Linking issue with _GLIBCXX_DEBUG on 4.7/google

[Oleg Smolsky <oleg dot smolsky at riverbed dot com>]

Hey all, I've just hit an issue when using _GLIBCXX_DEBUG together with 
Google's gcc 4.7 built using --enable-symvers=gnu-versioned-namespace 
flag. The issue is specific to unordered_mulimap and can be reproduced 
using the following:

struct MyType
{
};

#if 1
using MyMap = std::multimap<std::string, MyType *>;    // works
#else
using MyMap = std::unordered_multimap<std::string, MyType *>;    // 
fails to link
#endif

MyMap m;
m.insert({"blah"}, new MyType});

The latter variant fails to link with the following message:

In function 
`__gnu_debug::_Safe_unordered_container_base::~_Safe_unordered_container_base()':
statmgr.cc:(.text._ZN11__gnu_debug30_Safe_unordered_container_baseD2Ev[_ZN11__gnu_debug30_Safe_unordered_container_baseD5Ev]+0x15): 
undefined reference to 
`__gnu_debug::_Safe_unordered_container_base::_M_detach_all()'

The compiler was configured as follows:
Configured with: ../gcc47-google/configure 
--prefix=/opt/gcc-google-4.7-v7 --enable-languages=c,c++,lto 
--with-mpfr=/opt/gcc-4.6-rbt --with-cloog=/opt/gcc-4.6-rbt 
--with-mpc=/opt/gcc-4.6-rbt --with-gmp=/opt/gcc-4.6-rbt 
--with-system-zlib --disable-multilib --enable-lto 
--with-build-config=bootstrap-lto --with-fpmath=sse --enable-gold=yes 
--enable-cloog-backend=isl --disable-cloog-version-check 
--program-suffix=-google-4.7 --enable-symvers=gnu-versioned-namespace 
CFLAGS=-O3 CXXFLAGS='-O3 -mtune=core2'

Could someone shed some light on this please?

Thanks!
Oleg.