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

5 files changed, 41 insertions, 20 deletions

diff --git a/sysdeps/ieee754/ldbl-128/strtold_l.c b/sysdeps/ieee754/ldbl-128/strtold_l.c
index 8e0bc03196..d3a1d1e862 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 e5644f5d31..9e94f53b04 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 93415f0f01..04e3288571 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 8182b2bcd0..e9b33f2d80 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 ded84f342b..dccf98c461 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>