fixup: Do inline entry methods manually

docs/GroupDefs.hpp

@@ -1025,6 +1025,16 @@ The `receive_data` function always takes a `ReceiveTag`, which is set in the
 actions `inbox_tags` type alias as described above.  The first argument is the
 temporal identifier, and the second is the data to be sent.
 
+Normally when remote functions are invoked they go through the Charm++ runtime
+system, which adds some overhead. The `receive_data` function elides the call to
+the Charm++ RTS for calls into array components. Charm++ refers to
+these types of remote calls as "inline entry methods". With the Charm++ method
+of eliding the RTS the code becomes susceptible to stack overflows because
+of infinite recursion. The `receive_data` function is limited to at most 64 RTS
+elided calls, though in practice reaching this limit is rare. When the limit is
+reached the remote method invocation is done through the RTS instead of being
+elided.
+
 #### 3. Reduction %Actions
 
 Finally, there are reduction actions which are used when reducing data over an

src/Parallel/Invoke.hpp

@@ -52,6 +52,8 @@ void receive_data(Proxy&& proxy, typename ReceiveTag::temporal_id temporal_id,
                   ReceiveDataType&& receive_data,
                   const bool enable_if_disabled) noexcept {
   auto* obj = proxy.ckLocal();
+  // Only elide the Charm++ RTS if the object is local and if we won't blow the
+  // stack by having too many recursive function calls.
   if (obj != nullptr and not detail::max_inline_entry_methods_reached()) {
     obj->template receive_data<ReceiveTag>(
         std::move(temporal_id), std::forward<ReceiveDataType>(receive_data),
@@ -69,6 +71,8 @@ template <
 void receive_data(Proxy&& proxy, typename ReceiveTag::temporal_id temporal_id,
                   ReceiveDataType&& receive_data) noexcept {
   auto* obj = proxy.ckLocal();
+  // Only elide the Charm++ RTS if the object is local and if we won't blow the
+  // stack by having too many recursive function calls.
   if (obj != nullptr and not detail::max_inline_entry_methods_reached()) {
     obj->template receive_data<ReceiveTag>(
         std::move(temporal_id), std::forward<ReceiveDataType>(receive_data));