FreeBSD 10.0-CURRENT: messed up the ports and system (gcc46 won't compile) and need to repair - how?

Since the change of one of my boxes to FreeBSD 10.0 and some
accindetally build of ports without the suggested settings for UNAME_r
before building ports, I think I've messed up with some ports and need
some advice how to fixate the problem.

Some develish motivation drove me today building gcc46/gotoblas and gcc
fails to build with the below shown message. But this is not the only
port that rushes into problems.

Thing is: I do not know wether I messed up the system or this is simply
the very often mentioned problem due to the two-digit versioning of the
most recent CURRENT.

Except ANJUTA, which complains about a non-working subversion module due
to some lack in a libgdbm port (which also won't build) everything works
fine and I can stand this for the next one or two weeks to wait for a
general fixation, but it would be a good attempt, I think, to start
fixating my messed up system now, if there is any real mess I did.

Any advice?


Thanks in advance.

Oliver

P.S.: On FreeBSD 9.0-BETA3 everything runs well, except the usual little
horror with legacy gcc 4.2 versus CLANG. So I expect the problems to be
real 10.0-issues.

===

rm -f include-fixed/README
cp .././../gcc-4.6-20111007/gcc/../fixincludes/README-fixinc
include-fixed/README
chmod a+r include-fixed/README
echo timestamp > stmp-int-hdrs
rm gcov.pod fsf-funding.pod cpp.pod gcc.pod gfdl.pod
gmake[3]: Leaving directory `/usr/ports/lang/gcc46/work/build/gcc'
mkdir x86_64-portbld-freebsd10.0/libgcc
Checking multilib configuration for libgcc...
Configuring stage 1 in x86_64-portbld-freebsd10.0/libgcc
configure: creating cache ./config.cache
checking for --enable-version-specific-runtime-libs... no
checking for a BSD-compatible install... /usr/bin/install -c -o root -g
wheel
checking for gawk... gawk
checking build system type... x86_64-portbld-freebsd10.0
checking host system type... x86_64-portbld-freebsd10.0
checking for x86_64-portbld-freebsd10.0-ar...
/usr/local/x86_64-portbld-freebsd10.0/bin/ar
checking for x86_64-portbld-freebsd10.0-lipo... lipo
checking for x86_64-portbld-freebsd10.0-nm...
/usr/ports/lang/gcc46/work/build/./gcc/nm
checking for x86_64-portbld-freebsd10.0-ranlib...
/usr/local/x86_64-portbld-freebsd10.0/bin/ranlib
checking for x86_64-portbld-freebsd10.0-strip...
/usr/local/x86_64-portbld-freebsd10.0/bin/strip
checking whether ln -s works... yes
checking for x86_64-portbld-freebsd10.0-gcc...
/usr/ports/lang/gcc46/work/build/./gcc/xgcc
-B/usr/ports/lang/gcc46/work/build/./gcc/
-B/usr/local/x86_64-portbld-freebsd10.0/bin/
-B/usr/local/x86_64-portbld-freebsd10.0/lib/ -isystem
/usr/local/x86_64-portbld-freebsd10.0/include -isystem
/usr/local/x86_64-portbld-freebsd10.0/sys-include  
checking for suffix of object files... configure: error: in
`/usr/ports/lang/gcc46/work/build/x86_64-portbld-freebsd10.0/libgcc':
configure: error: cannot compute suffix of object files: cannot compile
See `config.log' for more details.
gmake[2]: *** [configure-stage1-target-libgcc] Error 1
gmake[2]: Leaving directory `/usr/ports/lang/gcc46/work/build'
gmake[1]: *** [stage1-bubble] Error 2
gmake[1]: Leaving directory `/usr/ports/lang/gcc46/work/build'
gmake: *** [bootstrap-lean] Error 2
*** Error code 1

Stop in /usr/ports/lang/gcc46.
*** Error code 1

Stop in /usr/ports/lang/gcc46.

===>>> make failed for lang/gcc46
===>>> Aborting update

===>>> Update for lang/gcc46 failed
===>>> Aborting update