Heyhey On Sun, Apr 12, 2015 at 08:56:40AM +0000, non...@inventati.org wrote: > On Sun, Apr 12, 2015 at 10:41:36AM +0200, Silvan Jegen wrote: > > I was thinking about this option too but in that case you would be > > calling memmove with an identical src and dst when i == 0. The man page > > for glibc memmove(3) does not mention anything about this being a noop > > so I am not sure that is a good thing to do. > > "The memory areas may overlap: copying takes place as though the bytes in > src are first copied into a temporary array that does not overlap src > or dest, and the bytes are then copied from the temporary array to dest." > > src == dest is just a case of overlapping areas, it must work.
I don't doubt that it will work :) I just wonder if it really will be copying the data around into a temporary array for no reason when i == 0 (either in glibc or in another libc). I don't think it is worth removing this if and potentially copying data around to no avail. At the same time I don't think this function is called very often so in practice it will not matter in either case. I just wanted to point it out so people can take it into consideration before deciding to apply your patches.
