\[\left(\left(x \cdot y + z \cdot t\right) + a \cdot b\right) + c \cdot i\]
\left(\left(x \cdot y + z \cdot t\right) + a \cdot b\right) + c \cdot i
double f(double x, double y, double z, double t, double a, double b, double c, double i) {
        double r8312 = x;
        double r8313 = y;
        double r8314 = r8312 * r8313;
        double r8315 = z;
        double r8316 = t;
        double r8317 = r8315 * r8316;
        double r8318 = r8314 + r8317;
        double r8319 = a;
        double r8320 = b;
        double r8321 = r8319 * r8320;
        double r8322 = r8318 + r8321;
        double r8323 = c;
        double r8324 = i;
        double r8325 = r8323 * r8324;
        double r8326 = r8322 + r8325;
        return r8326;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019179 +o rules:numerics
(FPCore (x y z t a b c i)
  :name "Linear.V4:$cdot from linear-1.19.1.3, C"
  (+ (+ (+ (* x y) (* z t)) (* a b)) (* c i)))

Backtrace

result arity mismatch; expected number of values not received expected: 2 received: 1 in: local-binding form values...: 0LC
loop/data/pavpan/nightlies/herbie/various-cleanup/src/core/extraction.rkt252
(unnamed)/data/pavpan/nightlies/herbie/various-cleanup/src/core/simplify.rkt260
simplify!/data/pavpan/nightlies/herbie/various-cleanup/src/mainloop.rkt2170
run-improve43/data/pavpan/nightlies/herbie/various-cleanup/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