Re: breaking compatibility

[Phil Edwards <pedwards at disaster dot jaj dot com>]

On Thu, Apr 19, 2001 at 01:11:29PM -0700, Loren Osborn wrote:
> The biggest concern here is that the project still has to build in Visual
> Studio (MS Visual C++) :( ... Visual still uses pretty separate *.h headers
> from the new extentionless headers... and they don't mix well... we have, in
> the past, tried switching to the new ISO extensionless headers, but we
> encountered some real problems...

You're in trouble.  VC6 is so non-compliant with the standard that nobody
I know uses it.  For Windows programming their companies have all moved to
compilers from Borland or IBM or Comeau.  Granted that version 6 predated
the final publication of the standard, but none of the subsequent patches
have done much of anything towards standard compliance.

If you want an idea of just how much lossage you're looking at, check out
the config header from Boost.  They assume the compiler is ISO-compliant,
and then the config header provides workarounds for those that aren't.
About half the header is devoted to VC6, turning off useful features that
the compiler itself (not just the library) implements incorrectly.

It's not a question of "gcc" really.  It's a question of "ISO Standard C++".
You can either write standard code, or you can use VC6.  You'd have the
same difficulties trying to use any other recent compiler.


> If you can think of a way to get this working with visual
> *AND* gcc without requiring us to change several thousand lines of code this
> would be best for us...

Many people have reported good results using STLport 4.x from stlport.org.

Dinkumware implemented the STL that shipped with VC6.  They sell an updated
and corrected implementation for VC6 on their website.  It's reported to
be very good, given the compiler lossage it has to work with, but I've no
experience with it myself.

The microsoft.public.* newsgroups have more in their FAQs.  The question
of standard-vs-VC6 is a common one and you are not the first to be hit by it.


Phil

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