\[\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\left(\left(\sqrt{\pi \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099298181841732002794742584 + \frac{676.5203681218850988443591631948947906494}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.139216722402807135949842631816864014}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531346025876700878143310547}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621405870046146446838974952698}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.50734327868690520801919774385169148445}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.1385710952657201178173096423051902092993}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019571583242346146658263705831 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.505632735149311617592788074479481785772 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)\]
\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\left(\left(\sqrt{\pi \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099298181841732002794742584 + \frac{676.5203681218850988443591631948947906494}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.139216722402807135949842631816864014}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531346025876700878143310547}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621405870046146446838974952698}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.50734327868690520801919774385169148445}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.1385710952657201178173096423051902092993}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019571583242346146658263705831 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.505632735149311617592788074479481785772 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)
double f(double z) {
        double r24224 = atan2(1.0, 0.0);
        double r24225 = z;
        double r24226 = r24224 * r24225;
        double r24227 = sin(r24226);
        double r24228 = r24224 / r24227;
        double r24229 = 2.0;
        double r24230 = r24224 * r24229;
        double r24231 = sqrt(r24230);
        double r24232 = 1.0;
        double r24233 = r24232 - r24225;
        double r24234 = r24233 - r24232;
        double r24235 = 7.0;
        double r24236 = r24234 + r24235;
        double r24237 = 0.5;
        double r24238 = r24236 + r24237;
        double r24239 = r24234 + r24237;
        double r24240 = pow(r24238, r24239);
        double r24241 = r24231 * r24240;
        double r24242 = -r24238;
        double r24243 = exp(r24242);
        double r24244 = r24241 * r24243;
        double r24245 = 0.9999999999998099;
        double r24246 = 676.5203681218851;
        double r24247 = r24234 + r24232;
        double r24248 = r24246 / r24247;
        double r24249 = r24245 + r24248;
        double r24250 = -1259.1392167224028;
        double r24251 = r24234 + r24229;
        double r24252 = r24250 / r24251;
        double r24253 = r24249 + r24252;
        double r24254 = 771.3234287776531;
        double r24255 = 3.0;
        double r24256 = r24234 + r24255;
        double r24257 = r24254 / r24256;
        double r24258 = r24253 + r24257;
        double r24259 = -176.6150291621406;
        double r24260 = 4.0;
        double r24261 = r24234 + r24260;
        double r24262 = r24259 / r24261;
        double r24263 = r24258 + r24262;
        double r24264 = 12.507343278686905;
        double r24265 = 5.0;
        double r24266 = r24234 + r24265;
        double r24267 = r24264 / r24266;
        double r24268 = r24263 + r24267;
        double r24269 = -0.13857109526572012;
        double r24270 = 6.0;
        double r24271 = r24234 + r24270;
        double r24272 = r24269 / r24271;
        double r24273 = r24268 + r24272;
        double r24274 = 9.984369578019572e-06;
        double r24275 = r24274 / r24236;
        double r24276 = r24273 + r24275;
        double r24277 = 1.5056327351493116e-07;
        double r24278 = 8.0;
        double r24279 = r24234 + r24278;
        double r24280 = r24277 / r24279;
        double r24281 = r24276 + r24280;
        double r24282 = r24244 * r24281;
        double r24283 = r24228 * r24282;
        return r24283;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019315 
(FPCore (z)
  :name "Jmat.Real.gamma, branch z less than 0.5"
  :precision binary64
  (* (/ PI (sin (* PI z))) (* (* (* (sqrt (* PI 2)) (pow (+ (+ (- (- 1 z) 1) 7) 0.5) (+ (- (- 1 z) 1) 0.5))) (exp (- (+ (+ (- (- 1 z) 1) 7) 0.5)))) (+ (+ (+ (+ (+ (+ (+ (+ 0.99999999999980993 (/ 676.520368121885099 (+ (- (- 1 z) 1) 1))) (/ -1259.13921672240281 (+ (- (- 1 z) 1) 2))) (/ 771.32342877765313 (+ (- (- 1 z) 1) 3))) (/ -176.615029162140587 (+ (- (- 1 z) 1) 4))) (/ 12.5073432786869052 (+ (- (- 1 z) 1) 5))) (/ -0.138571095265720118 (+ (- (- 1 z) 1) 6))) (/ 9.98436957801957158e-6 (+ (- (- 1 z) 1) 7))) (/ 1.50563273514931162e-7 (+ (- (- 1 z) 1) 8))))))

Backtrace

match: no matching clause for 'binary64LC
match:error/opt/racket-7.2/collects/racket/match/runtime.rkt240
make-multiplication-subsubsubnode/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2660
make-multiplication-subsubsubnode/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2660
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2463
make-multiplication-subnode/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2440
make-multiplication-node/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt2340
map/opt/racket-7.2/collects/racket/private/map.rkt3513
f45/opt/racket-7.2/collects/racket/match/compiler.rkt50740
simplify/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt160
(unnamed)/opt/racket-7.2/collects/racket/contract/private/arrow-higher-order.rkt36033
location-do/data/pavpan/nightlies/herbie/fix-interface-bugs/src/programs.rkt640
location-do/data/pavpan/nightlies/herbie/fix-interface-bugs/src/programs.rkt640
(unnamed)/opt/racket-7.2/collects/racket/contract/private/arrow-higher-order.rkt36033
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1516
taylor-alt/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1450
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1667
gen-series!/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt1590
run-iter!/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3260
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3644
run-improve47/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3450
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.2/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.2/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.2/collects/racket/private/more-scheme.rkt26128