LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
October 2007
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2007.10.23 16:12 "Re: universal build patch", by Bob Friesenhahn
On Tue, 23 Oct 2007, Andrey Kiselev wrote: > > We can easily switch to this method instead of autoconf macro. I am only > concerning about portability of this approach. It is 100% portable as long as you stick to using Apple's modified GCC 4.X and OS X. Other targets are of no consequence. :-) Solaris defines _LITTLE_ENDIAN or _BIG_ENDIAN by including <sys/types.h> OS X (and probably *BSD) define BIG_ENDIAN, LITTLE_ENDIAN and BYTE_ORDER but don't define __BIG_ENDIAN, __LITTLE_ENDIAN nor __BYTE_ORDER Apple's gcc for ppc-darwin has a built-in define of __BIG_ENDIAN__ as 1, but doesn't define __LITTLE_ENDIAN__ nor __BYTE_ORDER. Linux glibc headers define both BIG_ENDIAN and __BIG_ENDIAN, LITTLE_ENDIAN and __LITTLE_ENDIAN, and __BYTE_ORDER and BYTE_ORDER System FOO does whatever it feels like. My feeling is that it the only completely correct approach is to configure/build on each native target since otherwise some decisions made may be wrong. Perhaps 32-bit OS X has managed to constrain PPC and Intel differences to only endian order but this is the exception rather than the rule. With Mac OS X Leopard (Arriving October 26) perhaps the rules will change (the rules for Apple always change). Bob ====================================== Bob Friesenhahn bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/