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authorMark H Weaver <mhw@netris.org>2014-02-03 21:04:39 -0500
committerMark H Weaver <mhw@netris.org>2014-02-03 21:05:52 -0500
commit5e69ceb7a667377a61cb0c31d7ac20e245b3fafd (patch)
treeef1e4fe569392fd4630dfcfc26d9948b7e6ffac5 /lib/isnan.c
parent866af5da3d11ac4a9df44ee8c5b1781a0073c288 (diff)
Update Gnulib to v0.1-77-gd9361da
Diffstat (limited to 'lib/isnan.c')
-rw-r--r--lib/isnan.c20
1 files changed, 16 insertions, 4 deletions
diff --git a/lib/isnan.c b/lib/isnan.c
index 18fa5a2ec..1557733bf 100644
--- a/lib/isnan.c
+++ b/lib/isnan.c
@@ -1,5 +1,5 @@
/* Test for NaN that does not need libm.
- Copyright (C) 2007-2013 Free Software Foundation, Inc.
+ Copyright (C) 2007-2014 Free Software Foundation, Inc.
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
@@ -79,10 +79,21 @@ extern int rpl_isnanf (float x);
((sizeof (DOUBLE) + sizeof (unsigned int) - 1) / sizeof (unsigned int))
typedef union { DOUBLE value; unsigned int word[NWORDS]; } memory_double;
+/* Most hosts nowadays use IEEE floating point, so they use IEC 60559
+ representations, have infinities and NaNs, and do not trap on
+ exceptions. Define IEEE_FLOATING_POINT if this host is one of the
+ typical ones. The C11 macro __STDC_IEC_559__ is close to what is
+ wanted here, but is not quite right because this file does not require
+ all the features of C11 Annex F (and does not require C11 at all,
+ for that matter). */
+
+#define IEEE_FLOATING_POINT (FLT_RADIX == 2 && FLT_MANT_DIG == 24 \
+ && FLT_MIN_EXP == -125 && FLT_MAX_EXP == 128)
+
int
FUNC (DOUBLE x)
{
-#ifdef KNOWN_EXPBIT0_LOCATION
+#if defined KNOWN_EXPBIT0_LOCATION && IEEE_FLOATING_POINT
# 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
/* Special CPU dependent code is needed to treat bit patterns outside the
IEEE 754 specification (such as Pseudo-NaNs, Pseudo-Infinities,
@@ -153,8 +164,9 @@ FUNC (DOUBLE x)
}
# endif
#else
- /* The configuration did not find sufficient information. Give up about
- the signaling NaNs, handle only the quiet NaNs. */
+ /* The configuration did not find sufficient information, or does
+ not use IEEE floating point. Give up about the signaling NaNs;
+ handle only the quiet NaNs. */
if (x == 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