Log Message:
Not setting GCC_REQD for OpenBSD/sparc64. None of the lang/gcc4* packages
build on OpenBSD 5.6/sparc64 at the moment. However, the boost-*
packages build quite well with the system gcc:

# gcc -v
Reading specs from /usr/lib/gcc-lib/sparc64-unknown-openbsd5.6/4.2.1/specs
Target: sparc64-unknown-openbsd5.6
Configured with: OpenBSD/sparc64 system compiler
Thread model: posix
gcc version 4.2.1 20070719
# pkg_info | grep boost
boost-headers-1.56.0 Boost is a set of free, peer-reviewed, C++ libraries.  The \ 
emphasis is on
boost-jam-1.56.0    Boost is a set of free, peer-reviewed, C++ libraries.  The \ 
emphasis is on