Use ranged-for instead of indexed iteration

Author: tautschnig

src/goto-programs/goto_convert.cpp

@@ -149,12 +149,15 @@ void goto_convertt::finish_gotos(goto_programt &dest, const irep_idt &mode)
       bool stack_is_prefix=true;
       if(label_stack.size()>goto_stack.size())
         stack_is_prefix=false;
-      for(std::size_t i=0, ilim=label_stack.size();
-          i!=ilim && stack_is_prefix;
-          ++i)
+      auto label_stack_it = label_stack.begin();
+      for(const auto &g : goto_stack)
       {
-        if(goto_stack[i]!=label_stack[i])
+        if(!stack_is_prefix || label_stack_it == label_stack.end())
+          break;
+        else if(g != *label_stack_it)
           stack_is_prefix=false;
+
+        ++label_stack_it;
       }
 
       if(!stack_is_prefix)