ports/166373: [x11] x11/libX11 fails if /usr/bin/cpp is clang

[Jakub Lach]

>Number:         166373
>Category:       ports
>Synopsis:       [x11] x11/libX11 fails if /usr/bin/cpp is clang
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Mar 24 13:20:08 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Jakub Lach
>Release:        9-STABLE amd64
>Organization:
>Environment:
9-STABLE amd64
>Description:
If WITH_CLANG_IS_CC= is set in src.conf, /usr/bin/cpp is clang, and configure fails:

checking for cpp... /usr/bin/cpp
checking if /usr/bin/cpp requires -undef... yes
checking if /usr/bin/cpp requires -traditional... configure: error: /usr/bin/cpp does not preserve whitespace with or without -traditional.  I don't know what to do.
===>  Script "configure" failed unexpectedly.
Please report the problem to x11 at FreeBSD.org [maintainer] and attach the
"/usr/obj/usr/ports/x11/libX11/work/libX11-1.4.4/config.log" including the
output of the failure of your make command. Also, it might be a good idea to
provide an overview of all packages installed on your system (e.g. an `ls
/var/db/pkg`).
*** Error code 1
>How-To-Repeat:

>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: