Messages in this thread | | | Date | Wed, 14 Mar 2012 16:33:51 -0700 | From | Derek Fawcus <> | Subject | Re: [tip:x86/x32] x32: Fix alignment fail in struct compat_siginfo |
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On Wed, Mar 14, 2012 at 04:17:29PM -0700, H.J. Lu wrote: > Just for the record, although the offsets of _utime and _stime are > multiple of 8 bytes, struct siginfo is only aligned at 4 bytes. So > the addresses of _utime and _stime may not be 8byte aligned. > But misaligned int64 load/store are OK for x86-64.
So whereas on i386 and x86_64 we can set eflags.AC (or rflags.AC) to test the code for aligment safeness, we'll not be able to do so with x32?
(Simply 'cause this could get false positive on syscalls).
Granted this is not a common use, but I've done it for checking that code will easily port to ppc/mips.
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