From 2ca180e97a16f3ee3ec9e7e5a5fb7eda3d863a02 Mon Sep 17 00:00:00 2001 From: Stefan Liebler Date: Tue, 29 Apr 2014 15:43:36 +0200 Subject: [PATCH] [BZ #16823] Fix log1pl returning wrong infinity sign --- ChangeLog | 8 ++++++++ sysdeps/ieee754/dbl-64/s_log1p.c | 2 +- sysdeps/ieee754/flt-32/s_log1pf.c | 2 +- sysdeps/ieee754/ldbl-128/s_log1pl.c | 2 +- 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 + + [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 * 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)); } -- 2.7.4