Fix fdim handling of infinities (bug 15797).

diff --git a/ChangeLog b/ChangeLog
index 16e258c8adbb8949267c6b3682850a4d6fa0edab..7b4d6e9214acdd76147193355b606c1e395d2145 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2013-08-21  Joseph Myers  <joseph@codesourcery.com>
+
+       [BZ #15797]
+       * math/s_fdim.c (__fdim): Check for infinite arguments if result
+       is infinite, not alongside NaN test.
+       * math/s_fdimf.c (__fdimf): Likewise.
+       * math/s_fdiml.c (__fdiml): Likewise.
+       * math/libm-test.inc (fdim_test_data): Add more tests.  Test that
+       errno is unchanged.
+
 2013-07-23  Adhemerval Zanella  <azanella@linux.vnet.ibm.com>
 
        [BZ #15867]

diff --git a/NEWS b/NEWS
index ab3f353b83b0e1d639704734b202fd6b38ad4335..0d0a315da5134efd7f874cdd66f011fdff4cca64 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -22,7 +22,7 @@ Version 2.18
   15424, 15426, 15429, 15431, 15432, 15441, 15442, 15448, 15465, 15480,
   15485, 15488, 15490, 15492, 15493, 15497, 15506, 15529, 15536, 15553,
   15577, 15583, 15618, 15627, 15631, 15654, 15655, 15666, 15667, 15674,
-  15711, 15755, 15759.
+  15711, 15755, 15759, 15797.
 
 * CVE-2013-2207 Incorrectly granting access to another user's pseudo-terminal
   has been fixed by disabling the use of pt_chown (Bugzilla #15755).

diff --git a/math/libm-test.inc b/math/libm-test.inc
index 3b382af104960273798a18fe1c4bdc49c64481b9..8c1dcac8e8a92afe00d7e92081849e1b4958b609 100644 (file)
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -8139,33 +8139,37 @@ fabs_test (void)
 
 static const struct test_ff_f_data fdim_test_data[] =
   {
-    TEST_ff_f (fdim, 0, 0, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 9, 0, 9, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 0, 9, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, -9, 0, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 0, -9, 9, NO_INEXACT_EXCEPTION),
-
-    TEST_ff_f (fdim, plus_infty, 9, plus_infty, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, plus_infty, -9, plus_infty, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, minus_infty, 9, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, minus_infty, -9, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 9, minus_infty, plus_infty, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, -9, minus_infty, plus_infty, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 9, plus_infty, 0, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, -9, plus_infty, 0, NO_INEXACT_EXCEPTION),
-
-    TEST_ff_f (fdim, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, 9, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, -9, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, qnan_value, 9, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, qnan_value, -9, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, plus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, minus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, qnan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, qnan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION),
-    TEST_ff_f (fdim, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION),
-
-    TEST_ff_f (fdim, plus_infty, plus_infty, 0, NO_INEXACT_EXCEPTION),
+    TEST_ff_f (fdim, 0, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 9, 0, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 0, 9, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, -9, 0, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 0, -9, 9, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (fdim, plus_infty, 9, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, plus_infty, -9, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, minus_infty, 9, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, minus_infty, -9, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 9, minus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, -9, minus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 9, plus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, -9, plus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (fdim, 0, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, 9, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, -9, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, 0, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, 9, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, -9, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, plus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, minus_infty, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, plus_infty, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, minus_infty, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, qnan_value, qnan_value, qnan_value, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+
+    TEST_ff_f (fdim, plus_infty, plus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, plus_infty, minus_infty, plus_infty, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, minus_infty, plus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_ff_f (fdim, minus_infty, minus_infty, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
   };
 
 static void

diff --git a/math/s_fdim.c b/math/s_fdim.c
index 2f97948b2eaf154aaa656e4355919cd5828bca7a..f8fd80490d5d883489b6c5ee77f265477559f65f 100644 (file)
--- a/math/s_fdim.c
+++ b/math/s_fdim.c
@@ -26,16 +26,16 @@ __fdim (double x, double y)
   int clsx = fpclassify (x);
   int clsy = fpclassify (y);
 
-  if (clsx == FP_NAN || clsy == FP_NAN
-      || (y < 0 && clsx == FP_INFINITE && clsy == FP_INFINITE))
-    /* Raise invalid flag.  */
+  if (clsx == FP_NAN || clsy == FP_NAN)
+    /* Raise invalid flag for signaling but not quiet NaN.  */
     return x - y;
 
   if (x <= y)
     return 0.0;
 
   double r = x - y;
-  if (fpclassify (r) == FP_INFINITE)
+  if (fpclassify (r) == FP_INFINITE
+      && clsx != FP_INFINITE && clsy != FP_INFINITE)
     __set_errno (ERANGE);
 
   return r;

diff --git a/math/s_fdimf.c b/math/s_fdimf.c
index 03810b572842fd99aa41820165d3a55f31274824..86efe6ef2ac9016269a2861b04ee6675c9440e94 100644 (file)
--- a/math/s_fdimf.c
+++ b/math/s_fdimf.c
@@ -26,16 +26,16 @@ __fdimf (float x, float y)
   int clsx = fpclassify (x);
   int clsy = fpclassify (y);
 
-  if (clsx == FP_NAN || clsy == FP_NAN
-      || (y < 0 && clsx == FP_INFINITE && clsy == FP_INFINITE))
-    /* Raise invalid flag.  */
+  if (clsx == FP_NAN || clsy == FP_NAN)
+    /* Raise invalid flag for signaling but not quiet NaN.  */
     return x - y;
 
   if (x <= y)
     return 0.0f;
 
   float r = x - y;
-  if (fpclassify (r) == FP_INFINITE)
+  if (fpclassify (r) == FP_INFINITE
+      && clsx != FP_INFINITE && clsy != FP_INFINITE)
     __set_errno (ERANGE);
 
   return r;

diff --git a/math/s_fdiml.c b/math/s_fdiml.c
index 56045329afecd2553f2487798a1185a1074e1f88..030fcc22e684bebd440028beb987a7d77898974d 100644 (file)
--- a/math/s_fdiml.c
+++ b/math/s_fdiml.c
@@ -26,16 +26,16 @@ __fdiml (long double x, long double y)
   int clsx = fpclassify (x);
   int clsy = fpclassify (y);
 
-  if (clsx == FP_NAN || clsy == FP_NAN
-      || (y < 0 && clsx == FP_INFINITE && clsy == FP_INFINITE))
-    /* Raise invalid flag.  */
+  if (clsx == FP_NAN || clsy == FP_NAN)
+    /* Raise invalid flag for signaling but not quiet NaN.  */
     return x - y;
 
   if (x <= y)
     return 0.0f;
 
   long double r = x - y;
-  if (fpclassify (r) == FP_INFINITE)
+  if (fpclassify (r) == FP_INFINITE
+      && clsx != FP_INFINITE && clsy != FP_INFINITE)
     __set_errno (ERANGE);
 
   return r;