On 20 Oct 2009, at 22:30, Jeff Trawick wrote:
On Tue, Oct 20, 2009 at 4:54 PM, Barry Scott <ba...@barrys-
emacs.org> wrote:
On 20 Oct 2009, at 04:18, Branko Čibej wrote:
Barry Scott wrote:
I think the problem is that configure is used to find out things
that
change arch to arch
like void * size rather then using preprocessor detection of those
things.
I wonder, how do you detect the size of void* with the
preprocessor in
C? The preprocessor doesn't understand sizeof.
You detect that its a build on mac os x and then use the CPU
feature macros
that the compiler defines to choose 4 or 8. You end up writing code
like
this:
#ifdef __APPLE__
#ifdef __x86_64__
its Mac intel 64
#endif
etc...
Testings for API functions being present would be arch independent.
That depends, doesn't it? There's no guarantee that you have the
same
external libraries available in several different flavours.
If you are talking about Mac OS X features then yes you have the
same libs
on all arch.
A vendor might provide an interface on a subset of architectures. A
vendor might have a architecture-specific bug in an interface used by
APR that would result in APR needing to disable its use for the
affected architecture build. I wouldn't bet that Apple is in a class
by itself with regards to these issues. (I recall that we had to
disable the use of some OS feature for 64-bit mode in the past, though
not on OS X.)
APR-util more obviously uses features that aren't OS features and are
packaged by groups with different philosophies. Maybe you only have
Oracle/MySQL/whatever client libraries for one architecture.
Indeed Apple might have a bug that you wish to work around by having
config detect the issue. But this is not the common case on the Mac as
far as I have experienced. (I only got bitten by an API being completely
missing on 10.4 power PC - very obvious as the code failed to build for
one arch.)
Why not consider having configure work in two modes:
A) As it does now, build one arch. This should be the default.
B) do a universal build with a list of arch of the users choosing
I have to explicitly choose this mode.
(B) means that the people that package for the Mac have a
greatly simplified life.
Barry
