Improve dpow() check for ERANGE overflow for HPPA.

src/backend/utils/adt/float.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.143 2007/01/06 02:28:38 tgl Exp $
+ *	  $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.144 2007/01/06 04:14:55 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1459,10 +1459,9 @@ dpow(PG_FUNCTION_ARGS)
 		else
 			result = 1;
 	}
-	else if (errno == ERANGE)
-	{
-		result = (arg1 >= 0) ? get_float8_infinity() : -get_float8_infinity();
-	}
+	/* Some platoforms, e.g. HPPA, return ERANGE, but HUGE_VAL, not Inf */
+	else if (errno == ERANGE && !isinf(result))
+		result = get_float8_infinity();
 	
 	CHECKFLOATVAL(result, isinf(arg1) || isinf(arg2), arg1 == 0);
 	PG_RETURN_FLOAT8(result);