[Zlib-devel] zlib large file support

[Mark Brown]

On Fri, Dec 31, 2004 at 08:35:43AM -0700, Nelson H. F. Beebe wrote:

> Mark Adler <madler at alumni.caltech.edu> asks about compilation of zlib
> on various systems to enable access to 64-bit file offsets.

> There are two approaches: build the library in a 32-bit world with
> 64-bit file offsets, or build the library in a 64-bit world.

> The GNU/Linux systems on MIPS, PowerPC, and SPARC fail to provide
> access to a 64-bit world, even though the hardware supports it.

You can build a 64 bit userland for at least SPARC (and I suspect
others), it's just not generally done since it's not considered worth
it.  Debian, for example, does ship 64 bit builds of the core libraries
(including zlib) and some utilities but as with Solaris almost all of
userspace is 32 bit.  The wins from wider registers tend not to be
noticeable, especially considering things like cache footprint increases
that can also happen.

If -m32 and -m64 are being supported I'd suggest testing for them always
- it's marginally more future proof and will cope with oddball
situations where the default compiler isn't the one you'd expect for the
architecture.

-- 
"You grabbed my hand and we fell into it, like a daydream - or a fever."