Re: [Boost-users] [bcp] [shared_ptr] [wave] Extracting subset of boostforshared_ptr - 3.2MB?

David Abrahams writes:

"John Maddock" writes:

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Unfortunately bcp isn't smart enough to not look into optional dependencies that are guarded by #ifdef. In this particular case it follows the dependency to detail/quick_allocator.hpp, which in turn brings in the type_traits and mpl libraries. But quick_allocator.hpp is only used if you #define BOOST_SP_USE_QUICK_ALLOCATOR.

Peter, this comes up so often, I wonder is it worth while "hiding" that optional dependency behind a #define, as in:

#define BOOST_SP_QA

#ifdef BOOST_SP_USE_QUICK_ALLOCATOR #include BOOST_SP_QA #endif

If doing that works to fool bcp, we need a better system. It would be a lot of work, but maybe it would be the first real use of Wave as a library rather than just as a preprocessor. We could use the graph library to do a real search with some knowledge of compiler and configuration #defines. It would be a conservative search, so it would follow *all* PP #ifdef branches unless it could prove that they shouldn't be followed. Wow, that sounds like an interesting but difficult dynamic programming problem. I wonder if it's even tractable?

I like Peter's idea much better in the near term ;-) -- Dave Abrahams Boost Consulting www.boost-consulting.com