id summary reporter owner description type status milestone component version severity resolution keywords cc 4526 [MSVC 10 & 9 & 8] forward declarations of concept checked function templates don't work (compiler bug?) Stefan van Kessel jsiek "As posted by Lorenzo Caminiti to comp.lib.boost.devel (8/9/2010) forward declarations of concept checked function templates lead to ambiguity errors even though the function signatures are identical when compiled with MSVC (I tested MSVC 10 & MSVC9, Caminit MSVC8) I believe it boils down to a compiler error where MSVC fails to recognize that signatures are identical when the return type depends on fairly complex expressions that include non type template arguments. I've got a patch that seems to work for MSVC10. Since I used decltype it doesn't help for the older versions though. I haven't tested it much and I'm sure I'm breaking all kinds of boost coding guidelines but maybe it's of help anyway. " Bugs new Boost 1.44.0 concept_check Boost 1.43.0 Problem concept_check forward-declaration