Option -mno-fused-madd is currently not supported on IA-64. This means that the expression x*y+z is always fused (IA-64's fma instruction) and this cannot be disabled, unlike on PowerPC.
BTW, I wonder why this option exists for PowerPC (and other CPU types) but not for IA-64. Isn't it similar, or is there some difficulty? -- Summary: Option -mno-fused-madd should be supported on IA-64 Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: enhancement Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: vincent at vinc17 dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37846