Sorry, "Yz" constraint works just fine with ymm0. I needed just to delete "xmm0" from the "clobber" list ) -- View this message in context: http://gcc.1065356.n5.nabble.com/inline-asm-constraint-for-ymm0-register-analogous-to-Yz-for-xmm0-tp1096515p1096518.html Sent from the gcc - Help mailing list archive at Nabble.com.