Re: [libvirt] [PATCH 4/9] xen: Add coverity[ptr_arith] and [sign_extension] tags

>> Mathematically what you propose with the memcpy() works; however, I come >> from an architecture where a memcpy to an unaligned address causes a >> fault > > Such a memcpy() implementation would be flawed, and should be reported > as a bug to that vendor; thankfully, these days, most libc do not have > that flaw. The C standard guarantees that memcpy() is required to work > on unaligned copies (for a certain definition of work; you may still end > up splicing together unrelated portions of adjacent integers when > reading things back as integers, but byte-for-byte, the operation is > well-defined). > Alpha and Itanium have some (silent unless noise enabled) heartache when the "to" address is "0x7ffe8f2b8cf1" (or x2, x3, x5, x6, x7, etc). Ending with x0 & x8 are preferred while x4 & xc tolerated. If the noise isn't turned on, the application performs poorly due to excessive alignment faults.