Re: [boost] [clang][preprocessor] Testing of clang emualting the VC++ preprocessor on Windows

Subject: Re: [boost] [clang][preprocessor] Testing of clang emualting the VC++ preprocessor on Windows
From: Paul Mensonides (pmenso57_at_[hidden])
Date: 2016-03-31 18:35:57

On 3/30/2016 5:22 PM, Gavin Lambert wrote:
> On 31/03/2016 12:56, Edward Diener wrote:

>> Asking programmers to support another broken C++ preprocessor at this
>> stage of C++'s development history is a travesty. And all simply because
>> Microsoft has refused for a quarter of a century to fix their C++
>> preprocessor implementation, which they well know has always been
>> non-standard.

Yes.

> Presumably they both have the same motivations: trillions (or likely
> much higher) of lines of existing code, some unknown fraction of which
> might depend on the quirks of the existing behaviour.

The current state of C++ is a many-to-many-to-many scenario:

compilers x platforms x codebases x { standard }

An ideal state would be many-to-one scenario:

(compilers U platforms U code) x { standard }

With the size of these sets growing, the latter is a scalable model; the 
former is not.

While an ideal state may only be achievable in the limit, we should be 
moving in that direction--not intentionally away from it.  If we do 
continue to move in that direction (which we must or C++ will die), the 
aforementioned code must break at some point.  With the sets growing, 
the sooner it breaks the better because it just gets worse as time goes on.

> Bear in mind that one of clang's goals is not just to compile new
> portable programs but also existing previously-MSVC-only codebases, with
> minimal (or no) changes to the code.

Yes, a misguided goal and deplorable mentality.  Valuing popularity more 
highly that doing what is right results in trading future productivity 
for short-term expediency.  This is an ethical rather than technical 
failure and a disservice to most of the current generation of C++ 
developers and all of their successors.  Shame on them.

Regards,
Paul Mensonides