\[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}\]
x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}
double f(double x, double y, double z, double t) {
        double r232236 = x;
        double r232237 = 1.0;
        double r232238 = y;
        double r232239 = r232237 - r232238;
        double r232240 = z;
        double r232241 = exp(r232240);
        double r232242 = r232238 * r232241;
        double r232243 = r232239 + r232242;
        double r232244 = log(r232243);
        double r232245 = t;
        double r232246 = r232244 / r232245;
        double r232247 = r232236 - r232246;
        return r232247;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019323 
(FPCore (x y z t)
  :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
  :precision binary64

  :herbie-target
  (if (< z -2.8874623088207947e+119) (- (- x (/ (/ (- 0.5) (* y t)) (* z z))) (* (/ (- 0.5) (* y t)) (/ (/ 2 z) (* z z)))) (- x (/ (log (+ 1 (* z y))) t)))

  (- x (/ (log (+ (- 1 y) (* y (exp z)))) t)))

Backtrace

get-representation: Unknown representation realLC
(unnamed)/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt653
filter/opt/racket-7.2/collects/racket/private/list.rkt2562
infer-splitpoints/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/regimes.rkt340
get-final-combination/data/pavpan/nightlies/herbie/fix-interface-bugs/src/mainloop.rkt3690
(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