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Re: About Universal Binaries...



Nick Zitzmann wrote: 

On Jan 31, 2006, at 6:06 PM, Juan P. Pertierra wrote:

From an initial look to the online Apple transition documentation it seems all the differences that have to be addressed span from the difference in byte order i.e. big endian vs little endian. 

That's one thing, but there's a lot more than that:

1. On PPC, if some code divides by zero, then the result returned is NaN and the executable will continue running. On Intel, if some code divides by zero, then the executable crashes.

This is not quite right.
For floating point, both processors generate inf for "x/0" where x>0, -inf for "x/0" where x<0, and NaN/ /for x=0 or NaN. These are just the regular IEEE floating point rules.
For integer, PowerPC generates 0 for any "x/0". Intel crashes with EXC_I386_DIV--this can be caught and handled in code, I think, but I haven't looked into it too much.

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References: 
 >Still struggling with Universal Binaries (From: Aram Kudurshian <email@hidden>)
 >Re: Still struggling with Universal Binaries (From: Shawn Erickson <email@hidden>)
 >About Universal Binaries... (From: "Juan P. Pertierra" <email@hidden>)
 >Re: About Universal Binaries... (From: Nick Zitzmann <email@hidden>)



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