[BZ #16824] Fix failing y1 due to too large ulps in downward/upward rounding mode.

diff --git a/ChangeLog b/ChangeLog
index 4a714106594834767d3d60fde53e923fc810fc13..a4eba04b7cfa93a8ec9fa0135e47ac94c3cf8c69 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2014-04-16  Stefan Liebler  <stli@linux.vnet.ibm.com>
+
+       [BZ #16824]
+       * sysdeps/ieee754/ldbl-128/e_j1l.c (__ieee754_y1l):
+       Set round-to-nearest internally to reduce error accumulation.
+
 2014-04-16  Alan Modra  <amodra@gmail.com>
 
        [BZ #16740]

diff --git a/NEWS b/NEWS
index 867a3d6199f34fb09b96d5d64ae7e7d9bddd136e..6a6580997efd36ad8eb25ae8c05c5d4d6492d5db 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -14,7 +14,7 @@ Version 2.20
   16610, 16611, 16613, 16619, 16623, 16632, 16634, 16639, 16642, 16648,
   16649, 16670, 16674, 16677, 16680, 16683, 16689, 16695, 16701, 16706,
   16707, 16712, 16713, 16714, 16731, 16739, 16740, 16743, 16758, 16759,
-  16760, 16770, 16786, 16789, 16799, 16800, 16815, 16831, 16838.
+  16760, 16770, 16786, 16789, 16799, 16800, 16815, 16824, 16831, 16838.
 
 * Running the testsuite no longer terminates as soon as a test fails.
   Instead, a file tests.sum (xtests.sum from "make xcheck") is generated,

diff --git a/sysdeps/ieee754/ldbl-128/e_j1l.c b/sysdeps/ieee754/ldbl-128/e_j1l.c
index 70a1c86fd2d55f2fa89447bf6a6eb027452ed455..1264c95d49802abaf9a9bd952d0997e48beca6e3 100644 (file)
--- a/sysdeps/ieee754/ldbl-128/e_j1l.c
+++ b/sysdeps/ieee754/ldbl-128/e_j1l.c
@@ -856,6 +856,7 @@ __ieee754_y1l (long double x)
   if (xx <= 2.0L)
     {
       /* 0 <= x <= 2 */
+      SET_RESTORE_ROUNDL (FE_TONEAREST);
       z = xx * xx;
       p = xx * neval (z, Y0_2N, NY0_2N) / deval (z, Y0_2D, NY0_2D);
       p = -TWOOPI / xx + p;