-mlp64
(LP64 data model).
     -mle option selects little-endian
byte order (default) and -mbe selects big-endian byte order.  Note that
IA-64 machine code always uses little-endian byte order.
     -munwind-check=warning
will make the assembler issue a warning when an unwind directive check
fails.  This is the default.  -munwind-check=error will make the
assembler issue an error when an unwind directive check fails.
     -mhint.b=ok will make the assembler accept
hint.b.  -mint.b=warning will make the assembler issue a
warning when hint.b is used.  -mhint.b=error will make
the assembler treat hint.b as an error, which is the default.