\[\left(\frac{1}{\left(\sqrt{x}\right)}\right) - \left(\frac{1}{\left(\sqrt{\left(x + 1\right)}\right)}\right)\]

\left(\frac{1}{\left(\sqrt{x}\right)}\right) - \left(\frac{1}{\left(\sqrt{\left(x + 1\right)}\right)}\right)

double f(double x) {
        double r10119140 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r10119141 = x;
        double r10119142 = sqrt(r10119141);
        double r10119143 = r10119140 / r10119142;
        double r10119144 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r10119145 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r10119146 = r10119141 + r10119145;
        double r10119147 = sqrt(r10119146);
        double r10119148 = r10119144 / r10119147;
        double r10119149 = r10119143 - r10119148;
        return r10119149;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 0 
(FPCore (x)
  :name "2isqrt (example 3.6)"
  (-.p16 (/.p16 #<cpointer:posit16> (sqrt.p16 x)) (/.p16 #<cpointer:posit16> (sqrt.p16 (+.p16 x #<cpointer:posit16>)))))

Backtrace

hash-ref: no value found for key key: '(#<cpointer:posit16>)		L	C
best-and-tied-at-points	/home/p92/nightlies/herbie/optional-posits/src/core/alt-table.rkt	117	0
atab-add-altn	/home/p92/nightlies/herbie/optional-posits/src/core/alt-table.rkt	202	0
for-loop	/home/p92/nightlies/herbie/optional-posits/src/core/alt-table.rkt	56	2
(unnamed)	/opt/racket-7.0/collects/racket/contract/private/arrow-val-first.rkt	388	18
finalize-iter!	/home/p92/nightlies/herbie/optional-posits/src/mainloop.rkt	272	0
run-iter!	/home/p92/nightlies/herbie/optional-posits/src/mainloop.rkt	321	0
for-loop	/home/p92/nightlies/herbie/optional-posits/src/mainloop.rkt	355	4
run-improve43	/home/p92/nightlies/herbie/optional-posits/src/mainloop.rkt	340	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28