Re: compiling ncurses on Darwin / Mac OS X

[Thomas Dickey]

On Mon, Jun 18, 2001 at 07:36:53AM -0700, Eugene Lee wrote:
> On Mon, Jun 18, 2001 at 09:42:49AM -0400, Thomas Dickey wrote:
> : On Mon, Jun 18, 2001 at 06:19:40AM -0700, Eugene Lee wrote:
> : > 
> : >   CFLAGS=-traditional-cpp ./configure
> 
> : > Could this be added to INSTALL, or maybe add this to the configure script?
> : 
> : I think I need more information (why Darwin has stuff in their header files
> : which is about 12-years obsolete).
> 
> >From what I understand, Apple's compiler uses a special cpp to handle
> it's Objective C syntax and precompiled headers, which unfortunately
> doesn't support GNU extensions.  Apple's cpp is on by default but can be
> switched to GNU's standard cpp via the -traditional-cpp flag.  So it's
> not really any kind of ncurses bug or a problem with Darwin's header
> files as much as it is with Apple's compiler.

I check for GNU extensions, but don't use (or rely) on them if they're
not present.  About all I know about Object C is that it uses a different
verb for including files - but iirc, it's supposed to accept #include
as well.  Perhaps Apple's compiler happens to have an option by the
same name, but this is what gcc's info says:

`-traditional-cpp'
     Attempt to support some aspects of traditional C preprocessors.
     Specifically:

        * Comments convert to nothing at all, rather than to a space.
          This allows traditional token concatenation.

        * In a preprocessing directive, the `#' symbol must appear as
          the first character of a line.

        * Macro arguments are recognized within string constants in a
          macro definition (and their values are stringified, though
          without additional quote marks, when they appear in such a
          context).  The preprocessor always considers a string
          constant to end at a newline.

        * The predefined macro `__STDC__' is not defined when you use
          `-traditional', but `__GNUC__' is (since the GNU extensions
          which `__GNUC__' indicates are not affected by
          `-traditional').  If you need to write header files that work
          differently depending on whether `-traditional' is in use, by
          testing both of these predefined macros you can distinguish
          four situations: GNU C, traditional GNU C, other ANSI C
          compilers, and other old C compilers.  The predefined macro
          `__STDC_VERSION__' is also not defined when you use
          `-traditional'.  *Note Standard Predefined Macros:
          (cpp.info)Standard Predefined, for more discussion of these
          and other predefined macros.

        * The preprocessor considers a string constant to end at a
          newline (unless the newline is escaped with `\').  (Without
          `-traditional', string constants can contain the newline
          character as typed.)

(While I've made an attempt to work around broken cpp's such as on AIX 3.x,
which implement a mix of K&R/ANSI, it's not certain that ncurses would
work properly if you set the cpp to "-traditional-cpp" even if it compiled).


 
> I ran into similar problems with compiling Vim pre-5.8, which required a
> similar fix.  A quick search turned up tons of similar fixes from people
> porting to Darwin.

Vim's not written in ANSI C (it's extended C, which is a bit different).

-- 
Thomas E. Dickey <address@hidden>
http://dickey.his.com
ftp://dickey.his.com