Apple Mach-O链接器警告，在xcode上

Question

When ever I try to push my app to my ipad or ipod to test them I get this error...

alignment lost in merging tentative definition _resultbuffer.

What is it? Any idea how to fix it?

Answer 1

I'm going to take a wild guess here, apologies if I'm too far off the mark:

On the ARM processor alignment can be an issue, particularly if you're accessing a variables in an unaligned manner, I suspect this is what you're seeing:

Here's a couple links that might see you through this:

• gcc type-attributes documentation (Yes, I know its compiling with clang, this still may help)
• Basically the same thing from ARM's documentation
• A pretty good write-up about ARM alignment and how to avoid problems

Most flavors of ARM will automatically 'fix' this by adjusting the alignment on the fly, however this is configurable. The down-side is it causes a CPU interrupt to handle it, so if you're doing this over and over it'll slow things down. I haven't run into this on iOS, so I can't say for sure what the behavior would be. Odds are its best just to fix it.