X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fmath%2F__fpclassifyl.c;h=e41781b689af7f7db420fc437cc4a72e4dd00c33;hb=c5f4b2dfea320356f69445dc1adf8f73596a3c36;hp=481c0b949974ad43a59e95846bf9fb83ff5cbf23;hpb=3f92f92cb9c448ba82da5ff2cbbea692c7701c0c;p=musl diff --git a/src/math/__fpclassifyl.c b/src/math/__fpclassifyl.c index 481c0b94..e41781b6 100644 --- a/src/math/__fpclassifyl.c +++ b/src/math/__fpclassifyl.c @@ -13,10 +13,18 @@ int __fpclassifyl(long double x) int msb = u.i.m>>63; if (!e && !msb) return u.i.m ? FP_SUBNORMAL : FP_ZERO; + 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; + } if (!msb) return FP_NAN; - if (e == 0x7fff) - return u.i.m << 1 ? FP_NAN : FP_INFINITE; return FP_NORMAL; } #elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384