\[\alpha \gt -1 \land \beta \gt -1 \land i \gt 1\]

\[\frac{\left(\frac{\left(\left(i \cdot \left(\left(\alpha + \beta\right) + i\right)\right) \cdot \left(\left(\beta \cdot \alpha\right) + \left(i \cdot \left(\left(\alpha + \beta\right) + i\right)\right)\right)\right)}{\left(\left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right) \cdot \left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right)\right)}\right)}{\left(\left(\left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right) \cdot \left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right)\right) - 1\right)}\]

\frac{\left(\frac{\left(\left(i \cdot \left(\left(\alpha + \beta\right) + i\right)\right) \cdot \left(\left(\beta \cdot \alpha\right) + \left(i \cdot \left(\left(\alpha + \beta\right) + i\right)\right)\right)\right)}{\left(\left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right) \cdot \left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right)\right)}\right)}{\left(\left(\left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right) \cdot \left(\left(\alpha + \beta\right) + \left(2 \cdot i\right)\right)\right) - 1\right)}

double f(double alpha, double beta, double i) {
        double r5177274 = i;
        double r5177275 = alpha;
        double r5177276 = beta;
        double r5177277 = r5177275 + r5177276;
        double r5177278 = r5177277 + r5177274;
        double r5177279 = r5177274 * r5177278;
        double r5177280 = r5177276 * r5177275;
        double r5177281 = r5177280 + r5177279;
        double r5177282 = r5177279 * r5177281;
        double r5177283 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r5177284 = r5177283 * r5177274;
        double r5177285 = r5177277 + r5177284;
        double r5177286 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r5177287 = r5177286 * r5177274;
        double r5177288 = r5177277 + r5177287;
        double r5177289 = r5177285 * r5177288;
        double r5177290 = r5177282 / r5177289;
        double r5177291 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r5177292 = r5177291 * r5177274;
        double r5177293 = r5177277 + r5177292;
        double r5177294 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r5177295 = r5177294 * r5177274;
        double r5177296 = r5177277 + r5177295;
        double r5177297 = r5177293 * r5177296;
        double r5177298 = /* ERROR: no support for value #<cpointer:posit16> in C */;
        double r5177299 = r5177297 - r5177298;
        double r5177300 = r5177290 / r5177299;
        return r5177300;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 0 
(FPCore (alpha beta i)
  :name "Octave 3.8, jcobi/4"
  :pre (and (>.p16 alpha #<cpointer:posit16>) (>.p16 beta #<cpointer:posit16>) (>.p16 i #<cpointer:posit16>))
  (/.p16 (/.p16 (*.p16 (*.p16 i (+.p16 (+.p16 alpha beta) i)) (+.p16 (*.p16 beta alpha) (*.p16 i (+.p16 (+.p16 alpha beta) i)))) (*.p16 (+.p16 (+.p16 alpha beta) (*.p16 #<cpointer:posit16> i)) (+.p16 (+.p16 alpha beta) (*.p16 #<cpointer:posit16> i)))) (-.p16 (*.p16 (+.p16 (+.p16 alpha beta) (*.p16 #<cpointer:posit16> i)) (+.p16 (+.p16 alpha beta) (*.p16 #<cpointer:posit16> i))) #<cpointer:posit16>)))

Backtrace

hash-ref: no value found for key key: '(#<cpointer:posit16> #<cpointer:posit16> #<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-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