From: Phil Richards (news_at_[hidden])
Date: 2006-10-19 15:21:39
On 2006-10-18, John Maddock <john_at_[hidden]> wrote:
> Markus Schöpflin wrote:
> > John Maddock wrote:
> > Hmm, I think this is completely beyond me. I can't even find where
> > that cast to int comes from. Here is the preprocessed source code for
> > reference:
> Hmm, I managed to find a copy of gcc-4.1 to test with, and this completely
> perplexes me too. In fact I can't find *anything* in the mpl sources or
> tests that look like the code in the error message!
I'm pretty sure it's a compiler bug. The code in question is below
(with my little bit added):
template< typename T >
void count_test()
{
#if DEFINE_THIS_TO_MAKE_THE_TEST_COMPILE
enum { v1 = count<typename T::s0,int>::value };
enum { v2 = count<typename T::s1,int>::value };
enum { v3 = count<typename T::s2,int>::value };
enum { v4 = count<typename T::s2,char&>::value };
enum { v5 = count<typename T::s3,int>::value };
enum { v6 = count<typename T::s3,char&>::value };
enum { v7 = count<typename T::s4,abstract>::value };
#endif
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s0,int>::value ), ==, 0 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s1,int>::value ), ==, 1 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s2,int>::value ), ==, 1 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s2,char&>::value ), ==, 1 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s3,int>::value ), ==, 2 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s3,char&>::value ), ==, 1 );
MPL_ASSERT_RELATION( ( count<BOOST_DEDUCED_TYPENAME T::s4,abstract>::value ), ==, 1 );
}
If you enable the #if'd code, then the test compiles fine; if
you don't then you get that strange error. It shouldn't, of course,
make any difference...
phil
-- change name before "@" to "phil" for email