On Mon, Jun 08, 2020 at 10:49:22PM +0900, Oleg Endo wrote: > On Mon, 2020-06-08 at 15:34 +0200, Lars Poeschel wrote: > > > > What am I missing ? What am I doing wrong ? > > > > You're casting an address of some byte array to a point to struct, > which has an alignment > 1 byte. Try adding a #pragma pack (1) or > respective attribute. Thank you! The pragma does indeed the right thing. gcc now produces code, that accesses the fields in question individually. But shouldn't the option -mno-unaligned-access I use for compiling also do the same ? Why is this not working ? Thanks again, Lars