BOOST_STATIC_ASSERT doesn't produce a useful error message with gcc 3.3. E.g.: #include <boost/static_assert.hpp> BOOST_STATIC_ASSERT(0); produces % g++ -c -o bsa.o bsa.cpp bsa.cpp:3: error: invalid application of `sizeof' to an incomplete type According to <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15337>, this is fixed, but some of use will still be using gcc 3.3 for a while. It turns out the version of BOOST_STATIC_ASSERT used when BOOST_INTEL_CXX_VERSION is defined works for the offending versions of gcc, too: #include <boost/static_assert.hpp> # define BOOST_STATIC_ASSERT_1( B ) \ typedef char BOOST_JOIN(boost_static_assert_typedef_, __LINE__) \ [ ::boost::STATIC_ASSERTION_FAILURE< (bool)( B ) >::value ] BOOST_STATIC_ASSERT_1(0); produces % g++ -c -o bsa.o bsa.cpp bsa.cpp:6: error: incomplete type `boost::STATIC_ASSERTION_FAILURE<false>' does not have member `value' Could that version be used for gcc 3.3 and 3.4.0 in the upcoming boost 1.32? FYI: % gcc -v Reading specs from /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.4/specs Configured with: /var/tmp/portage/gcc-3.3.4-r1/work/gcc-3.3.4/configure --prefix=/usr --bindir=/usr/i686-pc-linux-gnu/gcc-bin/3.3 --includedir=/usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.4/include --datadir=/usr/share/gcc-data/i686-pc-linux-gnu/3.3 --mandir=/usr/share/gcc-data/i686-pc-linux-gnu/3.3/man --infodir=/usr/share/gcc-data/i686-pc-linux-gnu/3.3/info --enable-shared --host=i686-pc-linux-gnu --target=i686-pc-linux-gnu --with-system-zlib --enable-languages=c,c++ --enable-threads=posix --enable-long-long --disable-checking --disable-libunwind-exceptions--enable-cstdio=stdio --enable-version-specific-runtime-libs --with-gxx-include-dir=/usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.4/include/g++-v3 --with-local-prefix=/usr/local --enable-shared --enable-nls --without-included-gettext --disable-multilib --enable-__cxa_atexit --enable-clocale=generic Thread model: posix gcc version 3.3.4 20040623 (Gentoo Linux 3.3.4-r1, ssp-3.3.2-2, pie-8.7.6) -- ^.-.^ Mark Purtill (("))