\[\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\left(\left(\sqrt{\pi \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.9999999999998099298181841732002794742584 + \frac{676.5203681218850988443591631948947906494}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.139216722402807135949842631816864014}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.3234287776531346025876700878143310547}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.6150291621405870046146446838974952698}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.50734327868690520801919774385169148445}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.1385710952657201178173096423051902092993}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.984369578019571583242346146658263705831 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.505632735149311617592788074479481785772 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)\]
\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 r38912 = atan2(1.0, 0.0);
        double r38913 = z;
        double r38914 = r38912 * r38913;
        double r38915 = sin(r38914);
        double r38916 = r38912 / r38915;
        double r38917 = 2.0;
        double r38918 = r38912 * r38917;
        double r38919 = sqrt(r38918);
        double r38920 = 1.0;
        double r38921 = r38920 - r38913;
        double r38922 = r38921 - r38920;
        double r38923 = 7.0;
        double r38924 = r38922 + r38923;
        double r38925 = 0.5;
        double r38926 = r38924 + r38925;
        double r38927 = r38922 + r38925;
        double r38928 = pow(r38926, r38927);
        double r38929 = r38919 * r38928;
        double r38930 = -r38926;
        double r38931 = exp(r38930);
        double r38932 = r38929 * r38931;
        double r38933 = 0.9999999999998099;
        double r38934 = 676.5203681218851;
        double r38935 = r38922 + r38920;
        double r38936 = r38934 / r38935;
        double r38937 = r38933 + r38936;
        double r38938 = -1259.1392167224028;
        double r38939 = r38922 + r38917;
        double r38940 = r38938 / r38939;
        double r38941 = r38937 + r38940;
        double r38942 = 771.3234287776531;
        double r38943 = 3.0;
        double r38944 = r38922 + r38943;
        double r38945 = r38942 / r38944;
        double r38946 = r38941 + r38945;
        double r38947 = -176.6150291621406;
        double r38948 = 4.0;
        double r38949 = r38922 + r38948;
        double r38950 = r38947 / r38949;
        double r38951 = r38946 + r38950;
        double r38952 = 12.507343278686905;
        double r38953 = 5.0;
        double r38954 = r38922 + r38953;
        double r38955 = r38952 / r38954;
        double r38956 = r38951 + r38955;
        double r38957 = -0.13857109526572012;
        double r38958 = 6.0;
        double r38959 = r38922 + r38958;
        double r38960 = r38957 / r38959;
        double r38961 = r38956 + r38960;
        double r38962 = 9.984369578019572e-06;
        double r38963 = r38962 / r38924;
        double r38964 = r38961 + r38963;
        double r38965 = 1.5056327351493116e-07;
        double r38966 = 8.0;
        double r38967 = r38922 + r38966;
        double r38968 = r38965 / r38967;
        double r38969 = r38964 + r38968;
        double r38970 = r38932 * r38969;
        double r38971 = r38916 * r38970;
        return r38971;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019310 +o rules:numerics
(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
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
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