Detecting 64-bit Platforms

[Elliot Lee]

On Sun, 29 Aug 2004, Mike Barnes wrote:

> In reference to this:
> https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=122304
> 
> Just wondered if anyone had a good way to detect a 64-bit platform in
> the context of an RPM spec file. While building for the Alpha, we've
> come across similar situations a couple of times, where we turn up a
> bug that's already patched, but it's %ifarch-ed to x86_64 or whatever
> or, like in this case, just checking for "lib64" being used instead of
> "lib".
> 
> Aside from just manually updating ifarch lists for patches, is there
> any good way to just pull in a patch on any system that happens to be
> 64-bit?

Generally speaking, patches should be written so that the patched source
code compiles correctly on both 32-bit and 64-bit platforms. Patches that
are applied conditionally should be avoided at all cost. Doing this makes
it easier to add support for new platforms, makes it easier to merge the
patch upstream, and makes ongoing maintenance with the patch easier.

(BTW, some 64-bit platforms do not use multilib, so it's not clear whether
the idea is to check for multilib, or to check for actual 64-bitness).

Cheers,
-- Elliot
The daring is in the doing

http://people.redhat.com/sopwith/