re PR fortran/31202 (Incorrect rounding generated for NINT)

2007-08-05  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>

	PR fortran/31202
	* intrinsics/c99_functions.c (roundl): Provide fallback
	implementation for systems without ceill.
	* c99_protos.h (roundl): Define prototype in all cases.

From-SVN: r127227

libgfortran/ChangeLog

+2007-08-05  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
+
+	PR fortran/31202
+	* intrinsics/c99_functions.c (roundl): Provide fallback
+	implementation for systems without ceill.
+	* c99_protos.h (roundl): Define prototype in all cases.
+
 2007-08-03  Thomas Koenig  <tkoenig@gcc.gnu.org>
 
 	PR libfortran/32977

libgfortran/c99_protos.h

@@ -200,7 +200,7 @@ extern double round(double);
 extern float roundf(float);
 #endif
 
-#if !defined(HAVE_ROUNDL) && defined(HAVE_CEILL)
+#if !defined(HAVE_ROUNDL)
 #define HAVE_ROUNDL 1
 extern long double roundl(long double);
 #endif

libgfortran/intrinsics/c99_functions.c

@@ -500,8 +500,9 @@ powf(float x, float y)
 
 /* Algorithm by Steven G. Kargl.  */
 
-#if !defined(HAVE_ROUNDL) && defined(HAVE_CEILL)
+#if !defined(HAVE_ROUNDL)
 #define HAVE_ROUNDL 1
+#if defined(HAVE_CEILL)
 /* Round to nearest integral value.  If the argument is halfway between two
    integral values then round away from zero.  */
 
@@ -527,6 +528,27 @@ roundl(long double x)
       return (-t);
     }
 }
+#else
+
+/* Poor version of roundl for system that don't have ceill.  */
+long double
+roundl(long double x)
+{
+  if (x > DBL_MAX || x < -DBL_MAX)
+    {
+#ifdef HAVE_NEXTAFTERL
+      static long double prechalf = nexafterl (0.5L, LDBL_MAX);
+#else
+      static long double prechalf = 0.5L;
+#endif
+      return (GFC_INTEGER_LARGEST) (x + (x > 0 ? prechalf : -prechalf));
+    }
+  else
+    /* Use round().  */
+    return round((double) x);
+}
+
+#endif
 #endif
 
 #ifndef HAVE_ROUND