[GCC-XML] compilation pb running gccxml on code using SFINAE

[Brad King]

MOSS Sebastian wrote:
> Can you offer an insight as to why the difference in implementation is
> accepted by the earlier versions, compared with only the later versions
> of gcc with the mechanism I suggested?

I don't really know the internals of GCC's template instantiation code.
 I produced the alternative implementation by noting the error message
from gcc 3.3 about using an undefined type.  By moving the helper
template outside the main test template it was easier for the compiler
to realize the type was defined.

-Brad