long double format on I!64

[Steve Ellcey]

>     // While sizeof(long double) == 16, the format is the same as the x86.
>     #define __glibcpp_long_double_bits 80

FYI:  While Linux on IA64 uses the 80 bit format, HP-UX does not.  It
uses the full 128 bit format for long double.  In gcc/config/ia64 the
floating point format is determined by the macro
INTEL_EXTENDED_IEEE_FORMAT.  (1 for 80 bit format, 0 for 128 bit
format).  This is because the HP-UX C and C++ compilers also use 128
bits for long double in order to be compatible with the HP-UX PA
compilers.

Steve Ellcey
sje@cup.hp.com