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Subject: Re: [boost] C++03 / C++11 compatibility question for compiled libraries
From: Paul A. Bristow (pbristow_at_[hidden])
Date: 2018-02-12 17:23:46

> -----Original Message-----
> From: Boost [mailto:boost-bounces_at_[hidden]] On Behalf Of Edward Diener via Boost
> Sent: 12 February 2018 04:27
> To: boost_at_[hidden]
> Cc: Edward Diener
> Subject: Re: [boost] C++03 / C++11 compatibility question for compiled libraries
> On 2/11/2018 6:46 PM, degski via Boost wrote:
> > On 11 February 2018 at 17:01, Edward Diener via Boost <boost_at_[hidden]
> >> wrote:
> OTOH I think you can encourage feature addition for a particular library
> but I do not think forcing some C++11 on up construct or library to be
> used is something that Boost ought to be doing.


Some on this thread seem to view 'support' and 'validated' as binary features.

Boost (and life in general) really isn't as simple as that.

Have you looked at the test matrix recently - there is plenty of 'not-green'.

Have you looked at the unfixed bugs'n'features list? There are plenty :-(

Tests done are a small subset of possible tests (they tend to infinity - for example a loopback test of double to decimal digits
string and back was found to take a lifetime for all possible 64-bit doubles).

There are lots of tests that pass on one compiler and fail on others.

So Boost (like everyone else) has always worked on a 'best-efforts' promise.

The tests are a guide to what works, but every user must 'suck it and see' and do additional tests in their environment for their
application for their risk tolerance.

If a library author is willing to provide a workaround for a pre-C++latest compiler, then users of that library should consider
themselves lucky. And if tests work with an obsolete compiler, then that's an ever bigger bonus too.

But having said that, Raffi's move to need C++11 compilers for Boost.Test should certainly focus *users* minds on the benefits of

(And he is managing it 'by the book' by raising the issue here now).

Getting all legalistic about what is 'supported' isn't going to help IMO.


Paul A. Bristow
Prizet Farmhouse
Kendal UK LA8 8AB
+44 (0) 1539 561830

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