math.arg on complex

Specification

?
\[\begin{array}{l} \\ \tan^{-1}_* \frac{im}{re} \end{array} \]
(FPCore (re im) :precision binary64 (atan2 im re))
double code(double re, double im) {
	return atan2(im, re);
}
real(8) function code(re, im)
    real(8), intent (in) :: re
    real(8), intent (in) :: im
    code = atan2(im, re)
end function
public static double code(double re, double im) {
	return Math.atan2(im, re);
}
def code(re, im):
	return math.atan2(im, re)
function code(re, im)
	return atan(im, re)
end
function tmp = code(re, im)
	tmp = atan2(im, re);
end
code[re_, im_] := N[ArcTan[im / re], $MachinePrecision]
\begin{array}{l}

\\
\tan^{-1}_* \frac{im}{re}
\end{array}

Reproduce

?
herbie shell --seed 2024288 
(FPCore (re im)
  :name "math.arg on complex"
  :precision binary64
  (atan2 im re))

Please file a bug report with this information.

Backtrace

error: contract violation expected: string? given: 'atan2.f64LC
f407.../match/compiler.rkt55940
loop.../private/map.rkt4019
loop.../private/map.rkt4019
loop.../private/map.rkt4019
compile-expr/home/nightlies/herbie/bhargav-log-space/src/core/explain.rkt840
explain/home/nightlies/herbie/bhargav-log-space/src/core/explain.rkt7130
explain!/home/nightlies/herbie/bhargav-log-space/src/core/mainloop.rkt3230
run-improve!/home/nightlies/herbie/bhargav-log-space/src/core/mainloop.rkt450
get-alternatives/report/home/nightlies/herbie/bhargav-log-space/src/api/sandbox.rkt1860
(unnamed)/home/nightlies/herbie/bhargav-log-space/src/api/sandbox.rkt2826
(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