Problem with eval-when-compile at macro expansion time

Consider an elisp file containing this: (eval-when-compile (defvar x (cl-macroexpand-all '(eval-when-compile (error "evaluated")))) nil) If this is byte compiled in XEmacs 21.4.6, the error "evaluated" is signalled inside the byte compiler. It turns out that the content of the `eval-when-compile' is evaluated during the `cl-macroexpand-all' call. I did not expect `error' to be evaluated at that point since it's a function and not a macro. This is a regression from (at least) XEmacs 20.4 and 19.16, where x is simply assigned the quoted value (error "evaluated") at compile time. FSF Emacs also works that way.