Which site-lisp file was loaded, default.el or default.elc?

Question

I'm setting up some site-wide default configuration in the site-lisp directory, and trying to figure out whether emacs is loading the byte-compiled default.elc or default.el. I haven't applied any other configuration, such as load-prefer-newer.

With the following default.el

(defvar foo nil)

and having compiled it so both the .el and .elc files are present, if I run describe-symbol on foo I'm shown:

foo is a variable defined in 'default.el'

and the *Messages* buffer shows the path to default.el (as if it loaded it to look up the symbol, though I don't know if that's actually what it means).

If I remove the .el file leaving only the .elc file, then start emacs and again describe foo it shows:

foo is a variable defined in 'default.elc'

and in the *Messages* buffer I see the path to default.elc.

I had expected it to load the byte-compiled .elc file when both were present, but can't tell if that's what's happening. How can I check?

Answer 1

C-h v load-history

Then search the variable value (in buffer *Help*) for the library you're interested in, e.g. default.el or default.elc.