Re: [Boost-users] [TR1] Configuration macros

From: John Maddock (john_at_[hidden])
Date: 2007-06-01 04:13:12

Scott Meyers wrote:
> Which is consistent with the "explicitly specify what your
> compiler/library support" idea above.  Unfortunately :-(

Right, but please remember that there is only one compiler that ships with 
*any* TR1 support at all - gcc - and that was still in the very early stages 
of development when Boost.TR1 was developed.  Given time it'll get smarter 
and "learn" about more compilers/platforms as they release TR1 support - if 
they do.

>> gcc: nothing if you're happy with the Boost versions,
>> BOOST_HAS_GCC_TR1 if you want to use the gcc-supplied versions.
>> It's possible that BOOST_HAS_GCC_TR1 is somewhat out of date, I
>> don't recall now which gcc version I tested with, but 4.2 probably
>> has more TR1 support than it currently enables.
>
> Which means that the macro doesn't mean "turn on whatever gcc TR1
> support you have," it means "turn on the following TR1 components
> that I, the macro writer, believe are supported by gcc." Again,
> consistent with the above.  And, again, unfortunately :-(
>
> I'd hoped that Boost.TR1 would magically figure out what TR1 stuff
> was available from my compiler/library and use that by default,
> falling back on Boost functionality only when necessary.  Apparently
> that is not the way it works :-(

Not yet :-(  As I say, it'll learn.

John.