Index: lldb/include/lldb/Target/Process.h
===================================================================
--- lldb/include/lldb/Target/Process.h
+++ lldb/include/lldb/Target/Process.h
@@ -2932,7 +2932,6 @@
   bool m_stdin_forward; /// Remember if stdin must be forwarded to remote debug
                         /// server
   std::string m_stdout_data;
-  std::string m_stderr_data;
   std::recursive_mutex m_profile_data_comm_mutex;
   std::vector<std::string> m_profile_data;
   Predicate<uint32_t> m_iohandler_sync;
@@ -3044,8 +3043,6 @@
 
   void AppendSTDOUT(const char *s, size_t len);
 
-  void AppendSTDERR(const char *s, size_t len);
-
   void BroadcastAsyncProfileData(const std::string &one_profile_data);
 
   static void STDIOReadThreadBytesReceived(void *baton, const void *src,
Index: lldb/source/Target/Process.cpp
===================================================================
--- lldb/source/Target/Process.cpp
+++ lldb/source/Target/Process.cpp
@@ -429,7 +429,7 @@
       m_breakpoint_site_list(), m_dynamic_checkers_up(),
       m_unix_signals_sp(unix_signals_sp), m_abi_sp(), m_process_input_reader(),
       m_stdio_communication("process.stdio"), m_stdio_communication_mutex(),
-      m_stdin_forward(false), m_stdout_data(), m_stderr_data(),
+      m_stdin_forward(false), m_stdout_data(),
       m_profile_data_comm_mutex(), m_profile_data(), m_iohandler_sync(0),
       m_memory_cache(*this), m_allocated_memory_cache(*this),
       m_should_detach(false), m_next_event_action_up(), m_public_run_lock(),
@@ -4224,13 +4224,6 @@
                          new ProcessEventData(shared_from_this(), GetState()));
 }
 
-void Process::AppendSTDERR(const char *s, size_t len) {
-  std::lock_guard<std::recursive_mutex> guard(m_stdio_communication_mutex);
-  m_stderr_data.append(s, len);
-  BroadcastEventIfUnique(eBroadcastBitSTDERR,
-                         new ProcessEventData(shared_from_this(), GetState()));
-}
-
 void Process::BroadcastAsyncProfileData(const std::string &one_profile_data) {
   std::lock_guard<std::recursive_mutex> guard(m_profile_data_comm_mutex);
   m_profile_data.push_back(one_profile_data);
@@ -4299,22 +4292,7 @@
 }
 
 size_t Process::GetSTDERR(char *buf, size_t buf_size, Status &error) {
-  std::lock_guard<std::recursive_mutex> gaurd(m_stdio_communication_mutex);
-  size_t bytes_available = m_stderr_data.size();
-  if (bytes_available > 0) {
-    Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
-    LLDB_LOGF(log, "Process::GetSTDERR (buf = %p, size = %" PRIu64 ")",
-              static_cast<void *>(buf), static_cast<uint64_t>(buf_size));
-    if (bytes_available > buf_size) {
-      memcpy(buf, m_stderr_data.c_str(), buf_size);
-      m_stderr_data.erase(0, buf_size);
-      bytes_available = buf_size;
-    } else {
-      memcpy(buf, m_stderr_data.c_str(), bytes_available);
-      m_stderr_data.clear();
-    }
-  }
-  return bytes_available;
+  return 0; // not implemented.
 }
 
 void Process::STDIOReadThreadBytesReceived(void *baton, const void *src,