Re: [boost] [config] polygon library long long, long double portability

Subject: Re: [boost] [config] polygon library long long, long double portability
From: John Maddock (john_at_[hidden])
Date: 2009-06-26 04:23:33

>> msvc has 64 bit ints, but doesn't call them long long.

Yes it does, at least with current versions :-)

>>
> Yes, I realized that long double must be standard after grepping the boost 
> codebase and seeing it used everywhere.  If we searched the archive we'd 
> probably find I asked this same question in the past.  I might be a slow 
> learner.  My code with long long compiles in MSVC, does is compile to a 32 
> bit int?  Specifying int64_t would make sense if my integer coordinate 
> traits were in terms of int32_t, but they are in terms of int.  Perhaps I 
> should change that as well.

Please don't confuse types, with widths: you need to use either specific 
width types throughout (which are all of unspecified type), or use specific 
types.  For example code that needs to overload a function for all the 
integer *types* would use long long where available, where as code that's 
designed to work with specific *widths* should use the boost::intXX_t types 
throughout, in the knowledge that these may not cover all the available 
*types* (for example if long is a 64-bit int then long long is never used by 
the intXX_t typedefs).

I hope that's not too confusing :-)  Basically decide which set to used 
based on what your code does, and what the integers represent.

HTH, John.