> On 11 Mar 2015, at 18:13, Jonas Maebe <[email protected]> wrote: > > > On 06 Mar 2015, at 02:50, Jens Alfke wrote: > >> Shouldn’t C alignment rules dictate that the ‘value’ union and the >> surrounding ‘atomic_val_t’ type be 8-byte-aligned, since they contain a >> 64-bit integer? > > Alignment rules are not dictated by the programming language, but by the ABI. > The ARM ABI, and also Apple's variant, says that 64 bit integers are only > guaranteed 4 byte alignment: > https://developer.apple.com/library/ios/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARMv6FunctionCallingConventions.html >
If that's true, and read it too, the the compiler shouldn't be emitting a double word load which requires 8-byte alignment on a platform which doesn't guarantee it. _______________________________________________ Do not post admin requests to the list. They will be ignored. Xcode-users mailing list ([email protected]) Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/xcode-users/archive%40mail-archive.com This email sent to [email protected]
