0*(mx-mn)/(step/f) AS x
                  FROM xt2, (SELECT 1 AS f UNION ALL SELECT 2
                              UNION ALL SELECT 4
                              UNION ALL SELECT 5)) AS src
                 WHERE x < 10 limit 1),
      xt4(minstepy) AS (
        SELECT MIN(abs(y2-y)) FROM d WHERE y2 != y
      )
    SELECT (mx/ms)*ms, (mn/ms)*ms, coalesce(stepy, ms),
                   coalesce(minstepy, ms, stepy)  FROM xt3, cst2,xt4
  ),
  distinct_mark_n_m(mark, ze, zem, title) AS (
    SELECT DISTINCT mark, n AS ze, m AS zem, title FROM ds0
  ),
  facet0(m, mi, title, radial) AS (
    SELECT md, row_number() OVER () - 1, title, 'radial'
                    IN (SELECT mark FROM distinct_mark_n_m WHERE zem = md)
    FROM (SELECT DISTINCT zem AS md, title AS title
                     FROM distinct_mark_n_m ORDER BY 2, 1)
  ),
  facet(m, mi, xorigin, yorigin, title, radial) AS (
    SELECT m, mi,
      rsx * 1.2 * IFNULL(CASE WHEN (
        0
      ) > 0 THEN mi / (
        0
      ) ELSE mi % (
        2
      )  END, mi),
      rsy  * 1.2 * IFNULL(CASE WHEN (
        2
      ) > 0 THEN mi / (
        2
      ) ELSE mi / (
        0
      )  END, 0),
      title, radial FROM facet0, cst
  ),
  radygrid(m, mi, tty, wty, ttx, ttx2, xorigin, yorigin) AS (
    SELECT m, mi,  rsy / 2 / ((maxy-miny)/stepy) * (value-1) AS tty,
           coalesce(NULL, miny + stepy * (value-1)) AS wty,
           xorigin, xorigin+rsx, xorigin + rsx / 2,
           yorigin + rsy / 2
      FROM generate_series(1), yaxis, cst,
           facet LEFT JOIN ylabels ON ylabels.y = (miny + (value-1) * stepy)
     WHERE radial AND stop = 1+1.0*(maxy-miny)/stepy
  ),
  ypos(m, mi, pcx, pcy, radial) AS (
    SELECT m, mi, xorigin, yorigin + CASE
      WHEN 0 BETWEEN miny AND maxy THEN
        rsy - (0 - miny) * rsy / (maxy-miny)
      WHEN 0 >= maxy THEN 0
      ELSE  rsy
    END, radial FROM yaxis, cst, facet WHERE NOT radial
    UNION ALL
    SELECT m, mi, xorigin + rsx / 2, yorigin + (CASE
      WHEN 0 BETWEEN miny AND maxy THEN
        rsy - (0 - miny) * rsy / 2 / (maxy-miny)
      WHEN 0 >= maxy THEN 0
      ELSE  rsy
    END ) / 2, radial FROM yaxis, cst, facet WHERE radial
  )
SELECT * FROM radygrid , ypos;
~~~~~

This problem was reported by [Forum post a41295d743][1].  Bisecting
suggests the problem originated at [check-in b5a0778cc5a98a86](b5a0778cc5a98a86),
the implementation of the MATERIALIZED and NOT MATERIALIZED hints.

[1]: https://sqlite.org/forum/forumpost/a41295d743

Simplified test case:

> ~~~
WITH xyz(a) AS (
  WITH abc AS ( SELECT 1234 ) SELECT * FROM abc
)
SELECT * FROM xyz AS one, xyz AS two, (
  SELECT * FROM xyz UNION ALL SELECT * FROM xyz
);
~~~