\[\frac{\pi}{\sin \left(\pi \cdot z\right)} \cdot \left(\left(\left(\sqrt{\pi \cdot 2} \cdot {\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}^{\left(\left(\left(1 - z\right) - 1\right) + 0.5\right)}\right) \cdot e^{-\left(\left(\left(\left(1 - z\right) - 1\right) + 7\right) + 0.5\right)}\right) \cdot \left(\left(\left(\left(\left(\left(\left(\left(0.99999999999980993 + \frac{676.520368121885099}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.13921672240281}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.32342877765313}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.615029162140587}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.5073432786869052}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.138571095265720118}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.98436957801957158 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.50563273514931162 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)\]
\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(0.99999999999980993 + \frac{676.520368121885099}{\left(\left(1 - z\right) - 1\right) + 1}\right) + \frac{-1259.13921672240281}{\left(\left(1 - z\right) - 1\right) + 2}\right) + \frac{771.32342877765313}{\left(\left(1 - z\right) - 1\right) + 3}\right) + \frac{-176.615029162140587}{\left(\left(1 - z\right) - 1\right) + 4}\right) + \frac{12.5073432786869052}{\left(\left(1 - z\right) - 1\right) + 5}\right) + \frac{-0.138571095265720118}{\left(\left(1 - z\right) - 1\right) + 6}\right) + \frac{9.98436957801957158 \cdot 10^{-6}}{\left(\left(1 - z\right) - 1\right) + 7}\right) + \frac{1.50563273514931162 \cdot 10^{-7}}{\left(\left(1 - z\right) - 1\right) + 8}\right)\right)
double f(double z) {
        double r113705 = atan2(1.0, 0.0);
        double r113706 = z;
        double r113707 = r113705 * r113706;
        double r113708 = sin(r113707);
        double r113709 = r113705 / r113708;
        double r113710 = 2.0;
        double r113711 = r113705 * r113710;
        double r113712 = sqrt(r113711);
        double r113713 = 1.0;
        double r113714 = r113713 - r113706;
        double r113715 = r113714 - r113713;
        double r113716 = 7.0;
        double r113717 = r113715 + r113716;
        double r113718 = 0.5;
        double r113719 = r113717 + r113718;
        double r113720 = r113715 + r113718;
        double r113721 = pow(r113719, r113720);
        double r113722 = r113712 * r113721;
        double r113723 = -r113719;
        double r113724 = exp(r113723);
        double r113725 = r113722 * r113724;
        double r113726 = 0.9999999999998099;
        double r113727 = 676.5203681218851;
        double r113728 = r113715 + r113713;
        double r113729 = r113727 / r113728;
        double r113730 = r113726 + r113729;
        double r113731 = -1259.1392167224028;
        double r113732 = r113715 + r113710;
        double r113733 = r113731 / r113732;
        double r113734 = r113730 + r113733;
        double r113735 = 771.3234287776531;
        double r113736 = 3.0;
        double r113737 = r113715 + r113736;
        double r113738 = r113735 / r113737;
        double r113739 = r113734 + r113738;
        double r113740 = -176.6150291621406;
        double r113741 = 4.0;
        double r113742 = r113715 + r113741;
        double r113743 = r113740 / r113742;
        double r113744 = r113739 + r113743;
        double r113745 = 12.507343278686905;
        double r113746 = 5.0;
        double r113747 = r113715 + r113746;
        double r113748 = r113745 / r113747;
        double r113749 = r113744 + r113748;
        double r113750 = -0.13857109526572012;
        double r113751 = 6.0;
        double r113752 = r113715 + r113751;
        double r113753 = r113750 / r113752;
        double r113754 = r113749 + r113753;
        double r113755 = 9.984369578019572e-06;
        double r113756 = r113755 / r113717;
        double r113757 = r113754 + r113756;
        double r113758 = 1.5056327351493116e-07;
        double r113759 = 8.0;
        double r113760 = r113715 + r113759;
        double r113761 = r113758 / r113760;
        double r113762 = r113757 + r113761;
        double r113763 = r113725 * r113762;
        double r113764 = r113709 * r113763;
        return r113764;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2020045 +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)))) (+ (+ (+ (+ (+ (+ (+ (+ 0.9999999999998099 (/ 676.5203681218851 (+ (- (- 1 z) 1) 1))) (/ -1259.1392167224028 (+ (- (- 1 z) 1) 2))) (/ 771.3234287776531 (+ (- (- 1 z) 1) 3))) (/ -176.6150291621406 (+ (- (- 1 z) 1) 4))) (/ 12.507343278686905 (+ (- (- 1 z) 1) 5))) (/ -0.13857109526572012 (+ (- (- 1 z) 1) 6))) (/ 9.984369578019572e-06 (+ (- (- 1 z) 1) 7))) (/ 1.5056327351493116e-07 (+ (- (- 1 z) 1) 8))))))

Backtrace

hash-ref: no value found for key key: '(fma #<enode 14(14)> #<enode 18(18)> #<enode 0(19)>)LC
for-loop/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding/regraph/egraph.rkt2706
update-leader!/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding/regraph/egraph.rkt2650
for-loop/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding/regraph/main.rkt772
prune-phase/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding/regraph/main.rkt740
for-loop/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/core/simplify.rkt804
for-loop/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/core/simplify.rkt762
(unnamed)/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/core/simplify.rkt560
(unnamed)/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/core/simplify.rkt380
simplify!/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/mainloop.rkt2240
run-iter!/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/mainloop.rkt3270
for-loop/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/mainloop.rkt3654
run-improve47/data/pavpan/nightlies/herbie/simplify-regraph-rebuilding-2/src/mainloop.rkt3460
.../more-scheme.rkt:261:28unknown
run/opt/racket-7.5/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.5/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.5/collects/racket/private/more-scheme.rkt26128