diff --git a/lldb/scripts/Python/interface/SBCommandReturnObject.i b/lldb/scripts/Python/interface/SBCommandReturnObject.i
index e72c1e2731f4..7cec06943bf8 100644
--- a/lldb/scripts/Python/interface/SBCommandReturnObject.i
+++ b/lldb/scripts/Python/interface/SBCommandReturnObject.i
@@ -84,7 +84,7 @@ public:
     SetImmediateErrorFile (FILE *fh);
 
 	void
-	PutCString(const char* string, int len = -1);
+	PutCString(const char* string, int len);
 
     // wrapping the variadic Printf() with a plain Print()
     // because it is hard to support varargs in SWIG bridgings
diff --git a/lldb/scripts/Python/python-typemaps.swig b/lldb/scripts/Python/python-typemaps.swig
index 1a67f7b4971b..8af1446aef3d 100644
--- a/lldb/scripts/Python/python-typemaps.swig
+++ b/lldb/scripts/Python/python-typemaps.swig
@@ -442,3 +442,26 @@
 #endif
    $result = PyFile_FromFile($1, const_cast<char*>(""), mode, fclose);
 }
+
+%typemap(in) (const char* string, int len) {
+    if ($input == Py_None)
+    {
+        $1 = NULL;
+        $2 = 0;
+    }
+    else if (PyUnicode_Check($input))
+    {
+        $1 = PyString_AsString(PyUnicode_AsUTF8String($input));
+        $2 = strlen($1);
+    }
+    else if (PyString_Check($input))
+    {
+        $1 = PyString_AsString($input);
+        $2 = PyString_Size($input);
+    }
+    else
+    {
+        PyErr_SetString(PyExc_TypeError,"not a string-like object");
+        return NULL;
+    }
+}
diff --git a/lldb/source/API/SBCommandReturnObject.cpp b/lldb/source/API/SBCommandReturnObject.cpp
index ee7008af3c7a..b0533e132db3 100644
--- a/lldb/source/API/SBCommandReturnObject.cpp
+++ b/lldb/source/API/SBCommandReturnObject.cpp
@@ -281,7 +281,7 @@ SBCommandReturnObject::PutCString(const char* string, int len)
 {
     if (m_opaque_ap.get())
     {
-        if (len == 0)
+        if (len == 0 || string == NULL || *string == 0)
         {
             return;
         }