Typedef names are symbols

remove_internal_symbols must get to see typedef names so as not to remove type
symbols that constitute typedef names.

Follow-up to 99067de

Author: tautschnig

src/goto-cc/compile.cpp

@@ -714,6 +714,7 @@ void compilet::convert_symbols(goto_functionst &dest)
 
       if(s_it->second.type.id()==ID_code &&
          !s_it->second.is_macro &&
+         !s_it->second.is_type &&
           s_it->second.value.id()!="compiled" &&
           s_it->second.value.is_not_nil())
       {

src/goto-programs/read_goto_binary.cpp

@@ -302,7 +302,7 @@ static bool link_functions(
   rename_symbolt macro_application;
 
   forall_symbols(it, dest_symbol_table.symbols)
-    if(it->second.is_macro)
+    if(it->second.is_macro && !it->second.is_type)
     {
       const symbolt &symbol=it->second;
 

src/util/find_symbols.cpp

@@ -124,6 +124,10 @@ void find_symbols(kindt kind, const typet &src, find_symbols_sett &dest)
 
     forall_subtypes(it, src)
       find_symbols(kind, *it, dest);
+
+    const irep_idt &typedef_name=src.get(ID_C_typedef);
+    if(!typedef_name.empty())
+      dest.insert(typedef_name);
   }
 
   if(src.id()==ID_struct ||