diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_fma.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128/s_fma.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_fma.c b/sysdeps/ieee754/ldbl-128/s_fma.c index 355b60ebbb..b08ff29c04 100644 --- a/sysdeps/ieee754/ldbl-128/s_fma.c +++ b/sysdeps/ieee754/ldbl-128/s_fma.c @@ -1,5 +1,5 @@ /* Compute x * y + z as ternary operation. - Copyright (C) 2010 Free Software Foundation, Inc. + Copyright (C) 2010-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Jakub Jelinek <jakub@redhat.com>, 2010. @@ -33,6 +33,12 @@ __fma (double x, double y, double z) fenv_t env; /* Multiplication is always exact. */ long double temp = (long double) x * (long double) y; + + /* Ensure correct sign of an exact zero result by performing the + addition in the original rounding mode in that case. */ + if (temp == -z) + return (double) temp + z; + union ieee854_long_double u; feholdexcept (&env); fesetround (FE_TOWARDZERO); |