From e7aa772fe7a5db390955f25312f4068dd8a7527d Mon Sep 17 00:00:00 2001
From: Keith Packard via Newlib <newlib@sourceware.org>
Date: Wed, 25 Mar 2020 17:18:19 -0700
Subject: [PATCH] newlib/libm/common: Fix modf/modff returning snan
Recent GCC appears to elide multiplication by 1, which causes snan
parameters to be returned unchanged through *iptr. Use the existing
conversion of snan to qnan to also set the correct result in *iptr
instead.
Signed-off-by: Keith Packard <keithp@keithp.com>
---
newlib/libm/common/s_modf.c | 10 ++--------
newlib/libm/common/sf_modf.c | 10 ++--------
2 files changed, 4 insertions(+), 16 deletions(-)
diff --git a/newlib/libm/common/s_modf.c b/newlib/libm/common/s_modf.c
index c948b8525..c826580b4 100644
--- a/newlib/libm/common/s_modf.c
+++ b/newlib/libm/common/s_modf.c
@@ -63,12 +63,6 @@ QUICKREF
#ifndef _DOUBLE_IS_32BITS
-#ifdef __STDC__
-static const double one = 1.0;
-#else
-static double one = 1.0;
-#endif
-
#ifdef __STDC__
double modf(double x, double *iptr)
#else
@@ -99,8 +93,8 @@ static double one = 1.0;
}
} else if (j0>51) { /* no fraction part */
__uint32_t high;
- *iptr = x*one;
- if (__fpclassifyd(x) == FP_NAN) return x+x; /* x is NaN, return NaN */
+ *iptr = x;
+ if (__fpclassifyd(x) == FP_NAN) return *iptr = x+x; /* x is NaN, return NaN */
GET_HIGH_WORD(high,x);
INSERT_WORDS(x,high&0x80000000,0); /* return +-0 */
return x;
diff --git a/newlib/libm/common/sf_modf.c b/newlib/libm/common/sf_modf.c
index ae970762b..e241e4612 100644
--- a/newlib/libm/common/sf_modf.c
+++ b/newlib/libm/common/sf_modf.c
@@ -15,12 +15,6 @@
#include "fdlibm.h"
-#ifdef __STDC__
-static const float one = 1.0;
-#else
-static float one = 1.0;
-#endif
-
#ifdef __STDC__
float modff(float x, float *iptr)
#else
@@ -51,8 +45,8 @@ static float one = 1.0;
}
} else { /* no fraction part */
__uint32_t ix;
- *iptr = x*one;
- if (__fpclassifyf(x) == FP_NAN) return x+x; /* x is NaN, return NaN */
+ *iptr = x;
+ if (__fpclassifyf(x) == FP_NAN) return *iptr = x+x; /* x is NaN, return NaN */
GET_FLOAT_WORD(ix,x);
SET_FLOAT_WORD(x,ix&0x80000000); /* return +-0 */
return x;