If you erase while iterating, remember to update the iterator.  Bug found by Carlo Kok.

llvm-svn: 191555
diff --git a/lldb/source/Symbol/Symtab.cpp b/lldb/source/Symbol/Symtab.cpp
index 27af698..d3ea9d6 100644
--- a/lldb/source/Symbol/Symtab.cpp
+++ b/lldb/source/Symbol/Symtab.cpp
@@ -682,7 +682,7 @@
             if (symbol_type == eSymbolTypeAny || m_symbols[*pos].GetType() == symbol_type)
                 ++pos;
             else
-                indexes.erase(pos);
+                pos = indexes.erase(pos);
         }
     }
     return indexes.size();
@@ -701,7 +701,7 @@
             if (symbol_type == eSymbolTypeAny || m_symbols[*pos].GetType() == symbol_type)
                 ++pos;
             else
-                indexes.erase(pos);
+                pos = indexes.erase(pos);
         }
     }
     return indexes.size();