On 4/6/2010 12:52 AM, Daniel James wrote:
I'll revert it for now but we should probably change config to define BOOST_NO_DECLTYPE for Visual C++ 10 if it's buggy on that compiler.
I had a similar thought. Here is the bug I filed against msvc: https://connect.microsoft.com/VisualStudio/feedback/details/548883 And for easy reference, here is the code: template<class T> struct S; template<class X, class Y> struct pair {}; template<class T> S<T> wrap(T) { return 0; } template<class T> struct S { S(int = 0) {} // The following use of decltype causes the compiler to blow up: decltype(wrap(pair<T,T>())) foo() { return wrap(pair<T,T>()); } // The following, which should be equivalent, compiles without // problem: //S<pair<T,T> > foo() { return wrap(pair<T,T>()); } }; int main() { S<int> s; } As you can see, decltype forces the types used in the expression to be complete. I'm not sure if that's conforming, but I hope not. I'd say it's premature to turn decltype on across the board for this compiler until we have a better idea of its limitations. The safe thing to do for 1.43 is to turn it off. We can always turn it on for 1.44. -- Eric Niebler BoostPro Computing http://www.boostpro.com