On Mar 16, 2010, at 3:50 PM, H.J. Lu wrote: > 2010/3/8 Paweł Sikora <pl...@agmk.net>: >> hi, >> >> during development a cross platform appliacation on x86 workstation >> i've enabled an alignemnt checking [1] to catch possible erroneous >> code before it appears on client's sparc/arm cpu with sigbus ;) >> >> it works pretty fine and catches alignment violations but Jakub Jelinek >> had told me (on glibc bugzilla) that gcc on x86 can still dereference >> an unaligned pointer (except for vector insns). >> i suppose it means that gcc can emit e.g. movl for access a short int >> (or maybe others scenarios) in some cases and violates cpu alignment rules. >> >> so, is it possible to instruct gcc-x86 to always use suitable loads/stores >> like on sparc/arm? >> >> [1] "AC" bit - http://en.wikipedia.org/wiki/FLAGS_register_(computing) >> > > I am interested in an -mstrict-alignment option for x86.
Not sure it will be useful. The libc still does unaligned accesses IIRC.
