g++ on Windows: warning: converting to non-pointer type from NULL

[Fabian Meyer <mail@…>]

The following minimal program "error.cpp" generates the warning:

#include <boost/uuid/random_generator.hpp>

int main()
{
    boost::uuids::uuid id = boost::uuids::random_generator()();
}

Compiling on Windows (MinGW) with

g++ -I D:/libraries/boost_1_63_0/ error.cpp

yields the following message:

In file included from D:/libraries/boost_1_63_0/boost/uuid/random_generator.hpp:12:0,
                 from error.cpp:1:
D:/libraries/boost_1_63_0/boost/uuid/seed_rng.hpp: In constructor 'boost::uuids::detail::seed_rng::seed_rng()':
D:/libraries/boost_1_63_0/boost/uuid/seed_rng.hpp:96:23: warning: converting to non-pointer type 'boost::detail::winapi::HCRYPTPROV_ {aka long unsigned int}' from NULL [-Wconversion-null]
         , random_(NULL)
                       ^
D:/libraries/boost_1_63_0/boost/uuid/seed_rng.hpp:106:21: warning: converting to non-pointer type 'boost::detail::winapi::HCRYPTPROV_ {aka long unsigned int}' from NULL [-Wconversion-null]
             random_ = NULL;
                     ^

[James E. King, III <jking@…>]

PR submitted to resolve: ​https://github.com/boostorg/uuid/pull/18