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Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_fmaf.c')
-rw-r--r--sysdeps/ieee754/dbl-64/s_fmaf.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_fmaf.c b/sysdeps/ieee754/dbl-64/s_fmaf.c
index e7a0650f0f..a4f12d9f76 100644
--- a/sysdeps/ieee754/dbl-64/s_fmaf.c
+++ b/sysdeps/ieee754/dbl-64/s_fmaf.c
@@ -32,8 +32,15 @@ float
__fmaf (float x, float y, float z)
{
fenv_t env;
+
/* Multiplication is always exact. */
double temp = (double) x * (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 (float) temp + z;
+
union ieee754_double u;
libc_feholdexcept_setround (&env, FE_TOWARDZERO);