On Mon, Nov 28, 2022 at 2:42 PM Eli Zaretskii <eliz@gnu.org> wrote:

Why is this weird?  These files are needed early at startup, when Emacs is
still unable to do anything fancy, so how is it "weird" that relative file
names are interpreted as relative to where Emacs runs?  Are you aware of any
other programs that interpret relative file names differently?

It is used also for files that are not required early at startup (unless you consider "early at startup" native-compiling the .el/.elc files required or loaded in init.el).

If the effect surprises you, don't add relative file names to the variable.

For sure.
 
You aren't supposed to anyway; AFAIR this option is only used during the
build, if at all.

 I don't disagree, but that's not evident reading native-comp-eln-load-path's docstring.

Anyway, the fact that if you set a relative dir ./test-compile in that variable both ~/.emacs.d/test-compile and src/test-compile directories are created is also a bug.