Re: [Boost-users] 1.57.0 beta 1 release candidates available for testing

Subject: Re: [Boost-users] 1.57.0 beta 1 release candidates available for testing
From: John Maddock (boost.regex_at_[hidden])
Date: 2014-10-19 13:04:02

> Visual C++ 14 CTP 4 with BOOST_MSVC_ENABLE_2014_JUN_CTP: compile errors in
> Graph and Log because of is_nothrow_move_assignable in TypeTraits

OK, I managed to get CTP4 installed and have 2 updates:

For Boost.Config: 
https://github.com/boostorg/config/commit/d9026f1d45f28947024a3f2d393e138ff1db6a68 
a mostly minor update.

For TypeTraits: 
https://github.com/boostorg/type_traits/commit/5c0474dbc7d6ed28bacf64348139814d13bd8097

I suspect you're not going to like the latter as it basically disables 
working versions of is_nothrow* for msvc-14.  The reason is that is 
appears that Boost.Log ends up using noexcept(non_compiling_expression) 
which requires SFINAE expression support.

I'm not sure about this though because the error messages from the 
Boost.Log failed build are pretty inscrutable - they refer to 
boost::spirit::info being undefined when it clearly is, and also the 
instantiation backtrace goes nowhere, so I suspect a compiler bug and/or 
noexcept being too immature on this compiler for serious use.

I'll double check MSVC-14 noexcept support with the multiprecision tests 
as they make quite a bit of use of this.  Any other libraries?

One final question - to what extent should we try to support this 
compiler in 1.57 given that it's still in alpha?

John.