\[\left(x \cdot y + z \cdot t\right) + a \cdot b\]
\left(x \cdot y + z \cdot t\right) + a \cdot b
double f(double x, double y, double z, double t, double a, double b) {
        double r8291 = x;
        double r8292 = y;
        double r8293 = r8291 * r8292;
        double r8294 = z;
        double r8295 = t;
        double r8296 = r8294 * r8295;
        double r8297 = r8293 + r8296;
        double r8298 = a;
        double r8299 = b;
        double r8300 = r8298 * r8299;
        double r8301 = r8297 + r8300;
        return r8301;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019179 
(FPCore (x y z t a b)
  :name "Linear.V3:$cdot from linear-1.19.1.3, B"
  (+ (+ (* x y) (* z t)) (* a b)))

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