Re: Patch to cccp.c to display omitted default include directories

[Zack Weinberg <zack at rabi dot columbia dot edu>]

On Tue, 02 Mar 1999 01:40:51 -0700, Jeffrey A Law wrote:
>
>  In message <199902232206.OAA20499@elmo.cygnus.com>you write:
>  > Hi Guys,
>  > 
>  >   I would like to submit the following little patch which provided
>  >   some useful debugging information for when I was tracking down a 
>  >   configuration problem.  The patch extends the -v output of 'cpp' so
>  >   that it also lists the default include directories which were never
>  >   appended to the include directory chain.
>  > 
>  > Cheers
>  > 	Nick
>  > 
>  > 
>  > Tue Feb 23 14:00:40 1999  Nick Clifton  <nickc@cygnus.com>
>  > 
>  > 	* cccp.c (struct default_include): Add 'included' field.
>  > 	(main): Set 'included' field when a default include directory
>  > 	is added to the chain.  If -v is specified list all default
>  > 	include directories which do not get appended to the chain.
>Can you do the same thing for cpplib?

cpplib's include-path handling code is completely different and Nick's
patch does not translate well.  I added something similar in the patch
I posted last week ("cpplib: initialization overhaul").  That's
http://egcs.cygnus.com/ml/egcs-patches/1999-02/msg00728.html.

>It might make sense to have this conditional on a warning flag (a generic
>one, or a specific one would be fine by me).

If we put this on a warning flag, you'll get messages for every .c
file in a large build when a directory doesn't exist.  Some of the
directories on the default include path may legitimately not exist
(e.g. /usr/local/include).  I think -v is the right place.

>It might be good improve the warning to note why those directories did not
>get added to the chain (because they didn't exist? any other reason they
>would not get added?)

In cpplib, because they don't exist or because they are duplicates.
My patch differentiates.  It'd be nice to drop empty directories too,
but there isn't a simple way to detect that as far as I know.

zw