[BZ #15522] strtod ("nan(N)") returning a sNaN in some cases

10 files changed, 87 insertions, 32 deletions

diff --git a/ChangeLog b/ChangeLog
index 83b3956..7c1625e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,20 @@
 2013-08-29  Thomas Schwinge  <thomas@codesourcery.com>
 
+	[BZ #15522] strtod ("nan(N)") returning a sNaN in some cases
+
+	* stdlib/strtof_l.c (SET_MANTISSA): Rewrite.
+	* stdlib/strtod_l.c (SET_MANTISSA): Likewise.
+	* sysdeps/ieee754/ldbl-64-128/strtold_l.c (SET_MANTISSA):
+	Likewise.
+	* sysdeps/ieee754/ldbl-96/strtold_l.c (SET_MANTISSA): Likewise.
+	* sysdeps/ieee754/ldbl-128/strtold_l.c (SET_MANTISSA): Likewise.
+	* sysdeps/ieee754/ldbl-128ibm/strtold_l.c (SET_MANTISSA):
+	Likewise.
+	* sysdeps/ieee754/ldbl-128ibm/ieee754.h
+	(ibm_extended_long_double): Add ieee_nan member.
+	* stdlib/tst-strtod6.c (test): New function, renamed from do_test.
+	(do_test): New function.
+
 	* math/basic-test.c (TEST_CONVERT): New macro, renamed from
 	TEST_TRUNC.
 	(convert_dfsf_test, convert_tfsf_test, convert_tfdf_test): New
diff --git a/NEWS b/NEWS
index cb55e7f..d3524ff 100644
--- a/NEWS
+++ b/NEWS
@@ -9,7 +9,8 @@ Version 2.19
 
 * The following bugs are resolved with this release:
 
-  14699, 15531, 15532, 15736, 15749, 15797, 15867, 15890, 15897, 15905.
+  14699, 15522, 15531, 15532, 15736, 15749, 15797, 15867, 15890, 15897,
+  15905.
 
 * CVE-2013-4237 The readdir_r function could write more than NAME_MAX bytes
   to the d_name member of struct dirent, or omit the terminating NUL
diff --git a/stdlib/strtod_l.c b/stdlib/strtod_l.c
index 5b41e2b..8f60653 100644
--- a/stdlib/strtod_l.c
+++ b/stdlib/strtod_l.c
@@ -42,11 +42,10 @@ extern unsigned long long int ____strtoull_l_internal (const char *, char **,
 # define SET_MANTISSA(flt, mant) \
   do { union ieee754_double u;						      \
        u.d = (flt);							      \
-       if ((mant & 0xfffffffffffffULL) == 0)				      \
-	 mant = 0x8000000000000ULL;					      \
-       u.ieee.mantissa0 = ((mant) >> 32) & 0xfffff;			      \
-       u.ieee.mantissa1 = (mant) & 0xffffffff;				      \
-       (flt) = u.d;							      \
+       u.ieee_nan.mantissa0 = (mant) >> 32;				      \
+       u.ieee_nan.mantissa1 = (mant);					      \
+       if ((u.ieee.mantissa0 | u.ieee.mantissa1) != 0)			      \
+	 (flt) = u.d;							      \
   } while (0)
 #endif
 /* End of configuration part.  */
diff --git a/stdlib/strtof_l.c b/stdlib/strtof_l.c
index 6fb44bd..c4c1c1f 100644
--- a/stdlib/strtof_l.c
+++ b/stdlib/strtof_l.c
@@ -37,10 +37,9 @@ extern unsigned long long int ____strtoull_l_internal (const char *, char **,
 #define SET_MANTISSA(flt, mant) \
   do { union ieee754_float u;						      \
        u.f = (flt);							      \
-       if ((mant & 0x7fffff) == 0)					      \
-	 mant = 0x400000;						      \
-       u.ieee.mantissa = (mant) & 0x7fffff;				      \
-       (flt) = u.f;							      \
+       u.ieee_nan.mantissa = (mant);					      \
+       if (u.ieee.mantissa != 0)					      \
+	 (flt) = u.f;							      \
   } while (0)
 
 #include "strtod_l.c"
diff --git a/stdlib/tst-strtod6.c b/stdlib/tst-strtod6.c
index 1d87266..15e79fd 100644
--- a/stdlib/tst-strtod6.c
+++ b/stdlib/tst-strtod6.c
@@ -4,12 +4,13 @@
 #include <string.h>
 
 static int
-do_test (void)
+test (const char str[])
 {
-  static const char str[] = "NaN(blabla)something";
   char *endp;
   int result = 0;
 
+  puts (str);
+
   double d = strtod (str, &endp);
   if (!isnan (d))
     {
@@ -64,5 +65,24 @@ do_test (void)
   return result;
 }
 
+static int
+do_test (void)
+{
+  int result = 0;
+
+  result |= test ("NaN(blabla)something");
+  result |= test ("NaN(1234)something");
+  /* UINT32_MAX.  */
+  result |= test ("NaN(4294967295)something");
+  /* UINT64_MAX.  */
+  result |= test ("NaN(18446744073709551615)something");
+  /* The case of zero is special in that "something" has to be done to make the
+     mantissa different from zero, which would mean infinity instead of
+     NaN.  */
+  result |= test ("NaN(0)something");
+
+  return result;
+}
+
 #define TEST_FUNCTION do_test ()
 #include "../test-skeleton.c"
diff --git a/sysdeps/ieee754/ldbl-128/strtold_l.c b/sysdeps/ieee754/ldbl-128/strtold_l.c
index 8e0bc03..d3a1d1e 100644
--- a/sysdeps/ieee754/ldbl-128/strtold_l.c
+++ b/sysdeps/ieee754/ldbl-128/strtold_l.c
@@ -34,11 +34,13 @@
 #define SET_MANTISSA(flt, mant) \
   do { union ieee854_long_double u;					      \
        u.d = (flt);							      \
-       u.ieee.mantissa0 = 0x8000;					      \
-       u.ieee.mantissa1 = 0;						      \
-       u.ieee.mantissa2 = ((mant) >> 32);	      			      \
-       u.ieee.mantissa3 = (mant) & 0xffffffff;				      \
-       (flt) = u.d;							      \
+       u.ieee_nan.mantissa0 = 0;					      \
+       u.ieee_nan.mantissa1 = 0;					      \
+       u.ieee_nan.mantissa2 = (mant) >> 32;				      \
+       u.ieee_nan.mantissa3 = (mant);					      \
+       if ((u.ieee.mantissa0 | u.ieee.mantissa1				      \
+	    | u.ieee.mantissa2 | u.ieee.mantissa3) != 0)		      \
+	 (flt) = u.d;							      \
   } while (0)
 
 #include <strtod_l.c>
diff --git a/sysdeps/ieee754/ldbl-128ibm/ieee754.h b/sysdeps/ieee754/ldbl-128ibm/ieee754.h
index e5644f5..9e94f53 100644
--- a/sysdeps/ieee754/ldbl-128ibm/ieee754.h
+++ b/sysdeps/ieee754/ldbl-128ibm/ieee754.h
@@ -199,6 +199,25 @@ union ibm_extended_long_double
 	unsigned int mantissa2:20;
 	unsigned int mantissa3:32;
       } ieee;
+
+    /* This format makes it easier to see if a NaN is a signalling NaN.  */
+    struct
+      { /* Big endian.  There is no other.  */
+
+	unsigned int negative:1;
+	unsigned int exponent:11;
+	unsigned int quiet_nan:1;
+	/* Together Mantissa0-3 comprise the mantissa.  */
+	unsigned int mantissa0:19;
+	unsigned int mantissa1:32;
+
+	unsigned int negative2:1;
+	unsigned int exponent2:11;
+	/* There is an implied 1 here?  */
+	/* Together these comprise the mantissa.  */
+	unsigned int mantissa2:20;
+	unsigned int mantissa3:32;
+      } ieee_nan;
    };
 
 #define IBM_EXTENDED_LONG_DOUBLE_BIAS 0x3ff /* Added to exponent.  */
diff --git a/sysdeps/ieee754/ldbl-128ibm/strtold_l.c b/sysdeps/ieee754/ldbl-128ibm/strtold_l.c
index 93415f0..04e3288 100644
--- a/sysdeps/ieee754/ldbl-128ibm/strtold_l.c
+++ b/sysdeps/ieee754/ldbl-128ibm/strtold_l.c
@@ -44,11 +44,10 @@ libc_hidden_proto (STRTOF)
 # define SET_MANTISSA(flt, mant) \
   do { union ibm_extended_long_double u;				      \
        u.d = (flt);							      \
-       if ((mant & 0xfffffffffffffULL) == 0)				      \
-	 mant = 0x8000000000000ULL;					      \
-       u.ieee.mantissa0 = ((mant) >> 32) & 0xfffff;			      \
-       u.ieee.mantissa1 = (mant) & 0xffffffff;				      \
-       (flt) = u.d;							      \
+       u.ieee_nan.mantissa0 = (mant) >> 32;				      \
+       u.ieee_nan.mantissa1 = (mant);					      \
+       if ((u.ieee.mantissa0 | u.ieee.mantissa1) != 0)			      \
+	 (flt) = u.d;							      \
   } while (0)
 
 #include <strtod_l.c>
diff --git a/sysdeps/ieee754/ldbl-64-128/strtold_l.c b/sysdeps/ieee754/ldbl-64-128/strtold_l.c
index 8182b2b..e9b33f2 100644
--- a/sysdeps/ieee754/ldbl-64-128/strtold_l.c
+++ b/sysdeps/ieee754/ldbl-64-128/strtold_l.c
@@ -44,11 +44,13 @@ libc_hidden_proto (STRTOF)
 #define SET_MANTISSA(flt, mant) \
   do { union ieee854_long_double u;					      \
        u.d = (flt);							      \
-       u.ieee.mantissa0 = 0x8000;					      \
-       u.ieee.mantissa1 = 0;						      \
-       u.ieee.mantissa2 = ((mant) >> 32);	      			      \
-       u.ieee.mantissa3 = (mant) & 0xffffffff;				      \
-       (flt) = u.d;							      \
+       u.ieee_nan.mantissa0 = 0;					      \
+       u.ieee_nan.mantissa1 = 0;					      \
+       u.ieee_nan.mantissa2 = (mant) >> 32;				      \
+       u.ieee_nan.mantissa3 = (mant);					      \
+       if ((u.ieee.mantissa0 | u.ieee.mantissa1				      \
+	    | u.ieee.mantissa2 | u.ieee.mantissa3) != 0)		      \
+	 (flt) = u.d;							      \
   } while (0)
 
 #include <strtod_l.c>
diff --git a/sysdeps/ieee754/ldbl-96/strtold_l.c b/sysdeps/ieee754/ldbl-96/strtold_l.c
index ded84f3..dccf98c 100644
--- a/sysdeps/ieee754/ldbl-96/strtold_l.c
+++ b/sysdeps/ieee754/ldbl-96/strtold_l.c
@@ -34,11 +34,10 @@
 #define SET_MANTISSA(flt, mant) \
   do { union ieee854_long_double u;					      \
        u.d = (flt);							      \
-       if ((mant & 0x7fffffffffffffffULL) == 0)				      \
-	 mant = 0x4000000000000000ULL;					      \
-       u.ieee.mantissa0 = (((mant) >> 32) & 0x7fffffff) | 0x80000000;	      \
-       u.ieee.mantissa1 = (mant) & 0xffffffff;				      \
-       (flt) = u.d;							      \
+       u.ieee_nan.mantissa0 = (mant) >> 32;				      \
+       u.ieee_nan.mantissa1 = (mant);					      \
+       if ((u.ieee.mantissa0 | u.ieee.mantissa1) != 0)			      \
+	 (flt) = u.d;							      \
   } while (0)
 
 #include <stdlib/strtod_l.c>