Exception for Trigonometry B

Math

\[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\]

C

double f(double x) {
        double r1092902 = 1.0;
        double r1092903 = x;
        double r1092904 = tan(r1092903);
        double r1092905 = r1092904 * r1092904;
        double r1092906 = r1092902 - r1092905;
        double r1092907 = r1092902 + r1092905;
        double r1092908 = r1092906 / r1092907;
        return r1092908;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019173 
(FPCore (x)
  :name "Trigonometry B"
  (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))

Backtrace

hash-ref: no value found for key key: #<enode 682(682)>		L	C
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	197	2
extractor-extract	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	196	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	35	2
(unnamed)	/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt	26	0
simplify!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	217	0
run-iter!	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	320	0
for-loop	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	354	4
run-improve43	/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt	339	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28