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#undef __BYTE_ORDER
#ifdef BIG_endian
# define __BYTE_ORDER 1234
#endif
#ifdef LITTLE_endian
# define __BYTE_ORDER 4321
#endif
#if !(defined(__BYTE_ORDER))
#error "ieee754.h : you MUST specify \
-DBIG_endian or -DLITTLE_endian \
in CPPFLAGS of your Makefile."
/* Compiler must throw us out at this point! */
#endif
#define __BIG_ENDIAN 1234
#define __LITTLE_ENDIAN 4321
union ieee754_double
{
double d;
/* This is the IEEE 754 double-precision format. */
struct
{
#if __BYTE_ORDER == __BIG_ENDIAN
unsigned int negative:1;
unsigned int exponent:11;
/* Together these comprise the mantissa. */
unsigned int mantissa0:20;
unsigned int mantissa1:32;
#endif /* Big endian. */
#if __BYTE_ORDER == __LITTLE_ENDIAN
/* Together these comprise the mantissa. */
unsigned int mantissa1:32;
unsigned int mantissa0:20;
unsigned int exponent:11;
unsigned int negative:1;
#endif /* Little endian. */
} ieee;
/* This format makes it easier to see if a NaN is a signalling NaN. */
struct
{
#if __BYTE_ORDER == __BIG_ENDIAN
unsigned int negative:1;
unsigned int exponent:11;
unsigned int quiet_nan:1;
/* Together these comprise the mantissa. */
unsigned int mantissa0:19;
unsigned int mantissa1:32;
#else
/* Together these comprise the mantissa. */
unsigned int mantissa1:32;
unsigned int mantissa0:19;
unsigned int quiet_nan:1;
unsigned int exponent:11;
unsigned int negative:1;
#endif
} ieee_nan;
};
#define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */