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authorStefan Liebler <stli@linux.vnet.ibm.com>2014-04-29 15:43:36 +0200
committerAndreas Krebbel <krebbel@linux.vnet.ibm.com>2014-04-29 15:43:36 +0200
commit2ca180e97a16f3ee3ec9e7e5a5fb7eda3d863a02 (patch)
tree4b1d6f28281ad75b3abe35ee09684e1aae943012
parentdc041bd4dbaf0f22b962647e0d0a1b8090d0e679 (diff)
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[BZ #16823] Fix log1pl returning wrong infinity sign
-rw-r--r--ChangeLog8
-rw-r--r--sysdeps/ieee754/dbl-64/s_log1p.c2
-rw-r--r--sysdeps/ieee754/flt-32/s_log1pf.c2
-rw-r--r--sysdeps/ieee754/ldbl-128/s_log1pl.c2
4 files changed, 11 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog
index 4007295..803d114 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2014-04-29 Stefan Liebler <stli@linux.vnet.ibm.com>
+
+ [BZ #16823]
+ * sysdeps/ieee754/ldbl-128/s_log1pl.c (__log1pl):
+ Always divide by positive zero when computing -Inf result.
+ * sysdeps/ieee754/dbl-64/s_log1p.c (__log1p): Likewise.
+ * sysdeps/ieee754/flt-32/s_log1pf.c (__log1pf): Likewise.
+
2014-04-28 Adhemerval Zanella <azanella@linux.vnet.ibm.com>
* sysdeps/powerpc/fpu/fclrexcpt.c (__feclearexcept): Do not update
diff --git a/sysdeps/ieee754/dbl-64/s_log1p.c b/sysdeps/ieee754/dbl-64/s_log1p.c
index fd4dce5..c922148 100644
--- a/sysdeps/ieee754/dbl-64/s_log1p.c
+++ b/sysdeps/ieee754/dbl-64/s_log1p.c
@@ -110,7 +110,7 @@ __log1p (double x)
if (__glibc_unlikely (ax >= 0x3ff00000)) /* x <= -1.0 */
{
if (x == -1.0)
- return -two54 / (x - x); /* log1p(-1)=+inf */
+ return -two54 / zero; /* log1p(-1)=-inf */
else
return (x - x) / (x - x); /* log1p(x<-1)=NaN */
}
diff --git a/sysdeps/ieee754/flt-32/s_log1pf.c b/sysdeps/ieee754/flt-32/s_log1pf.c
index 0307277..5f00feb 100644
--- a/sysdeps/ieee754/flt-32/s_log1pf.c
+++ b/sysdeps/ieee754/flt-32/s_log1pf.c
@@ -42,7 +42,7 @@ __log1pf(float x)
k = 1;
if (hx < 0x3ed413d7) { /* x < 0.41422 */
if(ax>=0x3f800000) { /* x <= -1.0 */
- if(x==(float)-1.0) return -two25/(x-x); /* log1p(-1)=+inf */
+ if(x==(float)-1.0) return -two25/zero; /* log1p(-1)=-inf */
else return (x-x)/(x-x); /* log1p(x<-1)=NaN */
}
if(ax<0x31000000) { /* |x| < 2**-29 */
diff --git a/sysdeps/ieee754/ldbl-128/s_log1pl.c b/sysdeps/ieee754/ldbl-128/s_log1pl.c
index d991e8a..d8d89f0 100644
--- a/sysdeps/ieee754/ldbl-128/s_log1pl.c
+++ b/sysdeps/ieee754/ldbl-128/s_log1pl.c
@@ -150,7 +150,7 @@ __log1pl (long double xm1)
if (x <= 0.0L)
{
if (x == 0.0L)
- return (-1.0L / (x - x));
+ return (-1.0L / zero); /* log1p(-1) = -inf */
else
return (zero / (x - x));
}