about summary refs log tree commit diff
diff options
context:
space:
mode:
authorJoseph Myers <joseph@codesourcery.com>2012-11-22 14:57:22 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-11-22 14:57:22 +0000
commit8e27e3cc453849158e069dbed0eea7b8113ab8ff (patch)
tree4f4b8ecd14b90dc0f283fdc002d2cbef94cba7e2
parentc9c0279bcb2bd0871e9a4affbab3244389de1353 (diff)
downloadglibc-8e27e3cc453849158e069dbed0eea7b8113ab8ff.tar.gz
glibc-8e27e3cc453849158e069dbed0eea7b8113ab8ff.tar.xz
glibc-8e27e3cc453849158e069dbed0eea7b8113ab8ff.zip
Fix ldbl-128ibm hypotl inaccuracy for arguments with large ratio (bug 14868).
-rw-r--r--ChangeLog5
-rw-r--r--NEWS2
-rw-r--r--math/libm-test.inc2
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/e_hypotl.c2
4 files changed, 9 insertions, 2 deletions
diff --git a/ChangeLog b/ChangeLog
index c2421fa10d..69dd8fe2d8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2012-11-22  Joseph Myers  <joseph@codesourcery.com>
 
+	[BZ #14868]
+	* sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl):
+	Return a+b for ratio over 2**120, not 2**60.
+	* math/libm-test.inc (hypot_test): Add another test.
+
 	* math/libm-test.inc (clog_test): Use
 	UNDERFLOW_EXCEPTION_LDOUBLE_IBM on two tests.
 	(clog10_test): Likewise.
diff --git a/NEWS b/NEWS
index c17a5573f0..94e1260137 100644
--- a/NEWS
+++ b/NEWS
@@ -21,7 +21,7 @@ Version 2.17
   14638, 14645, 14648, 14652, 14660, 14661, 14669, 14672, 14683, 14694,
   14716, 14719, 14743, 14767, 14783, 14784, 14785, 14793, 14796, 14797,
   14801, 14805, 14807, 14809, 14811, 14815, 14821, 14822, 14824, 14828,
-  14831, 14835, 14838, 14856, 14863, 14865, 14866.
+  14831, 14835, 14838, 14856, 14863, 14865, 14866, 14868.
 
 * Port to ARM AArch64 contributed by Linaro.
 
diff --git a/math/libm-test.inc b/math/libm-test.inc
index 74ef15b212..21f46469de 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -5730,6 +5730,8 @@ hypot_test (void)
 
   TEST_ff_f (hypot, 0.75L, 1.25L, 1.45773797371132511771853821938639577L);
 
+  TEST_ff_f (hypot, 1.0L, 0x1p-61L, 1.0L);
+
 #if !(defined TEST_FLOAT && defined TEST_INLINE)
   TEST_ff_f (hypot, 0x3p125L, 0x4p125L, 0x5p125L);
   TEST_ff_f (hypot, 0x1.234566p-126L, 0x1.234566p-126L, 1.891441686191081936598531534017449451173e-38L);
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c b/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
index 00bfb15926..ce21194cd5 100644
--- a/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/e_hypotl.c
@@ -61,7 +61,7 @@ __ieee754_hypotl(long double x, long double y)
 	if(hb > ha) {a=y;b=x;j=ha; ha=hb;hb=j;} else {a=x;b=y;}
 	a = fabsl(a);	/* a <- |a| */
 	b = fabsl(b);	/* b <- |b| */
-	if((ha-hb)>0x3c0000000000000LL) {return a+b;} /* x/y > 2**60 */
+	if((ha-hb)>0x780000000000000LL) {return a+b;} /* x/y > 2**120 */
 	k=0;
 	kld = 1.0L;
 	if(ha > 0x5f30000000000000LL) {	/* a>2**500 */