Re: [boost] The future and present of Boost

Subject: Re: [boost] The future and present of Boost
From: Peter Dimov (lists_at_[hidden])
Date: 2018-10-24 21:21:13

Edward Diener wrote:
> I don't get this. Why can't library X, which needs C++11, depend on 
> library Y, which needs C++03 but works fine if compiled with C++11. What 
> am I missing here ?

I don't know how to answer this, and I don't know how it relates to what I 
was saying.

What I was saying is this: the user, or someone acting on his behalf such as 
a package maintainer, types f.ex.

    b2 toolset=clang install

and obtains a prebuilt Boost.

Then the user types f.ex.

    clang++ -std=c++17 myapp.cpp -lboost_pumpkin

and expects it to work. If boost_pumpkin autodetects C++11/C++14/C++17 and 
changes its API to match, it doesn't work.

It doesn't because step 1 builds libboost_pumpkin.a with the 
default -std=c++03.

Same with g++ 5.

Not same with g++ 6 and above, whose default is C++14, but still possible if 
the library adapts to C++17 by using f.ex. <filesystem>.