Re: [boost] [mpl] Abandoning old compilers

Subject: Re: [boost] [mpl] Abandoning old compilers
From: John Maddock (jz.maddock_at_[hidden])
Date: 2015-02-28 13:58:25

On 28/02/2015 18:43, Peter Dimov wrote:
> Edward Diener wrote:
>> No. It never was tested. It was reverted before any testing was done 
>> on the 'develop' branch with those changes.
>
> I'm not sure that lack of testing on current compilers is the main 
> issue. The main issue is "lack of consensus" for dropping support for 
> old compilers, which aren't tested.
>
> I'll say again what I always say when this issue comes up: these 
> compilers are old. They are unlikely to be able to compile new Boost 
> libraries. People who use these compilers can just use older Boost 
> releases (and are probably forced to anyway).
>
> We should drop VC++6/7, bcc32, dmc, old sun support from MPL to make 
> it more maintainable - provided that it is going to be maintained at 
> all, or course.
>

+1

Requiring a compiler under 10 years old isn't such a stretch, and as you 
say new code is written for new compilers anyway... plus the old code is 
never tested on old compilers so is likely to be broken in strange and 
surprising ways (by dependencies breaking, if not patches to the library 
in question).

Aside: I believe the original changes were reverted for a number of 
reasons, but a lack of consensus was certainly one ("don't rip apart 
some elses library without due process" etc).  They possibly did both 
too little and too much as well - dropping support for old compilers 
without really properly cleaning up and modernising the code (which 
would be a lot of work).  Or to put it another way - if you're going to 
change such a core library, then the gains had better be big ones, 
otherwise best leave alone.

John.