Index: lldb/trunk/include/lldb/Target/Target.h
===================================================================
--- lldb/trunk/include/lldb/Target/Target.h
+++ lldb/trunk/include/lldb/Target/Target.h
@@ -1071,6 +1071,9 @@
     bool
     SetArchitecture (const ArchSpec &arch_spec);
 
+    bool
+    MergeArchitecture (const ArchSpec &arch_spec);
+
     Debugger &
     GetDebugger ()
     {
Index: lldb/trunk/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
===================================================================
--- lldb/trunk/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ lldb/trunk/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -939,16 +939,17 @@
 
             if (m_gdb_comm.SendPacketAndWaitForResponse("?", 1, m_last_stop_packet, false) == GDBRemoteCommunication::PacketResult::Success)
             {
-                if (!m_target.GetArchitecture().IsValid()) 
+                const ArchSpec &process_arch = m_gdb_comm.GetProcessArchitecture();
+
+                if (process_arch.IsValid())
                 {
-                    if (m_gdb_comm.GetProcessArchitecture().IsValid())
-                    {
-                        m_target.SetArchitecture(m_gdb_comm.GetProcessArchitecture());
-                    }
-                    else
-                    {
-                        m_target.SetArchitecture(m_gdb_comm.GetHostArchitecture());
-                    }
+                    m_target.MergeArchitecture(process_arch);
+                }
+                else
+                {
+                    const ArchSpec &host_arch = m_gdb_comm.GetHostArchitecture();
+                    if (host_arch.IsValid())
+                        m_target.MergeArchitecture(host_arch);
                 }
 
                 SetPrivateState (SetThreadStopInfo (m_last_stop_packet));
Index: lldb/trunk/source/Target/Target.cpp
===================================================================
--- lldb/trunk/source/Target/Target.cpp
+++ lldb/trunk/source/Target/Target.cpp
@@ -1189,6 +1189,30 @@
     return false;
 }
 
+bool
+Target::MergeArchitecture (const ArchSpec &arch_spec)
+{
+    if (arch_spec.IsValid())
+    {
+        if (m_arch.IsCompatibleMatch(arch_spec))
+        {
+            // The current target arch is compatible with "arch_spec", see if we
+            // can improve our current architecture using bits from "arch_spec"
+
+            // Merge bits from arch_spec into "merged_arch" and set our architecture
+            ArchSpec merged_arch (m_arch);
+            merged_arch.MergeFrom (arch_spec);
+            return SetArchitecture(merged_arch);
+        }
+        else
+        {
+            // The new architecture is different, we just need to replace it
+            return SetArchitecture(arch_spec);
+        }
+    }
+    return false;
+}
+
 void
 Target::WillClearList (const ModuleList& module_list)
 {