The ia64 backend has various undocumented machine attributes. Unfortunately they are used in code.
{ "syscall_linkage", 0, 0, false, true, true, NULL }, { "model", 1, 1, true, false, false, ia64_handle_model_attribute }, { "version_id", 1, 1, true, false, false, ia64_handle_version_id_attribute }, Would be good to document them. -- Summary: undocumented attributes on ia64 Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: target AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: ak at muc dot de GCC target triplet: ia64-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30687