diff options
Diffstat (limited to 'lib/isnan.c')
| -rw-r--r-- | lib/isnan.c | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/lib/isnan.c b/lib/isnan.c index 915187ba..491dc6dc 100644 --- a/lib/isnan.c +++ b/lib/isnan.c @@ -1,5 +1,5 @@ /* Test for NaN that does not need libm. - Copyright (C) 2007-2025 Free Software Foundation, Inc. + Copyright (C) 2007-2026 Free Software Foundation, Inc. This file is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as @@ -105,10 +105,8 @@ FUNC (DOUBLE x) The NaN bit pattern is: - exponent = 0x7FFF, mantissa >= 0x8000000000000001. */ memory_double m; - unsigned int exponent; - m.value = x; - exponent = (m.word[EXPBIT0_WORD] >> EXPBIT0_BIT) & EXP_MASK; + unsigned int exponent = (m.word[EXPBIT0_WORD] >> EXPBIT0_BIT) & EXP_MASK; # ifdef WORDS_BIGENDIAN /* Big endian: EXPBIT0_WORD = 0, EXPBIT0_BIT = 16. */ if (exponent == 0) @@ -138,9 +136,9 @@ FUNC (DOUBLE x) Visual C/C++ compiler also fails when constant-folding 1.0 / 0.0 even when constant-folding is not required. */ static DOUBLE zero = L_(0.0); - memory_double nan; DOUBLE plus_inf = L_(1.0) / zero; DOUBLE minus_inf = -L_(1.0) / zero; + memory_double nan; nan.value = zero / zero; # else static memory_double nan = { L_(0.0) / L_(0.0) }; @@ -149,10 +147,10 @@ FUNC (DOUBLE x) # endif { memory_double m; + m.value = x; /* A NaN can be recognized through its exponent. But exclude +Infinity and -Infinity, which have the same exponent. */ - m.value = x; if (((m.word[EXPBIT0_WORD] ^ nan.word[EXPBIT0_WORD]) & (EXP_MASK << EXPBIT0_BIT)) == 0) @@ -171,12 +169,13 @@ FUNC (DOUBLE x) # if defined USE_LONG_DOUBLE && ((defined __ia64 && LDBL_MANT_DIG == 64) || (defined __x86_64__ || defined __amd64__) || (defined __i386 || defined __i386__ || defined _I386 || defined _M_IX86 || defined _X86_)) && !HAVE_SAME_LONG_DOUBLE_AS_DOUBLE /* Detect any special bit patterns that pass ==; see comment above. */ memory_double m1; - memory_double m2; - memset (&m1.value, 0, SIZE); - memset (&m2.value, 0, SIZE); m1.value = x; + + memory_double m2; + memset (&m2.value, 0, SIZE); m2.value = x + (x ? 0.0L : -0.0L); + if (!memeq (&m1.value, &m2.value, SIZE)) return 1; # endif |