diff --git a/Makefile b/Makefile
index 62af57c4cb..cf915c10d6 100644
--- a/Makefile
+++ b/Makefile
@@ -250,6 +250,8 @@ obj/upb/%.lo: upb/%.cc | $$(@D)/.
 
 # Regenerating the auto-generated files in upb/.
 upb/descriptor/descriptor.pb: upb/descriptor/descriptor.proto
+	$(E) PROTOC upb/descriptor/descriptor.proto
+	$(Q) protoc upb/descriptor/descriptor.proto -oupb/descriptor/descriptor.pb
 
 # "genfiles" includes Proto schemas we need for tests
 # For the moment we check in the *.upbdefs.* generated files so that people
diff --git a/upb/bindings/googlepb/proto2.cc b/upb/bindings/googlepb/proto2.cc
index bfd5ba2f42..ebfedca25b 100644
--- a/upb/bindings/googlepb/proto2.cc
+++ b/upb/bindings/googlepb/proto2.cc
@@ -12,10 +12,10 @@
 
 #include <map>
 
-#include "upb/def.h"
 #include "upb/bindings/googlepb/proto1.int.h"
+#include "upb/def.h"
 #include "upb/handlers.h"
-#include "upb/shim/shim.h"
+#include "upb/msg.h"
 #include "upb/sink.h"
 
 namespace {
@@ -593,8 +593,8 @@ case goog::FieldDescriptor::cpptype:                                           \
         SetStartRepeatedField<T>(proto2_f, r, f, h);
         CHKRET(h->SetValueHandler<T>(f, UpbMakeHandlerT(AppendPrimitive<T>)));
       } else {
-        CHKRET(upb::Shim::Set(h, f, GetOffset(proto2_f, r),
-                              GetHasbit(proto2_f, r)));
+        CHKRET(upb_msg_setscalarhandler(h, f, GetOffset(proto2_f, r),
+                                        GetHasbit(proto2_f, r)));
       }
     }
   }
diff --git a/upb/msg.h b/upb/msg.h
index 912d6ac951..2d1a261590 100644
--- a/upb/msg.h
+++ b/upb/msg.h
@@ -32,8 +32,13 @@
 #ifdef __cplusplus
 
 namespace upb {
-class MessageLayout;
+class Array;
+class Map;
+class MapIterator;
 class MessageFactory;
+class MessageLayout;
+class Visitor;
+class VisitorPlan;
 }
 
 #endif
@@ -110,6 +115,9 @@ typedef union {
   int64_t i64;
   uint32_t u32;
   uint64_t u64;
+  const upb_map* map;
+  const upb_msg* msg;
+  const upb_array* arr;
   const void* ptr;
   struct {
     const char *ptr;
@@ -137,10 +145,10 @@ ACCESSORS(int32,  i32, int32_t)
 ACCESSORS(int64,  i64, int64_t)
 ACCESSORS(uint32, u32, uint32_t)
 ACCESSORS(uint64, u64, uint64_t)
-ACCESSORS(map,    ptr, const upb_map*)
-ACCESSORS(msg,    ptr, const upb_msg*)
+ACCESSORS(map,    map, const upb_map*)
+ACCESSORS(msg,    msg, const upb_msg*)
 ACCESSORS(ptr,    ptr, const void*)
-ACCESSORS(arr,    ptr, const upb_array*)
+ACCESSORS(arr,    arr, const upb_array*)
 
 #undef ACCESSORS