Failing assertions in indxpath.c, placeholder.c and brin_minmax.c

Hi,

when running my random query generator contraption[1] against the
regression database of 9.5 or master, it occasionally triggers one of
the following three assertions.  Someone more knowledgeable might want
to take a look at them...

-- FailedAssertion("!(outer_rel->rows > 0)", File: "indxpath.c", Line: 1911)
-- sample query:   select     rel1925354.loid as c0,     rel1925353.version as c1   from     (select
rel1925352.aaas c0,           rel1925352.aa as c1         from           public.b as rel1925352         where
(rel1925352.bbis NULL)           and (rel1925352.bb < rel1925352.bb)) as subq_303136         inner join
pg_catalog.pg_stat_sslas rel1925353         on (subq_303136.c0 = rel1925353.pid )       right join
pg_catalog.pg_largeobjectas rel1925354       on (subq_303136.c0 = rel1925354.pageno )   where (rel1925353.clientdn !~
rel1925353.clientdn)    and (rel1925353.cipher <= rel1925353.clientdn);
 

,----[ git bisect ]
|   first bad commit: [3f8c23c4d31d4a0e801041733deb2c7cfa577b32] Improve
|   predtest.c's ability to reason about operator expressions.
`----

-- FailedAssertion("!(!bms_is_empty(phinfo->ph_eval_at))", File: "placeholder.c", Line: 109)
-- sample query:   select     rel1600276.viewowner as c0,     rel1600274.maxwritten_clean as c1,
rel1600275.n_tup_hot_updas c2   from     pg_catalog.pg_stat_bgwriter as rel1600274         inner join
pg_catalog.pg_stat_xact_all_tablesas rel1600275         on (rel1600274.maxwritten_clean = rel1600275.seq_scan )
rightjoin pg_catalog.pg_views as rel1600276         right join pg_catalog.pg_operator as rel1600277         on
(rel1600276.viewname= rel1600277.oprname )       on (rel1600275.relname = rel1600277.oprname )   where 3 is not NULL;
 

,----[ git bisect ]
|   first bad commit: [f4abd0241de20d5d6a79b84992b9e88603d44134] Support
|   flattening of empty-FROM subqueries and one-row VALUES tables.
`----

-- FailedAssertion("!(key->sk_flags & 0x0080)", File: "brin_minmax.c", Line: 177)
-- sample query:   select     rel167978.namecol as c0   from     information_schema.parameters as rel167972       left
joinpublic.student as rel167977         inner join public.brintest as rel167978         on (rel167977.age =
rel167978.int4col)       on (rel167972.interval_precision = rel167977.age )   where rel167977.name <> rel167977.name;
 

regards,
andreas

Footnotes: 
[1]  https://github.com/anse1/sqlsmith