<rdar://problem/12406088> Fixing a crasher with adding a regex command, due to accessing a shared pointer without first checking for NULL


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@164950 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Interpreter/CommandInterpreter.cpp b/source/Interpreter/CommandInterpreter.cpp
index eed4038..44ba511 100644
--- a/source/Interpreter/CommandInterpreter.cpp
+++ b/source/Interpreter/CommandInterpreter.cpp
@@ -624,12 +624,10 @@
     if (name && name[0])
     {
         std::string name_sstr(name);
-        if (!can_replace)
-        {
-            if (m_command_dict.find (name_sstr) != m_command_dict.end())
-                return false;
-        }
-        if (m_command_dict[name_sstr]->IsRemovable() == false)
+        bool found = (m_command_dict.find (name_sstr) != m_command_dict.end());
+        if (found && !can_replace)
+            return false;
+        if (found && m_command_dict[name_sstr]->IsRemovable() == false)
             return false;
         m_command_dict[name_sstr] = cmd_sp;
         return true;