"Over-specification in `h'-direction" but not actually overspecified

[RalfJung]

I am seeing this warning:

main.tex: [geometry] Over-specification in `h'-direction. (page 1)

My geometry command looks as follows:

\geometry{a4paper,left=21.5mm,right=21.5mm,includemp,marginparsep=8mm,marginparwidth=48mm,%
   top=27.5mm,headsep=2\baselineskip,textheight=49\baselineskip,headheight=\baselineskip}

In particular, the textwidth is left unspecified, so I don't think this is an actual over-specification.

This is with texlive 2020.20200417 as packaged in Debian testing.

[SurJector]

I think a \Gm@hbodyfalse and a \Gm@vbodyfalse are missing in \Gm@clean. Precisely, after \let\Gm@textwidth\@undefined, I think there should be a \Gm@hbodyfalse and after \let\Gm@textheight\@undefined, I think there should be a \Gm@vbodyfalse.