Please include this information when filing a bug report:
herbie shell --seed 2019067
(FPCore (x)
:name "2isqrt (example 3.6)"
:herbie-target
(/ 1 (+ (* (+ x 1) (sqrt x)) (* x (sqrt (+ x 1)))))
(- (/ 1 (sqrt x)) (/ 1 (sqrt (+ x 1)))))
| build-list: contract violation expected: exact-nonnegative-integer? given: '(0) | L | C | |
|---|---|---|---|
| build-list | /opt/racket-7.0/collects/racket/private/list.rkt | 296 | 2 |
| debug-print | /data/pavpan/nightlies/herbie/develop/src/debug.rkt | 107 | 0 |
| run-improve43 | /data/pavpan/nightlies/herbie/develop/src/mainloop.rkt | 346 | 0 |
| (unnamed) | /opt/racket-7.0/collects/racket/private/more-scheme.rkt | 261 | 28 |
| run | /opt/racket-7.0/share/pkgs/profile-lib/main.rkt | 39 | 2 |
| profile-thunk16 | /opt/racket-7.0/share/pkgs/profile-lib/main.rkt | 9 | 0 |
| (unnamed) | /opt/racket-7.0/collects/racket/private/more-scheme.rkt | 261 | 28 |