Index: test/my_basics.c
===================================================================
--- test/my_basics.c	(revision 973)
+++ test/my_basics.c	(working copy)
@@ -777,6 +777,31 @@
 }
 
 
+/*
+  Bug #10128 Error in evaluating simple mathematical expression
+  ADO calls SQLNativeSql with a NULL pointer for the result length,
+  but passes a non-NULL result buffer.
+*/
+DECLARE_TEST(t_bug10128)
+{
+  SQLCHAR *query= (SQLCHAR *) "select 1,2,3,4";
+  SQLCHAR nativesql[1000];
+  SQLINTEGER nativelen;
+  SQLINTEGER querylen= (SQLINTEGER) strlen(query);
+
+  ok_con(hdbc, SQLNativeSql(hdbc, query, SQL_NTS, NULL, 0, &nativelen));
+  is_num(nativelen, querylen);
+
+  nativelen= 999;
+
+  ok_con(hdbc, SQLNativeSql(hdbc, query, SQL_NTS, nativesql, 1000, &nativelen));
+  is_num(nativelen, querylen);
+  is_str(nativesql, query, querylen + 1);
+
+  return OK;
+}
+
+
 BEGIN_TESTS
   ADD_TEST(my_basics)
   ADD_TEST(t_max_select)
@@ -798,6 +823,7 @@
   ADD_TEST(setnames_conn)
   ADD_TEST(sqlcancel)
   ADD_TEST(t_bug32014)
+  ADD_TEST(t_bug10128)
 END_TESTS
 
 
Index: driver/ansi.c
===================================================================
--- driver/ansi.c	(revision 973)
+++ driver/ansi.c	(working copy)
@@ -857,7 +857,7 @@
   if (in_len == SQL_NTS)
     in_len= strlen((char *)in);
 
-  if (out)
+  if (out_len)
     *out_len= in_len;
 
   (void)strncpy((char *)out, (const char *)in, out_max);
Index: driver/unicode.c
===================================================================
--- driver/unicode.c	(revision 973)
+++ driver/unicode.c	(working copy)
@@ -717,7 +717,7 @@
   if (in_len == SQL_NTS)
     in_len= sqlwcharlen(in);
 
-  if (out)
+  if (out_len)
     *out_len= in_len;
 
   if (in_len > out_max)
@@ -732,7 +732,7 @@
     out[in_len]= 0;
   }
 
-  return SQL_SUCCESS;
+  return rc;
 }