WITHOUT_GCC flag disables installation of /usr/bin/cpp too -- is it Ok?

[Sean C. Farley]

On Fri, 9 Sep 2011, Benjamin Kaduk wrote:

> On Wed, 7 Sep 2011, Lev Serebryakov wrote:
>
>> Hello, Dimitry.
>> You wrote 7 сентября 2011 г., 21:17:20:
>> 
>> I think, that /usr/bin/cpp is valuable by itself, as it is handy 
>> generic preprocessor tool, useful for preparing complex ipfw scripts, 
>> for example. All others are bundled together, for sure.
>
> I am not really convinced.  /usr/bin/cpp is the C preprocessor, and it is 
> only required to emit output that its bundled C compiler will accept as 
> input.  In particular, it can do whatever it wants with whitespace, wrapping 
> and unwrapping lines, outputting other spurious text, &c..
> From cpp(1):
>       The C preprocessor is intended to be used only with C, C++, and Objec-
>       tive-C source code.  In the past, it has been abused as a general text
>       processor.  It will choke on input which does not obey C's lexical
>       rules.  For example, apostrophes will be interpreted as the beginning
>       of character constants, and cause errors.  Also, you cannot rely on it
>       preserving characteristics of the input which are not significant to
>       C-family languages.  If a Makefile is preprocessed, all the hard tabs
>       will be removed, and the Makefile will not work.
> The (incredibly brain-dead) build system at $work runs cpp on a Makefile, 
> which I had to hack around in order to get things to work.  It's really an 
> ugly hack, though, and is not at all robust.  I wish I didn't have to.
>
> If you want a general-purpose macro processor, please consider using 
> something that was designed as a general-purpose macro processor (e.g. m4(1) 
> which is in base) -- abusing cpp(1) is just asking for weird/subtle errors to 
> be introduce in the future.

Another option may be to install devel/ucpp.  I have not used it before, 
but it may be good enough for preparing ipfw scripts.

Sean
-- 
scf at FreeBSD.org