Multiple compilation errors due to circular header inclusion dependency

[francisco.mailing.lists@…]

In file included from libs/math/build/../src/tr1/assoc_laguerre.cpp:10:

In file included from ./boost/math/tr1.hpp:383:

In file included from ./boost/math/tools/promotion.hpp:26:

In file included from ./boost/math/tools/config.hpp:25:

./boost/math/special_functions/detail/round_fwd.hpp:24:13: error: use of undeclared identifier 'tools'

typename tools::promote_args<T>::type trunc(const T& v, const Policy& pol);

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promotion includes config, config includes round_fwd, round_fwd includes promotion.

config.h seems to not need to include round_fwd.h, since from what I've checked, what it used from round_fwd.h is inside a definition of a macro (BOOST_MATH_STD_USING), hence no compile time dependency.

[anonymous]

Well, just removing the include from config.h wont solve either (as expected).

[francisco.mailing.lists@…]

I've not thought it throughout, the include guards should prevent this, I'm using clang... not sure where the problem may lie anymore.

[francisco.mailing.lists@…]

oh yeah, promotion.h includes config.h on on top, config.h includes round_fwd.hpp, round_fwd.hpp includes promotion.h, which includes nothing because of the guards of the first inclusion, and them goes on using declaration from promotion.h which is still not expanded.

[John Maddock]

(In [82921]) Fix cyclic dependency. Fixes #7999.