The ia64-hpux version of GCC supports several options that don't appear
to be documented. I see at least the following:
-milp32
-mlp64
-mt
--
Summary: undocumented ia64-hpux options
Product: gcc
Version: 3.4.1
Status: UNCONFIRMED
Severity: minor
Priority: P2
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: jweening at ccrwest dot org
CC: gcc-bugs at gcc dot gnu dot org
GCC build triplet: ia64-hp-hpux11.23
GCC host triplet: ia64-hp-hpux11.23
GCC target triplet: ia64-hp-hpux11.23
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18027