Preprocessor woes

[Mark Kettenis]

   From: "Zack Weinberg" <zackw@stanford.edu>
   Date: Fri, 5 Jan 2001 14:40:26 -0800

   On Fri, Jan 05, 2001 at 09:45:55PM +0000, Neil Booth wrote:
   > Mark Kettenis wrote:-
   > 
   > > occur.  Since the SHLIB_COMPAT macro uses the ISO C ## concatenation
   > > operator, -traditional messes things up.  Is there any chance at
   > > convincing the GCC folks to provide a preprocessor that's backwards
   > > compatible with cccp?
   > 
   > Try using the portable CONCAT macros that GCC does.  That's much
   > simpler than rewriting tradcpp (which is what this would require).

   Concatenation with ## has never worked in -traditional mode.  The real
   problem is something else.

We used to preprocess this stuff without -traditional.  Then the new
preprocessor introduced some whitespace in funny places; see
< http://sources.redhat.com/ml/libc-alpha/2000-11/msg00262.html >.  Then
Ulrich switched to -traditional (I think after a suggestion from you
or Neil).  And now the Hurd doesn't build anymore :-(.

I cc'd you GCC folks to make you aware that the new preprocessor is
causing some real pain, and I saw no way out.  Fortunately there are
at least two workarounds (thanks Neil and Jakub).  I still think it
would be better if the new integrated preprocessor would be backwards
compatible with the old one, even for sources that are not C.

Mark