amd64/173869: buildworld breaks with clang

[Z Beeblebrox]

>Number:         173869
>Category:       amd64
>Synopsis:       buildworld breaks with clang
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri Nov 23 18:20:00 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Z Beeblebrox
>Release:        STABLE
>Organization:
>Environment:
FreeBSD 9.1-PRERELEASE #2 r242867 amd64
>Description:
In /etc/src.conf I have set:
WITHOUT_GCC= yes
WITH_CLANG= yes
WITH_CLANG_EXTRAS= yes
WITH_CLANG_IS_CC= yes
Normally I use ccache and -J but they were disabled prior to a clean buildworld to test the problem.

Under these conditions, buildworld solidly breaks with: 
===> gnu/lib/libstdc++ (all)
building shared library libstdc++.so.6
/usr/obj/asp/src/tmp/usr/bin/ld: warning: creating a DT_TEXTREL in a shared object.
clang: error: linker command failed with exit code 1 (use -v to see invocation)
*** [libstdc++.so.6] Error code 1
Stop in /usr/src/gnu/lib/libstdc++.

Detailed discussion here: http://freebsd.1045724.n5.nabble.com/buildworld-with-clang-breaks-because-no-cc-td5763472.html
>How-To-Repeat:
as above
>Fix:
N/A

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