Re: CEDET calls cpp -E -dM -x c++ /dev/null

[Eli Zaretskii]

> Date: Wed, 1 Jul 2009 21:06:17 +0200
> From: Lennart Borgman <address@hidden>
> Cc: Alex Ott <address@hidden>, "Eric M. Ludlam" <address@hidden>
> 
> CEDET does the call above in semantic-gcc-setup. Doing that from the
> command line using MingGW on w32 fails.
> 
> It fails because /dev/null is not valid on w32. Shouldn't it be NUL
> there?

Yes.

> However looking through Emacs lisp sources I see several uses
> of just /dev/null.

They are all bugs, unless they are intended to work only with Unix and
GNU systems.

> Wouldn't it be better to use some defsubst for this?

We already have one: the Lisp variable null-device holds the name of
the device appropriate for the underlying OS.

> Now, if the command instead is
> 
>     cpp -E -dM -x c++ nul
> 
> it fails for me with
> 
>   cpp: installation problem, cannot exec `cc1plus': No such file or directory

This works for me.  What version of cpp do you have?  I have this:

    D:\usr\eli\data>cpp --version
    cpp (GCC) 3.4.2 (mingw-special)
    Copyright (C) 2004 Free Software Foundation, Inc.
    This is free software; see the source for copying conditions.  There is NO
    warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.