/usr/include/c++/v1/array:295:24: fatal error: recursive template
instantiation exceeded maximum depth of 256
I am not sure if this is a clang problem or a libc++ problem. Does
anyone know what could be going wrong?
While you can increase clang's template recursion depth with "-ftemplate-depth"[*]
(for me -ftemplate-depth=1039 was the lowest that allowed your test to compile), I
think such a huge recursion depth is a quality-of-implementation issue, either with
boost or libc++. As the recursion happens in libc++'s std::__1::__make_tuple_types_imp,
I would suggest you file a bug in libc++'s bug tracker: <http://llvm.org/bugs>.