On 11/9/2016 4:18 AM, David Laight wrote: > From: John Youn >> Sent: 08 November 2016 22:30 > ... >>>> Also make it __packed. >>> >>> why are you making it packed? Does it _have_ to be packed? If it must, >>> why wasn't it before? >> >> We want to guarantee that it reflects the exact descriptor structure >> in memory, so probably yes. It was overlooked before and worked >> because the compiler likely packed it anyways. This is just to make >> sure it does. > ... > > That isn't all that 'packed' means. > > 'packed' also tells the compiler to access the structure with instructions > that > will work if it isn't on the 'natural' boundary.
Good to know. > > If you want to ensure the structure is the right size (pretty pointless here) > then add a compile time assert against the structure size. Doesn't 'packed' make that unnecessary as well? Regards, John -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
