\[1 - \log \left(1 - \frac{x - y}{1 - y}\right)\]
1 - \log \left(1 - \frac{x - y}{1 - y}\right)
double f(double x, double y) {
        double r21215 = 1.0;
        double r21216 = x;
        double r21217 = y;
        double r21218 = r21216 - r21217;
        double r21219 = r21215 - r21217;
        double r21220 = r21218 / r21219;
        double r21221 = r21215 - r21220;
        double r21222 = log(r21221);
        double r21223 = r21215 - r21222;
        return r21223;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019310 +o rules:numerics
(FPCore (x y)
  :name "Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B"
  :precision binary64

  :herbie-target
  (if (< y -81284752.619472414) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))) (if (< y 3.0094271212461764e25) (log (/ (exp 1) (- 1 (/ (- x y) (- 1 y))))) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y)))))))

  (- 1 (log (- 1 (/ (- x y) (- 1 y))))))

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
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
for-loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt8711
parse-loop373/opt/racket-7.2/collects/racket/match/compiler.rkt41815
parse-loop373/opt/racket-7.2/collects/racket/match/compiler.rkt41815
append-map/opt/racket-7.2/collects/racket/list.rkt5862
simplify-node/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/reduce.rkt480
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
hash-ref!/opt/racket-7.2/collects/racket/private/more-scheme.rkt3762
(unnamed)/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/taylor.rkt4515
hash-ref!/opt/racket-7.2/collects/racket/private/more-scheme.rkt3762
(unnamed)/opt/racket-7.2/collects/racket/contract/private/arrow-higher-order.rkt36033
(unnamed)/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/taylor.rkt6815
hash-ref!/opt/racket-7.2/collects/racket/private/more-scheme.rkt3762
loop/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/taylor.rkt874
approximate9/data/pavpan/nightlies/herbie/fix-interface-bugs/src/core/taylor.rkt120
(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