Fix catan, catanh missing underflows (bug 15406).

9 files changed, 152 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 1996e6c04a..225236c6d8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,27 @@
 2013-04-26  Joseph Myers  <joseph@codesourcery.com>
 
+	[BZ #15406]
+	* math/s_catan.c: Include <float.h>.
+	(__catan): Ensure underflow exception occurs for underflowed
+	result.
+	* math/s_catanf.c: Include <float.h>.
+	(__catanf): Ensure underflow exception occurs for underflowed
+	result.
+	* math/s_catanh.c: Include <float.h>.
+	(__catanh): Ensure underflow exception occurs for underflowed
+	result.
+	* math/s_catanhf.c: Include <float.h>.
+	(__catanhf): Ensure underflow exception occurs for underflowed
+	result.
+	* math/s_catanhl.c: Include <float.h>.
+	(__catanhl): Ensure underflow exception occurs for underflowed
+	result.
+	* math/s_catanl.c: Include <float.h>.
+	(__catanl): Ensure underflow exception occurs for underflowed
+	result.
+	* math/libm-test.inc (catan_test): Add more tests.
+	(catanh_test): Likewise.
+
 	[BZ #15405]
 	* math/s_ccosh.c (__ccosh): Ensure underflow exception occurs for
 	underflowed result.
diff --git a/NEWS b/NEWS
index f986862b97..e8e7468055 100644
--- a/NEWS
+++ b/NEWS
@@ -14,7 +14,8 @@ Version 2.18
   14812, 14888, 14920, 14964, 14981, 14982, 14985, 14994, 14996, 15003,
   15006, 15020, 15023, 15036, 15054, 15055, 15062, 15078, 15160, 15214,
   15232, 15234, 15283, 15285, 15287, 15304, 15305, 15307, 15309, 15327,
-  15330, 15335, 15336, 15337, 15342, 15346, 15361, 15366, 15394, 15405.
+  15330, 15335, 15336, 15337, 15342, 15346, 15361, 15366, 15394, 15405,
+  15406.
 
 * CVE-2013-0242 Buffer overrun in regexp matcher has been fixed (Bugzilla
   #15078).
diff --git a/math/libm-test.inc b/math/libm-test.inc
index a3d7731531..a62ae9a11f 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -4336,6 +4336,34 @@ catan_test (void)
   TEST_c_c (catan, 0.0L, -0x1p5000L, 1.570796326794896619231321691639751442099L, -7.079811261048172892385615158694057552948e-1506L);
   TEST_c_c (catan, -0.0L, -0x1p5000L, -1.570796326794896619231321691639751442099L, -7.079811261048172892385615158694057552948e-1506L);
 #endif
+  TEST_c_c (catan, 0x1p63L, 0.5L, 1.570796326794896619122901474391200998698L, 5.877471754111437539843682686111228389007e-39L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catan, 0x1p63L, -0.5L, 1.570796326794896619122901474391200998698L, -5.877471754111437539843682686111228389007e-39L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catan, -0x1p63L, 0.5L, -1.570796326794896619122901474391200998698L, 5.877471754111437539843682686111228389007e-39L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catan, -0x1p63L, -0.5L, -1.570796326794896619122901474391200998698L, -5.877471754111437539843682686111228389007e-39L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catan, 0.5L, 0x1p63L, 1.570796326794896619231321691639751442093L, 1.084202172485504434007452800869941711427e-19L);
+  TEST_c_c (catan, -0.5L, 0x1p63L, -1.570796326794896619231321691639751442093L, 1.084202172485504434007452800869941711427e-19L);
+  TEST_c_c (catan, 0.5L, -0x1p63L, 1.570796326794896619231321691639751442093L, -1.084202172485504434007452800869941711427e-19L);
+  TEST_c_c (catan, -0.5L, -0x1p63L, -1.570796326794896619231321691639751442093L, -1.084202172485504434007452800869941711427e-19L);
+#ifndef TEST_FLOAT
+  TEST_c_c (catan, 0x1p511L, 0.5L, 1.570796326794896619231321691639751442099L, 1.112536929253600691545116358666202032110e-308L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catan, 0x1p511L, -0.5L, 1.570796326794896619231321691639751442099L, -1.112536929253600691545116358666202032110e-308L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catan, -0x1p511L, 0.5L, -1.570796326794896619231321691639751442099L, 1.112536929253600691545116358666202032110e-308L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catan, -0x1p511L, -0.5L, -1.570796326794896619231321691639751442099L, -1.112536929253600691545116358666202032110e-308L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catan, 0.5L, 0x1p511L, 1.570796326794896619231321691639751442099L, 1.491668146240041348658193063092586767475e-154L);
+  TEST_c_c (catan, -0.5L, 0x1p511L, -1.570796326794896619231321691639751442099L, 1.491668146240041348658193063092586767475e-154L);
+  TEST_c_c (catan, 0.5L, -0x1p511L, 1.570796326794896619231321691639751442099L, -1.491668146240041348658193063092586767475e-154L);
+  TEST_c_c (catan, -0.5L, -0x1p511L, -1.570796326794896619231321691639751442099L, -1.491668146240041348658193063092586767475e-154L);
+#endif
+#if defined TEST_LDOUBLE && LDBL_MAX_EXP >= 16384
+  TEST_c_c (catan, 0x1p8191L, 0.5L, 1.570796326794896619231321691639751442099L, 1.681051571556046753131338908660876301299e-4932L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catan, 0x1p8191L, -0.5L, 1.570796326794896619231321691639751442099L, -1.681051571556046753131338908660876301299e-4932L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catan, -0x1p8191L, 0.5L, -1.570796326794896619231321691639751442099L, 1.681051571556046753131338908660876301299e-4932L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catan, -0x1p8191L, -0.5L, -1.570796326794896619231321691639751442099L, -1.681051571556046753131338908660876301299e-4932L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catan, 0.5L, 0x1p8191L, 1.570796326794896619231321691639751442099L, 1.833603867554847165621412392048483165956e-2466L);
+  TEST_c_c (catan, -0.5L, 0x1p8191L, -1.570796326794896619231321691639751442099L, 1.833603867554847165621412392048483165956e-2466L);
+  TEST_c_c (catan, 0.5L, -0x1p8191L, 1.570796326794896619231321691639751442099L, -1.833603867554847165621412392048483165956e-2466L);
+  TEST_c_c (catan, -0.5L, -0x1p8191L, -1.570796326794896619231321691639751442099L, -1.833603867554847165621412392048483165956e-2466L);
+#endif
 
   TEST_c_c (catan, 0.75L, 1.25L, 1.10714871779409050301706546017853704L, 0.549306144334054845697622618461262852L);
   TEST_c_c (catan, -2, -3, -1.4099210495965755225306193844604208L, -0.22907268296853876629588180294200276L);
@@ -4440,6 +4468,34 @@ catanh_test (void)
   TEST_c_c (catanh, 0.0L, -0x1p5000L, 0.0L, -1.570796326794896619231321691639751442099L);
   TEST_c_c (catanh, -0.0L, -0x1p5000L, -0.0L, -1.570796326794896619231321691639751442099L);
 #endif
+  TEST_c_c (catanh, 0x1p63L, 0.5L, 1.084202172485504434007452800869941711427e-19L, 1.570796326794896619231321691639751442093L);
+  TEST_c_c (catanh, 0x1p63L, -0.5L, 1.084202172485504434007452800869941711427e-19L, -1.570796326794896619231321691639751442093L);
+  TEST_c_c (catanh, -0x1p63L, 0.5L, -1.084202172485504434007452800869941711427e-19L, 1.570796326794896619231321691639751442093L);
+  TEST_c_c (catanh, -0x1p63L, -0.5L, -1.084202172485504434007452800869941711427e-19L, -1.570796326794896619231321691639751442093L);
+  TEST_c_c (catanh, 0.5L, 0x1p63L, 5.877471754111437539843682686111228389007e-39L, 1.570796326794896619122901474391200998698L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catanh, -0.5L, 0x1p63L, -5.877471754111437539843682686111228389007e-39L, 1.570796326794896619122901474391200998698L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catanh, 0.5L, -0x1p63L, 5.877471754111437539843682686111228389007e-39L, -1.570796326794896619122901474391200998698L, UNDERFLOW_EXCEPTION_FLOAT);
+  TEST_c_c (catanh, -0.5L, -0x1p63L, -5.877471754111437539843682686111228389007e-39L, -1.570796326794896619122901474391200998698L, UNDERFLOW_EXCEPTION_FLOAT);
+#ifndef TEST_FLOAT
+  TEST_c_c (catanh, 0x1p511L, 0.5L, 1.491668146240041348658193063092586767475e-154L, 1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, 0x1p511L, -0.5L, 1.491668146240041348658193063092586767475e-154L, -1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, -0x1p511L, 0.5L, -1.491668146240041348658193063092586767475e-154L, 1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, -0x1p511L, -0.5L, -1.491668146240041348658193063092586767475e-154L, -1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, 0.5L, 0x1p511L, 1.112536929253600691545116358666202032110e-308L, 1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catanh, -0.5L, 0x1p511L, -1.112536929253600691545116358666202032110e-308L, 1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catanh, 0.5L, -0x1p511L, 1.112536929253600691545116358666202032110e-308L, -1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION_DOUBLE);
+  TEST_c_c (catanh, -0.5L, -0x1p511L, -1.112536929253600691545116358666202032110e-308L, -1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION_DOUBLE);
+#endif
+#if defined TEST_LDOUBLE && LDBL_MAX_EXP >= 16384
+  TEST_c_c (catanh, 0x1p8191L, 0.5L, 1.833603867554847165621412392048483165956e-2466L, 1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, 0x1p8191L, -0.5L, 1.833603867554847165621412392048483165956e-2466L, -1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, -0x1p8191L, 0.5L, -1.833603867554847165621412392048483165956e-2466L, 1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, -0x1p8191L, -0.5L, -1.833603867554847165621412392048483165956e-2466L, -1.570796326794896619231321691639751442099L);
+  TEST_c_c (catanh, 0.5L, 0x1p8191L, 1.681051571556046753131338908660876301299e-4932L, 1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catanh, -0.5L, 0x1p8191L, -1.681051571556046753131338908660876301299e-4932L, 1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catanh, 0.5L, -0x1p8191L, 1.681051571556046753131338908660876301299e-4932L, -1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION);
+  TEST_c_c (catanh, -0.5L, -0x1p8191L, -1.681051571556046753131338908660876301299e-4932L, -1.570796326794896619231321691639751442099L, UNDERFLOW_EXCEPTION);
+#endif
 
   TEST_c_c (catanh, 0.75L, 1.25L, 0.261492138795671927078652057366532140L, 0.996825126463918666098902241310446708L);
   TEST_c_c (catanh, -2, -3, -0.14694666622552975204743278515471595L, -1.3389725222944935611241935759091443L);
diff --git a/math/s_catan.c b/math/s_catan.c
index 783941a72e..6a1016e74c 100644
--- a/math/s_catan.c
+++ b/math/s_catan.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ double
 __catan (__complex__ double x)
@@ -83,6 +83,17 @@ __catan (__complex__ double x)
 	  num = 4.0 * __imag__ x;
 	  __imag__ res = 0.25 * __log1p (num / den);
 	}
+
+      if (fabs (__real__ res) < DBL_MIN)
+	{
+	  volatile double force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabs (__imag__ res) < DBL_MIN)
+	{
+	  volatile double force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;
diff --git a/math/s_catanf.c b/math/s_catanf.c
index 3ffc6db52c..d0d188ca0b 100644
--- a/math/s_catanf.c
+++ b/math/s_catanf.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ float
 __catanf (__complex__ float x)
@@ -83,6 +83,17 @@ __catanf (__complex__ float x)
 	  num = 4.0f * __imag__ x;
 	  __imag__ res = 0.25f * __log1pf (num / den);
 	}
+
+      if (fabsf (__real__ res) < FLT_MIN)
+	{
+	  volatile float force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabsf (__imag__ res) < FLT_MIN)
+	{
+	  volatile float force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;
diff --git a/math/s_catanh.c b/math/s_catanh.c
index 0ee8c64b6f..5d18cd639f 100644
--- a/math/s_catanh.c
+++ b/math/s_catanh.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ double
 __catanh (__complex__ double x)
@@ -76,6 +76,17 @@ __catanh (__complex__ double x)
       den = 1 - __real__ x * __real__ x - i2;
 
       __imag__ res = 0.5 * __ieee754_atan2 (2.0 * __imag__ x, den);
+
+      if (fabs (__real__ res) < DBL_MIN)
+	{
+	  volatile double force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabs (__imag__ res) < DBL_MIN)
+	{
+	  volatile double force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;
diff --git a/math/s_catanhf.c b/math/s_catanhf.c
index 9d90a00c83..6376a2ccb7 100644
--- a/math/s_catanhf.c
+++ b/math/s_catanhf.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ float
 __catanhf (__complex__ float x)
@@ -76,6 +76,17 @@ __catanhf (__complex__ float x)
       den = 1 - __real__ x * __real__ x - i2;
 
       __imag__ res = 0.5f * __ieee754_atan2f (2.0f * __imag__ x, den);
+
+      if (fabsf (__real__ res) < FLT_MIN)
+	{
+	  volatile float force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabsf (__imag__ res) < FLT_MIN)
+	{
+	  volatile float force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;
diff --git a/math/s_catanhl.c b/math/s_catanhl.c
index 7e2b894257..30fd27703b 100644
--- a/math/s_catanhl.c
+++ b/math/s_catanhl.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ long double
 __catanhl (__complex__ long double x)
@@ -76,6 +76,17 @@ __catanhl (__complex__ long double x)
       den = 1 - __real__ x * __real__ x - i2;
 
       __imag__ res = 0.5L * __ieee754_atan2l (2.0L * __imag__ x, den);
+
+      if (fabsl (__real__ res) < LDBL_MIN)
+	{
+	  volatile long double force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabsl (__imag__ res) < LDBL_MIN)
+	{
+	  volatile long double force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;
diff --git a/math/s_catanl.c b/math/s_catanl.c
index 67b6b52d1d..2440e6d151 100644
--- a/math/s_catanl.c
+++ b/math/s_catanl.c
@@ -20,7 +20,7 @@
 #include <complex.h>
 #include <math.h>
 #include <math_private.h>
-
+#include <float.h>
 
 __complex__ long double
 __catanl (__complex__ long double x)
@@ -83,6 +83,17 @@ __catanl (__complex__ long double x)
 	  num = 4.0L * __imag__ x;
 	  __imag__ res = 0.25L * __log1pl (num / den);
 	}
+
+      if (fabsl (__real__ res) < LDBL_MIN)
+	{
+	  volatile long double force_underflow = __real__ res * __real__ res;
+	  (void) force_underflow;
+	}
+      if (fabsl (__imag__ res) < LDBL_MIN)
+	{
+	  volatile long double force_underflow = __imag__ res * __imag__ res;
+	  (void) force_underflow;
+	}
     }
 
   return res;