As an extension, GNU C supports additional floating
types, __float80
and __float128
to support 80-bit
(XFmode
) and 128-bit (TFmode
) floating types.
Support for additional types includes the arithmetic operators:
add, subtract, multiply, divide; unary arithmetic operators;
relational operators; equality operators; and conversions to and from
integer and other floating types. Use a suffix ‘w’ or ‘W’
in a literal constant of type __float80
and ‘q’ or ‘Q’
for _float128
. You can declare complex types using the
corresponding internal complex type, XCmode
for __float80
type and TCmode
for __float128
type:
typedef _Complex float __attribute__((mode(TC))) _Complex128; typedef _Complex float __attribute__((mode(XC))) _Complex80;
Not all targets support additional floating-point types. __float80
and __float128
types are supported on i386, x86_64 and IA-64 targets.
The __float128
type is supported on hppa HP-UX targets.