gcc.dg/asm-b.c has #elif defined __i386__ || defined __x86_64__ __asm __volatile ("movb %b1,1(%2); movb %h1,(%2)" : "=m" (*z) : "r" (y), "r" (z)); #endif
The "r" constraint means any integer registers. But %b1/%h1 requires the "Q" constraint. -- Summary: Invalid x86 constraint in gcc.dg/asm-b.c Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: testsuite AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: hjl dot tools at gmail dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39451