BOOST_CLASS_VERSION emits use of old-style cast when compiling with -Wold-style-cast

[andre.kwakernaak@…]

In our project we want to compile all code with -Wold-style-cast and treat warnings as errors. We pass the boost/include directory with -isystem to gcc. This keeps warnings from boost from obfuscating our build output. However if a macro from constains warnings we still get them.

BOOST_CLASS_VERSION uses BOOST_MPL_ASSERT which causes the warning. I changed the old style casts to c++ casts in the macro's from boost/mpl/assert.hpp.

[andre.kwakernaak@…]

patch to change old style casts to c++ casts in mpl/assert.hpp

[Ulrich Eckhardt <ulrich.eckhardt@…>]

Two things:

1. That should be a static_cast, not a reinterpret_cast.
2. I wonder if instead of casting a null to an according function pointer type, it would be possible to tell assert_arg explicitly like assert_arg<void (*)(Pred)>(0, ...) and then rely on the conversion of 0 to the according type to do the right thing.