STATIC_ASSERT is outside of the claimed WiredTiger name space (and
far too likely to be seen in the field), prefix it with WT
SIZE_CHECK is local to include/verify_build.h, make sure it stays
there.
Simplify gcc.h, don't repeat the GCC atomic builtins, just use one version.
Break hardware.h up into gcc.h and lint.h (hardware.h is still there,
but it's mostly empty).
Remove need for gcc.h from various benchmarking/test programs.