\[\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t\]
\left(\left(\log \left(x + y\right) + \log z\right) - t\right) + \left(a - 0.5\right) \cdot \log t
double f(double x, double y, double z, double t, double a) {
        double r8171 = x;
        double r8172 = y;
        double r8173 = r8171 + r8172;
        double r8174 = log(r8173);
        double r8175 = z;
        double r8176 = log(r8175);
        double r8177 = r8174 + r8176;
        double r8178 = t;
        double r8179 = r8177 - r8178;
        double r8180 = a;
        double r8181 = 0.5;
        double r8182 = r8180 - r8181;
        double r8183 = log(r8178);
        double r8184 = r8182 * r8183;
        double r8185 = r8179 + r8184;
        return r8185;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019191 +o rules:numerics
(FPCore (x y z t a)
  :name "Numeric.SpecFunctions:logGammaL from math-functions-0.1.5.2"
  (+ (- (+ (log (+ x y)) (log z)) t) (* (- a 0.5) (log t))))

Backtrace

get-representation: Unknown representation #fLC
loop/data/pavpan/nightlies/herbie/interface2/src/points.rkt1224
prepare-points/data/pavpan/nightlies/herbie/interface2/src/points.rkt1460
setup-prog!34/data/pavpan/nightlies/herbie/interface2/src/mainloop.rkt670
run-improve43/data/pavpan/nightlies/herbie/interface2/src/mainloop.rkt3390
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128
run/opt/racket-7.0/share/pkgs/profile-lib/main.rkt392
profile-thunk16/opt/racket-7.0/share/pkgs/profile-lib/main.rkt90
(unnamed)/opt/racket-7.0/collects/racket/private/more-scheme.rkt26128