The following code stopped working with gcc-4.5.
gcc-4.4.3 and clang both accept it.
On gcc-4.5, boost::mpl_::arg<2> is passed to metafunction instead of test1.
The strange thing is: If the specialization of metafunction<_2> is provided,
the code works again.
I'm sorry that this is not a minimal test case, because I don't know how to get
rid of the MPL parts.
#include <boost/mpl/placeholders.hpp>
#include <boost/mpl/fold.hpp>
#include <boost/mpl/push_back.hpp>
#include <boost/mpl/at.hpp>
#include <boost/mpl/vector/vector10.hpp>
struct test1
{
typedef int inner_type;
};
template<
typename Foo
>
struct metafunction
{
typedef typename Foo::inner_type type;
};
#if 0
template<>
struct metafunction<
boost::mpl::_2
>;
#endif
int main()
{
typedef boost::mpl::fold<
boost::mpl::vector1<
test1
>,
boost::mpl::vector0<>,
boost::mpl::push_back<
boost::mpl::_1,
metafunction<
boost::mpl::_2
>
>
>::type transformed;
boost::mpl::at_c<transformed, 0>::type i = 42;
}
--
Summary: Boost.MPL code doesn't get the placeholders substituted
anymore
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: sefi at s-e-f-i dot de
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43608
