Another installation issue with libstdc++. Whats the cleanest way to address this?

checking whether we are using the GNU C++ compiler… yes
checking whether /home/gordon/Applications/ellcc/bin/ecc++ accepts -g… yes
checking how to run the C preprocessor… cc -E
checking whether GCC or Clang is our host compiler… clang
checking build system type… x86_64-unknown-linux-gnu
checking host system type… x86_64-unknown-linux-gnu
checking target system type… x86_64-unknown-linux-gnu
checking type of operating system we’re going to host on… Linux
checking type of operating system we’re going to target… Linux
checking target architecture… x86_64
checking whether Clang is new enough… yes
checking whether Clang will select a modern C++ standard library… no
configure: error:
We detected a missing feature in the standard C++ library that was known to be
missing in libstdc++4.6 and implemented in libstdc++4.7. There are numerous
C++11 problems with 4.6’s library, and we don’t support GCCs or libstdc++ older
than 4.7. You will need to update your system and ensure Clang uses the newer
standard library.

If this error is incorrect or you need to force things to work, you may pass
‘–disable-compiler-version-checks’ to configure to bypass this test.
make: *** [llvm.configure] Error 1