[native-compile] Debugging external package

[Arash Esbati <arash@gnu.org>]

Hi all,

I have successfully built Emacs with native-compile support on Win10 and
it works fine -- many thanks for this.

I've also installed powerline package from MELPA and Emacs fails to
compile the package with this error:

    x:/pathto/.emacs.d/elpa/powerline-20210428.1229/powerline.el:
    Error: List contains a loop ("22", . #0)
    Compilation finished.

How can I get more info about the error from the compiler?  Currently
Emacs tries to compile the package each time it starts (and fails) and
that makes the start slower.

I looked throught comp.el and the possible variables provided there are
"intended for debugging the compiler itself".

TIA for any hint.

Best, Arash