1 files changed, 9 insertions, 0 deletions
diff --git a/sql/sql_string.h b/sql/sql_string.h
index 79365b7481b..ad32305e9b4 100644
--- a/sql/sql_string.h
+++ b/sql/sql_string.h
@@ -95,9 +95,18 @@ public:
       Ptr[str_length]=0;
     return Ptr;
   }
+  inline char *c_ptr_safe()
+  {
+    if (Ptr && str_length < Alloced_length)
+      Ptr[str_length]=0;
+    else
+      (void) realloc(str_length);
+    return Ptr;
+  }
 
   void set(String &str,uint32 offset,uint32 arg_length)
   {
+    DBUG_ASSERT(&str != this);
     free();
     Ptr=(char*) str.ptr()+offset; str_length=arg_length; alloced=0;
     if (str.Alloced_length)