Quotient of products

Specification

?
\[\begin{array}{l} \\ \frac{a1 \cdot a2}{b1 \cdot b2} \end{array} \]
(FPCore (a1 a2 b1 b2) :precision binary64 (/ (* a1 a2) (* b1 b2)))
double code(double a1, double a2, double b1, double b2) {
	return (a1 * a2) / (b1 * b2);
}
real(8) function code(a1, a2, b1, b2)
    real(8), intent (in) :: a1
    real(8), intent (in) :: a2
    real(8), intent (in) :: b1
    real(8), intent (in) :: b2
    code = (a1 * a2) / (b1 * b2)
end function
public static double code(double a1, double a2, double b1, double b2) {
	return (a1 * a2) / (b1 * b2);
}
def code(a1, a2, b1, b2):
	return (a1 * a2) / (b1 * b2)
function code(a1, a2, b1, b2)
	return Float64(Float64(a1 * a2) / Float64(b1 * b2))
end
function tmp = code(a1, a2, b1, b2)
	tmp = (a1 * a2) / (b1 * b2);
end
code[a1_, a2_, b1_, b2_] := N[(N[(a1 * a2), $MachinePrecision] / N[(b1 * b2), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{a1 \cdot a2}{b1 \cdot b2}
\end{array}

Reproduce

?
herbie shell --seed 2024012 
(FPCore (a1 a2 b1 b2)
  :name "Quotient of products"
  :precision binary64

  :herbie-target
  (* (/ a1 b1) (/ a2 b2))

  (/ (* a1 a2) (* b1 b2)))

Please file a bug report with this information.

Backtrace

car: contract violation expected: pair? given: '#(#s(si 0 224) (#s(si 2 100)))LC
err-lsts->split-indices/home/nightlies/herbie/zane-regimes-2/src/core/regimes.rkt1760
option-on-expr/home/nightlies/herbie/zane-regimes-2/src/core/regimes.rkt1060
infer-splitpoints/home/nightlies/herbie/zane-regimes-2/src/core/regimes.rkt390
loop/home/nightlies/herbie/zane-regimes-2/src/core/regimes.rkt272
extract!/home/nightlies/herbie/zane-regimes-2/src/mainloop.rkt3520
run-improve!/home/nightlies/herbie/zane-regimes-2/src/mainloop.rkt3260
get-alternatives/report/home/nightlies/herbie/zane-regimes-2/src/sandbox.rkt1500
(unnamed)/home/nightlies/herbie/zane-regimes-2/src/sandbox.rkt2466
(unnamed)/usr/share/racket/pkgs/profile-lib/main.rkt4010
profile-thunk/usr/share/racket/pkgs/profile-lib/main.rkt90
(unnamed)/usr/share/racket/collects/racket/engine.rkt4224