> To be precise,
>
>     M-: (eval '(let (...) (c-align-cpp-indent-to-body)))
>
> runs correctly, but fails to stop in c-align-..-body, even though it is
> instrumented for edebug.

That would be a bug.  I can't reproduce it here.  I did:

    % src/emacs -Q src/emacs-module.c lisp/progmodes/cc-cmds.el
    C-s cpp-indent RET
    C-u C-M-x
    C-x o
    M-: (eval '(let ((c-syntactic-context nil)) (c-align-cpp-indent-to-body))) RET

and it landed me in edebugging the body of `c-align-cpp-indent-to-body`.


        Stefan