+ if (e == 0x7fff) {
+ /* The x86 variant of 80-bit extended precision only admits
+ * one representation of each infinity, with the mantissa msb
+ * necessarily set. The version with it clear is invalid/nan.
+ * The m68k variant, however, allows either, and tooling uses
+ * the version with it clear. */
+ if (__BYTE_ORDER == __LITTLE_ENDIAN && !msb)
+ return FP_NAN;
+ return u.i.m << 1 ? FP_NAN : FP_INFINITE;
+ }