diff --git a/upb/port/def.inc b/upb/port/def.inc
index b23b406992..dfcbce6a5a 100644
--- a/upb/port/def.inc
+++ b/upb/port/def.inc
@@ -302,3 +302,13 @@ void __asan_unpoison_memory_region(void const volatile *addr, size_t size);
 #else
 #define UPB_DEPRECATED
 #endif
+
+// begin:google_only
+// #define UPB_IS_GOOGLE3
+// end:google_only
+
+#if defined(UPB_IS_GOOGLE3)
+#define UPB_DESC(sym) proto2_##sym
+#else
+#define UPB_DESC(sym) google_protobuf_##sym
+#endif
diff --git a/upb/port/undef.inc b/upb/port/undef.inc
index 8b779502c6..fd201e321c 100644
--- a/upb/port/undef.inc
+++ b/upb/port/undef.inc
@@ -64,3 +64,5 @@
 #undef UPB_TREAT_PROTO2_ENUMS_LIKE_PROTO3
 #undef UPB_DEPRECATED
 #undef UPB_GNUC_MIN
+#undef UPB_DESC
+#undef UPB_IS_GOOGLE3
diff --git a/upb/reflection/def_builder_internal.h b/upb/reflection/def_builder_internal.h
index f72b36c278..ad43135020 100644
--- a/upb/reflection/def_builder_internal.h
+++ b/upb/reflection/def_builder_internal.h
@@ -37,17 +37,17 @@
 
 // We want to copy the options verbatim into the destination options proto.
 // We use serialize+parse as our deep copy.
-#define UPB_DEF_SET_OPTIONS(target, desc_type, options_type, proto)          \
-  if (google_protobuf_##desc_type##_has_options(proto)) {                             \
-    size_t size;                                                             \
-    char* pb = google_protobuf_##options_type##_serialize(                            \
-        google_protobuf_##desc_type##_options(proto), ctx->tmp_arena, &size);         \
-    if (!pb) _upb_DefBuilder_OomErr(ctx);                                    \
-    target =                                                                 \
-        google_protobuf_##options_type##_parse(pb, size, _upb_DefBuilder_Arena(ctx)); \
-    if (!target) _upb_DefBuilder_OomErr(ctx);                                \
-  } else {                                                                   \
-    target = (const google_protobuf_##options_type*)kUpbDefOptDefault;                \
+#define UPB_DEF_SET_OPTIONS(target, desc_type, options_type, proto)           \
+  if (UPB_DESC(desc_type##_has_options)(proto)) {                             \
+    size_t size;                                                              \
+    char* pb = UPB_DESC(options_type##_serialize)(                            \
+        UPB_DESC(desc_type##_options)(proto), ctx->tmp_arena, &size);         \
+    if (!pb) _upb_DefBuilder_OomErr(ctx);                                     \
+    target =                                                                  \
+        UPB_DESC(options_type##_parse)(pb, size, _upb_DefBuilder_Arena(ctx)); \
+    if (!target) _upb_DefBuilder_OomErr(ctx);                                 \
+  } else {                                                                    \
+    target = (const UPB_DESC(options_type)*)kUpbDefOptDefault;                \
   }
 
 #ifdef __cplusplus
diff --git a/upb/reflection/def_pool.c b/upb/reflection/def_pool.c
index a088873034..3f88dc5cd5 100644
--- a/upb/reflection/def_pool.c
+++ b/upb/reflection/def_pool.c
@@ -281,9 +281,9 @@ static void remove_filedef(upb_DefPool* s, upb_FileDef* file) {
 }
 
 static const upb_FileDef* _upb_DefPool_AddFile(
-    upb_DefPool* s, const google_protobuf_FileDescriptorProto* file_proto,
+    upb_DefPool* s, const UPB_DESC(FileDescriptorProto) * file_proto,
     const upb_MiniTableFile* layout, upb_Status* status) {
-  const upb_StringView name = google_protobuf_FileDescriptorProto_name(file_proto);
+  const upb_StringView name = UPB_DESC(FileDescriptorProto_name)(file_proto);
 
   if (name.size == 0) {
     upb_Status_SetErrorFormat(status,
@@ -335,9 +335,10 @@ static const upb_FileDef* _upb_DefPool_AddFile(
   return ctx.file;
 }
 
-const upb_FileDef* upb_DefPool_AddFile(
-    upb_DefPool* s, const google_protobuf_FileDescriptorProto* file_proto,
-    upb_Status* status) {
+const upb_FileDef* upb_DefPool_AddFile(upb_DefPool* s,
+                                       const UPB_DESC(FileDescriptorProto) *
+                                           file_proto,
+                                       upb_Status* status) {
   return _upb_DefPool_AddFile(s, file_proto, NULL, status);
 }
 
@@ -346,7 +347,7 @@ bool _upb_DefPool_LoadDefInitEx(upb_DefPool* s, const _upb_DefPool_Init* init,
   /* Since this function should never fail (it would indicate a bug in upb) we
    * print errors to stderr instead of returning error status to the user. */
   _upb_DefPool_Init** deps = init->deps;
-  google_protobuf_FileDescriptorProto* file;
+  UPB_DESC(FileDescriptorProto) * file;
   upb_Arena* arena;
   upb_Status status;
 
@@ -362,7 +363,7 @@ bool _upb_DefPool_LoadDefInitEx(upb_DefPool* s, const _upb_DefPool_Init* init,
     if (!_upb_DefPool_LoadDefInitEx(s, *deps, rebuild_minitable)) goto err;
   }
 
-  file = google_protobuf_FileDescriptorProto_parse_ex(
+  file = UPB_DESC(FileDescriptorProto_parse_ex)(
       init->descriptor.data, init->descriptor.size, NULL,
       kUpb_DecodeOption_AliasString, arena);
   s->bytes_loaded += init->descriptor.size;
diff --git a/upb/reflection/def_pool.h b/upb/reflection/def_pool.h
index aef54ab356..157ff3aa83 100644
--- a/upb/reflection/def_pool.h
+++ b/upb/reflection/def_pool.h
@@ -87,9 +87,10 @@ const upb_ServiceDef* upb_DefPool_FindServiceByNameWithSize(
 const upb_FileDef* upb_DefPool_FindFileContainingSymbol(const upb_DefPool* s,
                                                         const char* name);
 
-const upb_FileDef* upb_DefPool_AddFile(
-    upb_DefPool* s, const google_protobuf_FileDescriptorProto* file_proto,
-    upb_Status* status);
+const upb_FileDef* upb_DefPool_AddFile(upb_DefPool* s,
+                                       const UPB_DESC(FileDescriptorProto) *
+                                           file_proto,
+                                       upb_Status* status);
 
 const upb_ExtensionRegistry* upb_DefPool_ExtensionRegistry(
     const upb_DefPool* s);
diff --git a/upb/reflection/enum_def.c b/upb/reflection/enum_def.c
index d3eb6af105..bb91a1efac 100644
--- a/upb/reflection/enum_def.c
+++ b/upb/reflection/enum_def.c
@@ -41,7 +41,7 @@
 #include "upb/port/def.inc"
 
 struct upb_EnumDef {
-  const google_protobuf_EnumOptions* opts;
+  const UPB_DESC(EnumOptions) * opts;
   const upb_MiniTableEnum* layout;  // Only for proto2.
   const upb_FileDef* file;
   const upb_MessageDef* containing_type;  // Could be merged with "file".
@@ -89,7 +89,7 @@ bool _upb_EnumDef_Insert(upb_EnumDef* e, upb_EnumValueDef* v, upb_Arena* a) {
   return true;
 }
 
-const google_protobuf_EnumOptions* upb_EnumDef_Options(const upb_EnumDef* e) {
+const UPB_DESC(EnumOptions) * upb_EnumDef_Options(const upb_EnumDef* e) {
   return e->opts;
 }
 
@@ -237,10 +237,10 @@ static upb_StringView* _upb_EnumReservedNames_New(
 }
 
 static void create_enumdef(upb_DefBuilder* ctx, const char* prefix,
-                           const google_protobuf_EnumDescriptorProto* enum_proto,
+                           const UPB_DESC(EnumDescriptorProto) * enum_proto,
                            upb_EnumDef* e) {
-  const google_protobuf_EnumValueDescriptorProto* const* values;
-  const google_protobuf_EnumDescriptorProto_EnumReservedRange* const* res_ranges;
+  const UPB_DESC(EnumValueDescriptorProto)* const* values;
+  const UPB_DESC(EnumDescriptorProto_EnumReservedRange)* const* res_ranges;
   const upb_StringView* res_names;
   upb_StringView name;
   size_t n_value, n_res_range, n_res_name;
@@ -248,14 +248,14 @@ static void create_enumdef(upb_DefBuilder* ctx, const char* prefix,
   // Must happen before _upb_DefBuilder_Add()
   e->file = _upb_DefBuilder_File(ctx);
 
-  name = google_protobuf_EnumDescriptorProto_name(enum_proto);
+  name = UPB_DESC(EnumDescriptorProto_name)(enum_proto);
   _upb_DefBuilder_CheckIdentNotFull(ctx, name);
 
   e->full_name = _upb_DefBuilder_MakeFullName(ctx, prefix, name);
   _upb_DefBuilder_Add(ctx, e->full_name,
                       _upb_DefType_Pack(e, UPB_DEFTYPE_ENUM));
 
-  values = google_protobuf_EnumDescriptorProto_value(enum_proto, &n_value);
+  values = UPB_DESC(EnumDescriptorProto_value)(enum_proto, &n_value);
 
   bool ok = upb_strtable_init(&e->ntoi, n_value, ctx->arena);
   if (!ok) _upb_DefBuilder_OomErr(ctx);
@@ -274,11 +274,12 @@ static void create_enumdef(upb_DefBuilder* ctx, const char* prefix,
   }
 
   res_ranges =
-      google_protobuf_EnumDescriptorProto_reserved_range(enum_proto, &n_res_range);
+      UPB_DESC(EnumDescriptorProto_reserved_range)(enum_proto, &n_res_range);
   e->res_range_count = n_res_range;
   e->res_ranges = _upb_EnumReservedRanges_New(ctx, n_res_range, res_ranges, e);
 
-  res_names = google_protobuf_EnumDescriptorProto_reserved_name(enum_proto, &n_res_name);
+  res_names =
+      UPB_DESC(EnumDescriptorProto_reserved_name)(enum_proto, &n_res_name);
   e->res_name_count = n_res_name;
   e->res_names = _upb_EnumReservedNames_New(ctx, n_res_name, res_names);
 
@@ -298,9 +299,10 @@ static void create_enumdef(upb_DefBuilder* ctx, const char* prefix,
   }
 }
 
-upb_EnumDef* _upb_EnumDefs_New(upb_DefBuilder* ctx, int n,
-                               const google_protobuf_EnumDescriptorProto* const* protos,
-                               const upb_MessageDef* containing_type) {
+upb_EnumDef* _upb_EnumDefs_New(
+    upb_DefBuilder* ctx, int n,
+    const UPB_DESC(EnumDescriptorProto) * const* protos,
+    const upb_MessageDef* containing_type) {
   _upb_DefType_CheckPadding(sizeof(upb_EnumDef));
 
   // If a containing type is defined then get the full name from that.
diff --git a/upb/reflection/enum_def.h b/upb/reflection/enum_def.h
index 20a07a9587..f115e88923 100644
--- a/upb/reflection/enum_def.h
+++ b/upb/reflection/enum_def.h
@@ -59,7 +59,7 @@ bool upb_EnumDef_MiniDescriptorEncode(const upb_EnumDef* e, upb_Arena* a,
                                       upb_StringView* out);
 
 const char* upb_EnumDef_Name(const upb_EnumDef* e);
-const google_protobuf_EnumOptions* upb_EnumDef_Options(const upb_EnumDef* e);
+const UPB_DESC(EnumOptions) * upb_EnumDef_Options(const upb_EnumDef* e);
 
 upb_StringView upb_EnumDef_ReservedName(const upb_EnumDef* e, int i);
 int upb_EnumDef_ReservedNameCount(const upb_EnumDef* e);
diff --git a/upb/reflection/enum_def_internal.h b/upb/reflection/enum_def_internal.h
index 01529d6c32..41f9958683 100644
--- a/upb/reflection/enum_def_internal.h
+++ b/upb/reflection/enum_def_internal.h
@@ -42,9 +42,10 @@ bool _upb_EnumDef_Insert(upb_EnumDef* e, upb_EnumValueDef* v, upb_Arena* a);
 const upb_MiniTableEnum* _upb_EnumDef_MiniTable(const upb_EnumDef* e);
 
 // Allocate and initialize an array of |n| enum defs.
-upb_EnumDef* _upb_EnumDefs_New(upb_DefBuilder* ctx, int n,
-                               const google_protobuf_EnumDescriptorProto* const* protos,
-                               const upb_MessageDef* containing_type);
+upb_EnumDef* _upb_EnumDefs_New(
+    upb_DefBuilder* ctx, int n,
+    const UPB_DESC(EnumDescriptorProto) * const* protos,
+    const upb_MessageDef* containing_type);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/enum_reserved_range.c b/upb/reflection/enum_reserved_range.c
index ceda4cd071..f6e2268668 100644
--- a/upb/reflection/enum_reserved_range.c
+++ b/upb/reflection/enum_reserved_range.c
@@ -54,16 +54,16 @@ int32_t upb_EnumReservedRange_End(const upb_EnumReservedRange* r) {
 
 upb_EnumReservedRange* _upb_EnumReservedRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_EnumDescriptorProto_EnumReservedRange* const* protos,
+    const UPB_DESC(EnumDescriptorProto_EnumReservedRange) * const* protos,
     const upb_EnumDef* e) {
   upb_EnumReservedRange* r =
       _upb_DefBuilder_Alloc(ctx, sizeof(upb_EnumReservedRange) * n);
 
   for (int i = 0; i < n; i++) {
     const int32_t start =
-        google_protobuf_EnumDescriptorProto_EnumReservedRange_start(protos[i]);
+        UPB_DESC(EnumDescriptorProto_EnumReservedRange_start)(protos[i]);
     const int32_t end =
-        google_protobuf_EnumDescriptorProto_EnumReservedRange_end(protos[i]);
+        UPB_DESC(EnumDescriptorProto_EnumReservedRange_end)(protos[i]);
 
     // A full validation would also check that each range is disjoint, and that
     // none of the fields overlap with the extension ranges, but we are just
diff --git a/upb/reflection/enum_reserved_range_internal.h b/upb/reflection/enum_reserved_range_internal.h
index e3aa2ede26..869f3b60ca 100644
--- a/upb/reflection/enum_reserved_range_internal.h
+++ b/upb/reflection/enum_reserved_range_internal.h
@@ -43,7 +43,7 @@ upb_EnumReservedRange* _upb_EnumReservedRange_At(const upb_EnumReservedRange* r,
 // Allocate and initialize an array of |n| reserved ranges owned by |e|.
 upb_EnumReservedRange* _upb_EnumReservedRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_EnumDescriptorProto_EnumReservedRange* const* protos,
+    const UPB_DESC(EnumDescriptorProto_EnumReservedRange) * const* protos,
     const upb_EnumDef* e);
 
 #ifdef __cplusplus
diff --git a/upb/reflection/enum_value_def.c b/upb/reflection/enum_value_def.c
index afa1f0d73a..70d2f1a45a 100644
--- a/upb/reflection/enum_value_def.c
+++ b/upb/reflection/enum_value_def.c
@@ -35,7 +35,7 @@
 #include "upb/port/def.inc"
 
 struct upb_EnumValueDef {
-  const google_protobuf_EnumValueOptions* opts;
+  const UPB_DESC(EnumValueOptions) * opts;
   const upb_EnumDef* parent;
   const char* full_name;
   int32_t number;
@@ -66,8 +66,8 @@ const upb_EnumValueDef** _upb_EnumValueDefs_Sorted(const upb_EnumValueDef* v,
   return (const upb_EnumValueDef**)out;
 }
 
-const google_protobuf_EnumValueOptions* upb_EnumValueDef_Options(
-    const upb_EnumValueDef* v) {
+const UPB_DESC(EnumValueOptions) *
+    upb_EnumValueDef_Options(const upb_EnumValueDef* v) {
   return v->opts;
 }
 
@@ -95,13 +95,14 @@ uint32_t upb_EnumValueDef_Index(const upb_EnumValueDef* v) {
 }
 
 static void create_enumvaldef(upb_DefBuilder* ctx, const char* prefix,
-                              const google_protobuf_EnumValueDescriptorProto* val_proto,
+                              const UPB_DESC(EnumValueDescriptorProto) *
+                                  val_proto,
                               upb_EnumDef* e, upb_EnumValueDef* v) {
-  upb_StringView name = google_protobuf_EnumValueDescriptorProto_name(val_proto);
+  upb_StringView name = UPB_DESC(EnumValueDescriptorProto_name)(val_proto);
 
   v->parent = e;  // Must happen prior to _upb_DefBuilder_Add()
   v->full_name = _upb_DefBuilder_MakeFullName(ctx, prefix, name);
-  v->number = google_protobuf_EnumValueDescriptorProto_number(val_proto);
+  v->number = UPB_DESC(EnumValueDescriptorProto_number)(val_proto);
   _upb_DefBuilder_Add(ctx, v->full_name,
                       _upb_DefType_Pack(v, UPB_DEFTYPE_ENUMVAL));
 
@@ -115,7 +116,7 @@ static void create_enumvaldef(upb_DefBuilder* ctx, const char* prefix,
 // Allocate and initialize an array of |n| enum value defs owned by |e|.
 upb_EnumValueDef* _upb_EnumValueDefs_New(
     upb_DefBuilder* ctx, const char* prefix, int n,
-    const google_protobuf_EnumValueDescriptorProto* const* protos, upb_EnumDef* e,
+    const UPB_DESC(EnumValueDescriptorProto) * const* protos, upb_EnumDef* e,
     bool* is_sorted) {
   _upb_DefType_CheckPadding(sizeof(upb_EnumValueDef));
 
diff --git a/upb/reflection/enum_value_def.h b/upb/reflection/enum_value_def.h
index fd43610d9f..9f01edbff0 100644
--- a/upb/reflection/enum_value_def.h
+++ b/upb/reflection/enum_value_def.h
@@ -45,8 +45,8 @@ bool upb_EnumValueDef_HasOptions(const upb_EnumValueDef* v);
 uint32_t upb_EnumValueDef_Index(const upb_EnumValueDef* v);
 const char* upb_EnumValueDef_Name(const upb_EnumValueDef* v);
 int32_t upb_EnumValueDef_Number(const upb_EnumValueDef* v);
-const google_protobuf_EnumValueOptions* upb_EnumValueDef_Options(
-    const upb_EnumValueDef* v);
+const UPB_DESC(EnumValueOptions) *
+    upb_EnumValueDef_Options(const upb_EnumValueDef* v);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/enum_value_def_internal.h b/upb/reflection/enum_value_def_internal.h
index c073ce8885..09f0644da0 100644
--- a/upb/reflection/enum_value_def_internal.h
+++ b/upb/reflection/enum_value_def_internal.h
@@ -42,7 +42,7 @@ upb_EnumValueDef* _upb_EnumValueDef_At(const upb_EnumValueDef* v, int i);
 // Allocate and initialize an array of |n| enum value defs owned by |e|.
 upb_EnumValueDef* _upb_EnumValueDefs_New(
     upb_DefBuilder* ctx, const char* prefix, int n,
-    const google_protobuf_EnumValueDescriptorProto* const* protos, upb_EnumDef* e,
+    const UPB_DESC(EnumValueDescriptorProto) * const* protos, upb_EnumDef* e,
     bool* is_sorted);
 
 const upb_EnumValueDef** _upb_EnumValueDefs_Sorted(const upb_EnumValueDef* v,
diff --git a/upb/reflection/extension_range.c b/upb/reflection/extension_range.c
index 25a4246023..d7dfebdd62 100644
--- a/upb/reflection/extension_range.c
+++ b/upb/reflection/extension_range.c
@@ -34,7 +34,7 @@
 #include "upb/port/def.inc"
 
 struct upb_ExtensionRange {
-  const google_protobuf_ExtensionRangeOptions* opts;
+  const UPB_DESC(ExtensionRangeOptions) * opts;
   int32_t start;
   int32_t end;
 };
@@ -43,8 +43,8 @@ upb_ExtensionRange* _upb_ExtensionRange_At(const upb_ExtensionRange* r, int i) {
   return (upb_ExtensionRange*)&r[i];
 }
 
-const google_protobuf_ExtensionRangeOptions* upb_ExtensionRange_Options(
-    const upb_ExtensionRange* r) {
+const UPB_DESC(ExtensionRangeOptions) *
+    upb_ExtensionRange_Options(const upb_ExtensionRange* r) {
   return r->opts;
 }
 
@@ -60,19 +60,19 @@ int32_t upb_ExtensionRange_End(const upb_ExtensionRange* r) { return r->end; }
 
 upb_ExtensionRange* _upb_ExtensionRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_DescriptorProto_ExtensionRange* const* protos,
+    const UPB_DESC(DescriptorProto_ExtensionRange) * const* protos,
     const upb_MessageDef* m) {
   upb_ExtensionRange* r =
       _upb_DefBuilder_Alloc(ctx, sizeof(upb_ExtensionRange) * n);
 
   for (int i = 0; i < n; i++) {
     const int32_t start =
-        google_protobuf_DescriptorProto_ExtensionRange_start(protos[i]);
-    const int32_t end = google_protobuf_DescriptorProto_ExtensionRange_end(protos[i]);
-    const int32_t max =
-        google_protobuf_MessageOptions_message_set_wire_format(upb_MessageDef_Options(m))
-            ? INT32_MAX
-            : kUpb_MaxFieldNumber + 1;
+        UPB_DESC(DescriptorProto_ExtensionRange_start)(protos[i]);
+    const int32_t end = UPB_DESC(DescriptorProto_ExtensionRange_end)(protos[i]);
+    const int32_t max = UPB_DESC(MessageOptions_message_set_wire_format)(
+                            upb_MessageDef_Options(m))
+                            ? INT32_MAX
+                            : kUpb_MaxFieldNumber + 1;
 
     // A full validation would also check that each range is disjoint, and that
     // none of the fields overlap with the extension ranges, but we are just
diff --git a/upb/reflection/extension_range.h b/upb/reflection/extension_range.h
index 004f9a8bb7..c8d56be504 100644
--- a/upb/reflection/extension_range.h
+++ b/upb/reflection/extension_range.h
@@ -43,8 +43,8 @@ int32_t upb_ExtensionRange_Start(const upb_ExtensionRange* r);
 int32_t upb_ExtensionRange_End(const upb_ExtensionRange* r);
 
 bool upb_ExtensionRange_HasOptions(const upb_ExtensionRange* r);
-const google_protobuf_ExtensionRangeOptions* upb_ExtensionRange_Options(
-    const upb_ExtensionRange* r);
+const UPB_DESC(ExtensionRangeOptions) *
+    upb_ExtensionRange_Options(const upb_ExtensionRange* r);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/extension_range_internal.h b/upb/reflection/extension_range_internal.h
index 2aa643b03b..fde3d941f3 100644
--- a/upb/reflection/extension_range_internal.h
+++ b/upb/reflection/extension_range_internal.h
@@ -42,7 +42,7 @@ upb_ExtensionRange* _upb_ExtensionRange_At(const upb_ExtensionRange* r, int i);
 // Allocate and initialize an array of |n| extension ranges owned by |m|.
 upb_ExtensionRange* _upb_ExtensionRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_DescriptorProto_ExtensionRange* const* protos,
+    const UPB_DESC(DescriptorProto_ExtensionRange) * const* protos,
     const upb_MessageDef* m);
 
 #ifdef __cplusplus
diff --git a/upb/reflection/field_def.c b/upb/reflection/field_def.c
index 11d5e403f5..ecf8e32b5c 100644
--- a/upb/reflection/field_def.c
+++ b/upb/reflection/field_def.c
@@ -52,7 +52,7 @@ typedef struct {
 } str_t;
 
 struct upb_FieldDef {
-  const google_protobuf_FieldOptions* opts;
+  const UPB_DESC(FieldOptions) * opts;
   const upb_FileDef* file;
   const upb_MessageDef* msgdef;
   const char* full_name;
@@ -73,7 +73,7 @@ struct upb_FieldDef {
   union {
     const upb_MessageDef* msgdef;
     const upb_EnumDef* enumdef;
-    const google_protobuf_FieldDescriptorProto* unresolved;
+    const UPB_DESC(FieldDescriptorProto) * unresolved;
   } sub;
   uint32_t number_;
   uint16_t index_;
@@ -94,7 +94,7 @@ upb_FieldDef* _upb_FieldDef_At(const upb_FieldDef* f, int i) {
   return (upb_FieldDef*)&f[i];
 }
 
-const google_protobuf_FieldOptions* upb_FieldDef_Options(const upb_FieldDef* f) {
+const UPB_DESC(FieldOptions) * upb_FieldDef_Options(const upb_FieldDef* f) {
   return f->opts;
 }
 
@@ -549,22 +549,23 @@ static void set_default_default(upb_DefBuilder* ctx, upb_FieldDef* f) {
 }
 
 static void _upb_FieldDef_Create(upb_DefBuilder* ctx, const char* prefix,
-                                 const google_protobuf_FieldDescriptorProto* field_proto,
+                                 const UPB_DESC(FieldDescriptorProto) *
+                                     field_proto,
                                  upb_MessageDef* m, upb_FieldDef* f) {
   // Must happen before _upb_DefBuilder_Add()
   f->file = _upb_DefBuilder_File(ctx);
 
-  if (!google_protobuf_FieldDescriptorProto_has_name(field_proto)) {
+  if (!UPB_DESC(FieldDescriptorProto_has_name)(field_proto)) {
     _upb_DefBuilder_Errf(ctx, "field has no name");
   }
 
-  const upb_StringView name = google_protobuf_FieldDescriptorProto_name(field_proto);
+  const upb_StringView name = UPB_DESC(FieldDescriptorProto_name)(field_proto);
   _upb_DefBuilder_CheckIdentNotFull(ctx, name);
 
-  f->has_json_name_ = google_protobuf_FieldDescriptorProto_has_json_name(field_proto);
+  f->has_json_name_ = UPB_DESC(FieldDescriptorProto_has_json_name)(field_proto);
   if (f->has_json_name_) {
     const upb_StringView sv =
-        google_protobuf_FieldDescriptorProto_json_name(field_proto);
+        UPB_DESC(FieldDescriptorProto_json_name)(field_proto);
     f->json_name = upb_strdup2(sv.data, sv.size, ctx->arena);
   } else {
     f->json_name = make_json_name(name.data, name.size, ctx->arena);
@@ -572,18 +573,18 @@ static void _upb_FieldDef_Create(upb_DefBuilder* ctx, const char* prefix,
   if (!f->json_name) _upb_DefBuilder_OomErr(ctx);
 
   f->full_name = _upb_DefBuilder_MakeFullName(ctx, prefix, name);
-  f->label_ = (int)google_protobuf_FieldDescriptorProto_label(field_proto);
-  f->number_ = google_protobuf_FieldDescriptorProto_number(field_proto);
+  f->label_ = (int)UPB_DESC(FieldDescriptorProto_label)(field_proto);
+  f->number_ = UPB_DESC(FieldDescriptorProto_number)(field_proto);
   f->proto3_optional_ =
-      google_protobuf_FieldDescriptorProto_proto3_optional(field_proto);
+      UPB_DESC(FieldDescriptorProto_proto3_optional)(field_proto);
   f->msgdef = m;
   f->scope.oneof = NULL;
 
-  const bool has_type = google_protobuf_FieldDescriptorProto_has_type(field_proto);
+  const bool has_type = UPB_DESC(FieldDescriptorProto_has_type)(field_proto);
   const bool has_type_name =
-      google_protobuf_FieldDescriptorProto_has_type_name(field_proto);
+      UPB_DESC(FieldDescriptorProto_has_type_name)(field_proto);
 
-  f->type_ = (int)google_protobuf_FieldDescriptorProto_type(field_proto);
+  f->type_ = (int)UPB_DESC(FieldDescriptorProto_type)(field_proto);
 
   if (has_type) {
     switch (f->type_) {
@@ -628,8 +629,9 @@ static void _upb_FieldDef_Create(upb_DefBuilder* ctx, const char* prefix,
                          f->full_name);
   }
 
-  if (google_protobuf_FieldDescriptorProto_has_oneof_index(field_proto)) {
-    uint32_t oneof_index = google_protobuf_FieldDescriptorProto_oneof_index(field_proto);
+  if (UPB_DESC(FieldDescriptorProto_has_oneof_index)(field_proto)) {
+    uint32_t oneof_index =
+        UPB_DESC(FieldDescriptorProto_oneof_index)(field_proto);
 
     if (upb_FieldDef_Label(f) != kUpb_Label_Optional) {
       _upb_DefBuilder_Errf(ctx, "fields in oneof must have OPTIONAL label (%s)",
@@ -654,8 +656,8 @@ static void _upb_FieldDef_Create(upb_DefBuilder* ctx, const char* prefix,
 
   UPB_DEF_SET_OPTIONS(f->opts, FieldDescriptorProto, FieldOptions, field_proto);
 
-  if (google_protobuf_FieldOptions_has_packed(f->opts)) {
-    f->is_packed_ = google_protobuf_FieldOptions_packed(f->opts);
+  if (UPB_DESC(FieldOptions_has_packed)(f->opts)) {
+    f->is_packed_ = UPB_DESC(FieldOptions_packed)(f->opts);
   } else {
     // Repeated fields default to packed for proto3 only.
     f->is_packed_ = upb_FieldDef_IsPrimitive(f) &&
@@ -664,14 +666,14 @@ static void _upb_FieldDef_Create(upb_DefBuilder* ctx, const char* prefix,
   }
 }
 
-static void _upb_FieldDef_CreateExt(
-    upb_DefBuilder* ctx, const char* prefix,
-    const google_protobuf_FieldDescriptorProto* field_proto, upb_MessageDef* m,
-    upb_FieldDef* f) {
+static void _upb_FieldDef_CreateExt(upb_DefBuilder* ctx, const char* prefix,
+                                    const UPB_DESC(FieldDescriptorProto) *
+                                        field_proto,
+                                    upb_MessageDef* m, upb_FieldDef* f) {
   _upb_FieldDef_Create(ctx, prefix, field_proto, m, f);
   f->is_extension_ = true;
 
-  if (google_protobuf_FieldDescriptorProto_has_oneof_index(field_proto)) {
+  if (UPB_DESC(FieldDescriptorProto_has_oneof_index)(field_proto)) {
     _upb_DefBuilder_Errf(ctx, "oneof_index provided for extension field (%s)",
                          f->full_name);
   }
@@ -685,14 +687,14 @@ static void _upb_FieldDef_CreateExt(
   }
 }
 
-static void _upb_FieldDef_CreateNotExt(
-    upb_DefBuilder* ctx, const char* prefix,
-    const google_protobuf_FieldDescriptorProto* field_proto, upb_MessageDef* m,
-    upb_FieldDef* f) {
+static void _upb_FieldDef_CreateNotExt(upb_DefBuilder* ctx, const char* prefix,
+                                       const UPB_DESC(FieldDescriptorProto) *
+                                           field_proto,
+                                       upb_MessageDef* m, upb_FieldDef* f) {
   _upb_FieldDef_Create(ctx, prefix, field_proto, m, f);
   f->is_extension_ = false;
 
-  if (!google_protobuf_FieldDescriptorProto_has_oneof_index(field_proto)) {
+  if (!UPB_DESC(FieldDescriptorProto_has_oneof_index)(field_proto)) {
     if (f->proto3_optional_) {
       _upb_DefBuilder_Errf(
           ctx,
@@ -719,7 +721,7 @@ static void _upb_FieldDef_CreateNotExt(
 
 upb_FieldDef* _upb_FieldDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_FieldDescriptorProto* const* protos, const char* prefix,
+    const UPB_DESC(FieldDescriptorProto) * const* protos, const char* prefix,
     upb_MessageDef* m, bool* is_sorted) {
   _upb_DefType_CheckPadding(sizeof(upb_FieldDef));
   upb_FieldDef* defs =
@@ -754,11 +756,9 @@ upb_FieldDef* _upb_FieldDefs_New(
 
 static void resolve_subdef(upb_DefBuilder* ctx, const char* prefix,
                            upb_FieldDef* f) {
-  const google_protobuf_FieldDescriptorProto* field_proto = f->sub.unresolved;
-  upb_StringView name =
-      google_protobuf_FieldDescriptorProto_type_name(field_proto);
-  bool has_name =
-      google_protobuf_FieldDescriptorProto_has_type_name(field_proto);
+  const UPB_DESC(FieldDescriptorProto)* field_proto = f->sub.unresolved;
+  upb_StringView name = UPB_DESC(FieldDescriptorProto_type_name)(field_proto);
+  bool has_name = UPB_DESC(FieldDescriptorProto_has_type_name)(field_proto);
   switch ((int)f->type_) {
     case UPB_FIELD_TYPE_UNSPECIFIED: {
       // Type was not specified and must be inferred.
@@ -843,13 +843,14 @@ bool upb_FieldDef_MiniDescriptorEncode(const upb_FieldDef* f, upb_Arena* a,
 
 static void resolve_extension(upb_DefBuilder* ctx, const char* prefix,
                               upb_FieldDef* f,
-                              const google_protobuf_FieldDescriptorProto* field_proto) {
-  if (!google_protobuf_FieldDescriptorProto_has_extendee(field_proto)) {
+                              const UPB_DESC(FieldDescriptorProto) *
+                                  field_proto) {
+  if (!UPB_DESC(FieldDescriptorProto_has_extendee)(field_proto)) {
     _upb_DefBuilder_Errf(ctx, "extension for field '%s' had no extendee",
                          f->full_name);
   }
 
-  upb_StringView name = google_protobuf_FieldDescriptorProto_extendee(field_proto);
+  upb_StringView name = UPB_DESC(FieldDescriptorProto_extendee)(field_proto);
   const upb_MessageDef* m =
       _upb_DefBuilder_Resolve(ctx, f->full_name, prefix, name, UPB_DEFTYPE_MSG);
   f->msgdef = m;
@@ -889,12 +890,13 @@ static void resolve_extension(upb_DefBuilder* ctx, const char* prefix,
 }
 
 static void resolve_default(upb_DefBuilder* ctx, upb_FieldDef* f,
-                            const google_protobuf_FieldDescriptorProto* field_proto) {
+                            const UPB_DESC(FieldDescriptorProto) *
+                                field_proto) {
   // Have to delay resolving of the default value until now because of the enum
   // case, since enum defaults are specified with a label.
-  if (google_protobuf_FieldDescriptorProto_has_default_value(field_proto)) {
+  if (UPB_DESC(FieldDescriptorProto_has_default_value)(field_proto)) {
     upb_StringView defaultval =
-        google_protobuf_FieldDescriptorProto_default_value(field_proto);
+        UPB_DESC(FieldDescriptorProto_default_value)(field_proto);
 
     if (upb_FileDef_Syntax(f->file) == kUpb_Syntax_Proto3) {
       _upb_DefBuilder_Errf(ctx,
@@ -919,7 +921,7 @@ static void resolve_default(upb_DefBuilder* ctx, upb_FieldDef* f,
 void _upb_FieldDef_Resolve(upb_DefBuilder* ctx, const char* prefix,
                            upb_FieldDef* f) {
   // We have to stash this away since resolve_subdef() may overwrite it.
-  const google_protobuf_FieldDescriptorProto* field_proto = f->sub.unresolved;
+  const UPB_DESC(FieldDescriptorProto)* field_proto = f->sub.unresolved;
 
   resolve_subdef(ctx, prefix, f);
   resolve_default(ctx, f, field_proto);
diff --git a/upb/reflection/field_def.h b/upb/reflection/field_def.h
index 6e4f5a24bf..4502162f32 100644
--- a/upb/reflection/field_def.h
+++ b/upb/reflection/field_def.h
@@ -78,7 +78,7 @@ bool upb_FieldDef_MiniDescriptorEncode(const upb_FieldDef* f, upb_Arena* a,
 const upb_MiniTableField* upb_FieldDef_MiniTable(const upb_FieldDef* f);
 const char* upb_FieldDef_Name(const upb_FieldDef* f);
 uint32_t upb_FieldDef_Number(const upb_FieldDef* f);
-const google_protobuf_FieldOptions* upb_FieldDef_Options(const upb_FieldDef* f);
+const UPB_DESC(FieldOptions) * upb_FieldDef_Options(const upb_FieldDef* f);
 const upb_OneofDef* upb_FieldDef_RealContainingOneof(const upb_FieldDef* f);
 upb_FieldType upb_FieldDef_Type(const upb_FieldDef* f);
 
diff --git a/upb/reflection/field_def_internal.h b/upb/reflection/field_def_internal.h
index e2040aaab8..14ad9b69fd 100644
--- a/upb/reflection/field_def_internal.h
+++ b/upb/reflection/field_def_internal.h
@@ -51,7 +51,7 @@ void _upb_FieldDef_Resolve(upb_DefBuilder* ctx, const char* prefix,
 // Allocate and initialize an array of |n| field defs.
 upb_FieldDef* _upb_FieldDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_FieldDescriptorProto* const* protos, const char* prefix,
+    const UPB_DESC(FieldDescriptorProto) * const* protos, const char* prefix,
     upb_MessageDef* m, bool* is_sorted);
 
 // Allocate and return a list of pointers to the |n| field defs in |ff|,
diff --git a/upb/reflection/file_def.c b/upb/reflection/file_def.c
index 91da5dfb92..cffee1cf94 100644
--- a/upb/reflection/file_def.c
+++ b/upb/reflection/file_def.c
@@ -37,7 +37,7 @@
 #include "upb/port/def.inc"
 
 struct upb_FileDef {
-  const google_protobuf_FileOptions* opts;
+  const UPB_DESC(FileOptions) * opts;
   const char* name;
   const char* package;
 
@@ -62,7 +62,7 @@ struct upb_FileDef {
   upb_Syntax syntax;
 };
 
-const google_protobuf_FileOptions* upb_FileDef_Options(const upb_FileDef* f) {
+const UPB_DESC(FileOptions) * upb_FileDef_Options(const upb_FileDef* f) {
   return f->opts;
 }
 
@@ -164,13 +164,13 @@ static bool streql_view(upb_StringView view, const char* b) {
   return view.size == strlen(b) && memcmp(view.data, b, view.size) == 0;
 }
 
-static int count_exts_in_msg(const google_protobuf_DescriptorProto* msg_proto) {
+static int count_exts_in_msg(const UPB_DESC(DescriptorProto) * msg_proto) {
   size_t n;
-  google_protobuf_DescriptorProto_extension(msg_proto, &n);
+  UPB_DESC(DescriptorProto_extension)(msg_proto, &n);
   int ext_count = n;
 
-  const google_protobuf_DescriptorProto* const* nested_msgs =
-      google_protobuf_DescriptorProto_nested_type(msg_proto, &n);
+  const UPB_DESC(DescriptorProto)* const* nested_msgs =
+      UPB_DESC(DescriptorProto_nested_type)(msg_proto, &n);
   for (size_t i = 0; i < n; i++) {
     ext_count += count_exts_in_msg(nested_msgs[i]);
   }
@@ -180,14 +180,14 @@ static int count_exts_in_msg(const google_protobuf_DescriptorProto* msg_proto) {
 
 // Allocate and initialize one file def, and add it to the context object.
 void _upb_FileDef_Create(upb_DefBuilder* ctx,
-                         const google_protobuf_FileDescriptorProto* file_proto) {
+                         const UPB_DESC(FileDescriptorProto) * file_proto) {
   upb_FileDef* file = _upb_DefBuilder_Alloc(ctx, sizeof(upb_FileDef));
   ctx->file = file;
 
-  const google_protobuf_DescriptorProto* const* msgs;
-  const google_protobuf_EnumDescriptorProto* const* enums;
-  const google_protobuf_FieldDescriptorProto* const* exts;
-  const google_protobuf_ServiceDescriptorProto* const* services;
+  const UPB_DESC(DescriptorProto)* const* msgs;
+  const UPB_DESC(EnumDescriptorProto)* const* enums;
+  const UPB_DESC(FieldDescriptorProto)* const* exts;
+  const UPB_DESC(ServiceDescriptorProto)* const* services;
   const upb_StringView* strs;
   const int32_t* public_deps;
   const int32_t* weak_deps;
@@ -196,9 +196,9 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
   file->symtab = ctx->symtab;
 
   // Count all extensions in the file, to build a flat array of layouts.
-  google_protobuf_FileDescriptorProto_extension(file_proto, &n);
+  UPB_DESC(FileDescriptorProto_extension)(file_proto, &n);
   int ext_count = n;
-  msgs = google_protobuf_FileDescriptorProto_message_type(file_proto, &n);
+  msgs = UPB_DESC(FileDescriptorProto_message_type)(file_proto, &n);
   for (int i = 0; i < n; i++) {
     ext_count += count_exts_in_msg(msgs[i]);
   }
@@ -223,13 +223,13 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
     }
   }
 
-  if (!google_protobuf_FileDescriptorProto_has_name(file_proto)) {
+  if (!UPB_DESC(FileDescriptorProto_has_name)(file_proto)) {
     _upb_DefBuilder_Errf(ctx, "File has no name");
   }
 
-  file->name = strviewdup(ctx, google_protobuf_FileDescriptorProto_name(file_proto));
+  file->name = strviewdup(ctx, UPB_DESC(FileDescriptorProto_name)(file_proto));
 
-  upb_StringView package = google_protobuf_FileDescriptorProto_package(file_proto);
+  upb_StringView package = UPB_DESC(FileDescriptorProto_package)(file_proto);
   if (package.size) {
     _upb_DefBuilder_CheckIdentFull(ctx, package);
     file->package = strviewdup(ctx, package);
@@ -237,8 +237,8 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
     file->package = NULL;
   }
 
-  if (google_protobuf_FileDescriptorProto_has_syntax(file_proto)) {
-    upb_StringView syntax = google_protobuf_FileDescriptorProto_syntax(file_proto);
+  if (UPB_DESC(FileDescriptorProto_has_syntax)(file_proto)) {
+    upb_StringView syntax = UPB_DESC(FileDescriptorProto_syntax)(file_proto);
 
     if (streql_view(syntax, "proto2")) {
       file->syntax = kUpb_Syntax_Proto2;
@@ -256,7 +256,7 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
   UPB_DEF_SET_OPTIONS(file->opts, FileDescriptorProto, FileOptions, file_proto);
 
   // Verify dependencies.
-  strs = google_protobuf_FileDescriptorProto_dependency(file_proto, &n);
+  strs = UPB_DESC(FileDescriptorProto_dependency)(file_proto, &n);
   file->dep_count = n;
   file->deps = _upb_DefBuilder_Alloc(ctx, sizeof(*file->deps) * n);
 
@@ -272,7 +272,7 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
     }
   }
 
-  public_deps = google_protobuf_FileDescriptorProto_public_dependency(file_proto, &n);
+  public_deps = UPB_DESC(FileDescriptorProto_public_dependency)(file_proto, &n);
   file->public_dep_count = n;
   file->public_deps =
       _upb_DefBuilder_Alloc(ctx, sizeof(*file->public_deps) * n);
@@ -285,7 +285,7 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
     mutable_public_deps[i] = public_deps[i];
   }
 
-  weak_deps = google_protobuf_FileDescriptorProto_weak_dependency(file_proto, &n);
+  weak_deps = UPB_DESC(FileDescriptorProto_weak_dependency)(file_proto, &n);
   file->weak_dep_count = n;
   file->weak_deps = _upb_DefBuilder_Alloc(ctx, sizeof(*file->weak_deps) * n);
   int32_t* mutable_weak_deps = (int32_t*)file->weak_deps;
@@ -298,23 +298,23 @@ void _upb_FileDef_Create(upb_DefBuilder* ctx,
   }
 
   // Create enums.
-  enums = google_protobuf_FileDescriptorProto_enum_type(file_proto, &n);
+  enums = UPB_DESC(FileDescriptorProto_enum_type)(file_proto, &n);
   file->top_lvl_enum_count = n;
   file->top_lvl_enums = _upb_EnumDefs_New(ctx, n, enums, NULL);
 
   // Create extensions.
-  exts = google_protobuf_FileDescriptorProto_extension(file_proto, &n);
+  exts = UPB_DESC(FileDescriptorProto_extension)(file_proto, &n);
   file->top_lvl_ext_count = n;
   file->top_lvl_exts =
       _upb_FieldDefs_New(ctx, n, exts, file->package, NULL, NULL);
 
   // Create messages.
-  msgs = google_protobuf_FileDescriptorProto_message_type(file_proto, &n);
+  msgs = UPB_DESC(FileDescriptorProto_message_type)(file_proto, &n);
   file->top_lvl_msg_count = n;
   file->top_lvl_msgs = _upb_MessageDefs_New(ctx, n, msgs, NULL);
 
   // Create services.
-  services = google_protobuf_FileDescriptorProto_service(file_proto, &n);
+  services = UPB_DESC(FileDescriptorProto_service)(file_proto, &n);
   file->service_count = n;
   file->services = _upb_ServiceDefs_New(ctx, n, services);
 
diff --git a/upb/reflection/file_def.h b/upb/reflection/file_def.h
index ebaa960f50..3d2abc69cf 100644
--- a/upb/reflection/file_def.h
+++ b/upb/reflection/file_def.h
@@ -43,7 +43,7 @@ const upb_FileDef* upb_FileDef_Dependency(const upb_FileDef* f, int i);
 int upb_FileDef_DependencyCount(const upb_FileDef* f);
 bool upb_FileDef_HasOptions(const upb_FileDef* f);
 const char* upb_FileDef_Name(const upb_FileDef* f);
-const google_protobuf_FileOptions* upb_FileDef_Options(const upb_FileDef* f);
+const UPB_DESC(FileOptions) * upb_FileDef_Options(const upb_FileDef* f);
 const char* upb_FileDef_Package(const upb_FileDef* f);
 const upb_DefPool* upb_FileDef_Pool(const upb_FileDef* f);
 
diff --git a/upb/reflection/file_def_internal.h b/upb/reflection/file_def_internal.h
index f58a18b1c9..1d29bb6fab 100644
--- a/upb/reflection/file_def_internal.h
+++ b/upb/reflection/file_def_internal.h
@@ -46,7 +46,7 @@ const int32_t* _upb_FileDef_WeakDependencyIndexes(const upb_FileDef* f);
 const char* _upb_FileDef_RawPackage(const upb_FileDef* f);
 
 void _upb_FileDef_Create(upb_DefBuilder* ctx,
-                         const google_protobuf_FileDescriptorProto* file_proto);
+                         const UPB_DESC(FileDescriptorProto) * file_proto);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/message_def.c b/upb/reflection/message_def.c
index e947a7b7d6..a2b71c1852 100644
--- a/upb/reflection/message_def.c
+++ b/upb/reflection/message_def.c
@@ -44,7 +44,7 @@
 #include "upb/port/def.inc"
 
 struct upb_MessageDef {
-  const google_protobuf_MessageOptions* opts;
+  const UPB_DESC(MessageOptions) * opts;
   const upb_MiniTable* layout;
   const upb_FileDef* file;
   const upb_MessageDef* containing_type;
@@ -141,7 +141,8 @@ bool _upb_MessageDef_IsValidExtensionNumber(const upb_MessageDef* m, int n) {
   return false;
 }
 
-const google_protobuf_MessageOptions* upb_MessageDef_Options(const upb_MessageDef* m) {
+const UPB_DESC(MessageOptions) *
+    upb_MessageDef_Options(const upb_MessageDef* m) {
   return m->opts;
 }
 
@@ -255,6 +256,10 @@ int upb_MessageDef_OneofCount(const upb_MessageDef* m) {
   return m->oneof_count;
 }
 
+int upb_MessageDef_RealOneofCount(const upb_MessageDef* m) {
+  return m->real_oneof_count;
+}
+
 int upb_MessageDef_NestedMessageCount(const upb_MessageDef* m) {
   return m->nested_msg_count;
 }
@@ -334,11 +339,11 @@ const upb_OneofDef* upb_MessageDef_FindOneofByName(const upb_MessageDef* m,
 }
 
 bool upb_MessageDef_IsMapEntry(const upb_MessageDef* m) {
-  return google_protobuf_MessageOptions_map_entry(m->opts);
+  return UPB_DESC(MessageOptions_map_entry)(m->opts);
 }
 
 bool upb_MessageDef_IsMessageSet(const upb_MessageDef* m) {
-  return google_protobuf_MessageOptions_message_set_wire_format(m->opts);
+  return UPB_DESC(MessageOptions_message_set_wire_format)(m->opts);
 }
 
 static upb_MiniTable* _upb_MessageDef_MakeMiniTable(upb_DefBuilder* ctx,
@@ -387,7 +392,7 @@ void _upb_MessageDef_Resolve(upb_DefBuilder* ctx, upb_MessageDef* m) {
     if (upb_FieldDef_Type(ext) == kUpb_FieldType_Message &&
         upb_FieldDef_Label(ext) == kUpb_Label_Optional &&
         upb_FieldDef_MessageSubDef(ext) == m &&
-        google_protobuf_MessageOptions_message_set_wire_format(
+        UPB_DESC(MessageOptions_message_set_wire_format)(
             upb_MessageDef_Options(upb_FieldDef_ContainingType(ext)))) {
       m->in_message_set = true;
     }
@@ -556,7 +561,7 @@ bool upb_MessageDef_MiniDescriptorEncode(const upb_MessageDef* m, upb_Arena* a,
 
   if (upb_MessageDef_IsMapEntry(m)) {
     if (!_upb_MessageDef_EncodeMap(&s, m, a)) return false;
-  } else if (google_protobuf_MessageOptions_message_set_wire_format(m->opts)) {
+  } else if (UPB_DESC(MessageOptions_message_set_wire_format)(m->opts)) {
     if (!_upb_MessageDef_EncodeMessageSet(&s, m, a)) return false;
   } else {
     if (!_upb_MessageDef_EncodeMessage(&s, m, a)) return false;
@@ -582,13 +587,13 @@ static upb_StringView* _upb_ReservedNames_New(upb_DefBuilder* ctx, int n,
 }
 
 static void create_msgdef(upb_DefBuilder* ctx, const char* prefix,
-                          const google_protobuf_DescriptorProto* msg_proto,
+                          const UPB_DESC(DescriptorProto) * msg_proto,
                           const upb_MessageDef* containing_type,
                           upb_MessageDef* m) {
-  const google_protobuf_OneofDescriptorProto* const* oneofs;
-  const google_protobuf_FieldDescriptorProto* const* fields;
-  const google_protobuf_DescriptorProto_ExtensionRange* const* ext_ranges;
-  const google_protobuf_DescriptorProto_ReservedRange* const* res_ranges;
+  const UPB_DESC(OneofDescriptorProto)* const* oneofs;
+  const UPB_DESC(FieldDescriptorProto)* const* fields;
+  const UPB_DESC(DescriptorProto_ExtensionRange)* const* ext_ranges;
+  const UPB_DESC(DescriptorProto_ReservedRange)* const* res_ranges;
   const upb_StringView* res_names;
   size_t n_oneof, n_field, n_enum, n_ext, n_msg;
   size_t n_ext_range, n_res_range, n_res_name;
@@ -600,17 +605,19 @@ static void create_msgdef(upb_DefBuilder* ctx, const char* prefix,
   m->containing_type = containing_type;
   m->is_sorted = true;
 
-  name = google_protobuf_DescriptorProto_name(msg_proto);
+  name = UPB_DESC(DescriptorProto_name)(msg_proto);
   _upb_DefBuilder_CheckIdentNotFull(ctx, name);
 
   m->full_name = _upb_DefBuilder_MakeFullName(ctx, prefix, name);
   _upb_DefBuilder_Add(ctx, m->full_name, _upb_DefType_Pack(m, UPB_DEFTYPE_MSG));
 
-  oneofs = google_protobuf_DescriptorProto_oneof_decl(msg_proto, &n_oneof);
-  fields = google_protobuf_DescriptorProto_field(msg_proto, &n_field);
-  ext_ranges = google_protobuf_DescriptorProto_extension_range(msg_proto, &n_ext_range);
-  res_ranges = google_protobuf_DescriptorProto_reserved_range(msg_proto, &n_res_range);
-  res_names = google_protobuf_DescriptorProto_reserved_name(msg_proto, &n_res_name);
+  oneofs = UPB_DESC(DescriptorProto_oneof_decl)(msg_proto, &n_oneof);
+  fields = UPB_DESC(DescriptorProto_field)(msg_proto, &n_field);
+  ext_ranges =
+      UPB_DESC(DescriptorProto_extension_range)(msg_proto, &n_ext_range);
+  res_ranges =
+      UPB_DESC(DescriptorProto_reserved_range)(msg_proto, &n_res_range);
+  res_names = UPB_DESC(DescriptorProto_reserved_name)(msg_proto, &n_res_name);
 
   bool ok = upb_inttable_init(&m->itof, ctx->arena);
   if (!ok) _upb_DefBuilder_OomErr(ctx);
@@ -639,7 +646,7 @@ static void create_msgdef(upb_DefBuilder* ctx, const char* prefix,
       _upb_FieldDefs_New(ctx, n_field, fields, m->full_name, m, &m->is_sorted);
 
   // Message Sets may not contain fields.
-  if (UPB_UNLIKELY(google_protobuf_MessageOptions_message_set_wire_format(m->opts))) {
+  if (UPB_UNLIKELY(UPB_DESC(MessageOptions_message_set_wire_format)(m->opts))) {
     if (UPB_UNLIKELY(n_field > 0)) {
       _upb_DefBuilder_Errf(ctx, "invalid message set (%s)", m->full_name);
     }
@@ -661,25 +668,25 @@ static void create_msgdef(upb_DefBuilder* ctx, const char* prefix,
   assign_msg_wellknowntype(m);
   upb_inttable_compact(&m->itof, ctx->arena);
 
-  const google_protobuf_EnumDescriptorProto* const* enums =
-      google_protobuf_DescriptorProto_enum_type(msg_proto, &n_enum);
+  const UPB_DESC(EnumDescriptorProto)* const* enums =
+      UPB_DESC(DescriptorProto_enum_type)(msg_proto, &n_enum);
   m->nested_enum_count = n_enum;
   m->nested_enums = _upb_EnumDefs_New(ctx, n_enum, enums, m);
 
-  const google_protobuf_FieldDescriptorProto* const* exts =
-      google_protobuf_DescriptorProto_extension(msg_proto, &n_ext);
+  const UPB_DESC(FieldDescriptorProto)* const* exts =
+      UPB_DESC(DescriptorProto_extension)(msg_proto, &n_ext);
   m->nested_ext_count = n_ext;
   m->nested_exts = _upb_FieldDefs_New(ctx, n_ext, exts, m->full_name, m, NULL);
 
-  const google_protobuf_DescriptorProto* const* msgs =
-      google_protobuf_DescriptorProto_nested_type(msg_proto, &n_msg);
+  const UPB_DESC(DescriptorProto)* const* msgs =
+      UPB_DESC(DescriptorProto_nested_type)(msg_proto, &n_msg);
   m->nested_msg_count = n_msg;
   m->nested_msgs = _upb_MessageDefs_New(ctx, n_msg, msgs, m);
 }
 
 // Allocate and initialize an array of |n| message defs.
 upb_MessageDef* _upb_MessageDefs_New(
-    upb_DefBuilder* ctx, int n, const google_protobuf_DescriptorProto* const* protos,
+    upb_DefBuilder* ctx, int n, const UPB_DESC(DescriptorProto) * const* protos,
     const upb_MessageDef* containing_type) {
   _upb_DefType_CheckPadding(sizeof(upb_MessageDef));
 
diff --git a/upb/reflection/message_def.h b/upb/reflection/message_def.h
index d47bf3386a..d1d9891c01 100644
--- a/upb/reflection/message_def.h
+++ b/upb/reflection/message_def.h
@@ -150,8 +150,10 @@ int upb_MessageDef_NestedMessageCount(const upb_MessageDef* m);
 
 const upb_OneofDef* upb_MessageDef_Oneof(const upb_MessageDef* m, int i);
 int upb_MessageDef_OneofCount(const upb_MessageDef* m);
+int upb_MessageDef_RealOneofCount(const upb_MessageDef* m);
 
-const google_protobuf_MessageOptions* upb_MessageDef_Options(const upb_MessageDef* m);
+const UPB_DESC(MessageOptions) *
+    upb_MessageDef_Options(const upb_MessageDef* m);
 
 upb_StringView upb_MessageDef_ReservedName(const upb_MessageDef* m, int i);
 int upb_MessageDef_ReservedNameCount(const upb_MessageDef* m);
diff --git a/upb/reflection/message_def_internal.h b/upb/reflection/message_def_internal.h
index ba96cc22b7..d83663a3eb 100644
--- a/upb/reflection/message_def_internal.h
+++ b/upb/reflection/message_def_internal.h
@@ -50,7 +50,7 @@ void _upb_MessageDef_Resolve(upb_DefBuilder* ctx, upb_MessageDef* m);
 
 // Allocate and initialize an array of |n| message defs.
 upb_MessageDef* _upb_MessageDefs_New(
-    upb_DefBuilder* ctx, int n, const google_protobuf_DescriptorProto* const* protos,
+    upb_DefBuilder* ctx, int n, const UPB_DESC(DescriptorProto) * const* protos,
     const upb_MessageDef* containing_type);
 
 #ifdef __cplusplus
diff --git a/upb/reflection/message_reserved_range.c b/upb/reflection/message_reserved_range.c
index caf80dbc87..5b6bf00664 100644
--- a/upb/reflection/message_reserved_range.c
+++ b/upb/reflection/message_reserved_range.c
@@ -53,14 +53,15 @@ int32_t upb_MessageReservedRange_End(const upb_MessageReservedRange* r) {
 
 upb_MessageReservedRange* _upb_MessageReservedRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_DescriptorProto_ReservedRange* const* protos,
+    const UPB_DESC(DescriptorProto_ReservedRange) * const* protos,
     const upb_MessageDef* m) {
   upb_MessageReservedRange* r =
       _upb_DefBuilder_Alloc(ctx, sizeof(upb_MessageReservedRange) * n);
 
   for (int i = 0; i < n; i++) {
-    const int32_t start = google_protobuf_DescriptorProto_ReservedRange_start(protos[i]);
-    const int32_t end = google_protobuf_DescriptorProto_ReservedRange_end(protos[i]);
+    const int32_t start =
+        UPB_DESC(DescriptorProto_ReservedRange_start)(protos[i]);
+    const int32_t end = UPB_DESC(DescriptorProto_ReservedRange_end)(protos[i]);
     const int32_t max = kUpb_MaxFieldNumber + 1;
 
     // A full validation would also check that each range is disjoint, and that
diff --git a/upb/reflection/message_reserved_range_internal.h b/upb/reflection/message_reserved_range_internal.h
index 03e8a8ad76..37b10be24c 100644
--- a/upb/reflection/message_reserved_range_internal.h
+++ b/upb/reflection/message_reserved_range_internal.h
@@ -43,7 +43,7 @@ upb_MessageReservedRange* _upb_MessageReservedRange_At(
 // Allocate and initialize an array of |n| reserved ranges owned by |m|.
 upb_MessageReservedRange* _upb_MessageReservedRanges_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_DescriptorProto_ReservedRange* const* protos,
+    const UPB_DESC(DescriptorProto_ReservedRange) * const* protos,
     const upb_MessageDef* m);
 
 #ifdef __cplusplus
diff --git a/upb/reflection/method_def.c b/upb/reflection/method_def.c
index 9a4971d5c2..7c4fd30d41 100644
--- a/upb/reflection/method_def.c
+++ b/upb/reflection/method_def.c
@@ -34,7 +34,7 @@
 #include "upb/port/def.inc"
 
 struct upb_MethodDef {
-  const google_protobuf_MethodOptions* opts;
+  const UPB_DESC(MethodOptions) * opts;
   upb_ServiceDef* service;
   const char* full_name;
   const upb_MessageDef* input_type;
@@ -52,7 +52,7 @@ const upb_ServiceDef* upb_MethodDef_Service(const upb_MethodDef* m) {
   return m->service;
 }
 
-const google_protobuf_MethodOptions* upb_MethodDef_Options(const upb_MethodDef* m) {
+const UPB_DESC(MethodOptions) * upb_MethodDef_Options(const upb_MethodDef* m) {
   return m->opts;
 }
 
@@ -87,23 +87,25 @@ bool upb_MethodDef_ServerStreaming(const upb_MethodDef* m) {
 }
 
 static void create_method(upb_DefBuilder* ctx,
-                          const google_protobuf_MethodDescriptorProto* method_proto,
+                          const UPB_DESC(MethodDescriptorProto) * method_proto,
                           upb_ServiceDef* s, upb_MethodDef* m) {
-  upb_StringView name = google_protobuf_MethodDescriptorProto_name(method_proto);
+  upb_StringView name = UPB_DESC(MethodDescriptorProto_name)(method_proto);
 
   m->service = s;
   m->full_name =
       _upb_DefBuilder_MakeFullName(ctx, upb_ServiceDef_FullName(s), name);
   m->client_streaming =
-      google_protobuf_MethodDescriptorProto_client_streaming(method_proto);
+      UPB_DESC(MethodDescriptorProto_client_streaming)(method_proto);
   m->server_streaming =
-      google_protobuf_MethodDescriptorProto_server_streaming(method_proto);
+      UPB_DESC(MethodDescriptorProto_server_streaming)(method_proto);
   m->input_type = _upb_DefBuilder_Resolve(
       ctx, m->full_name, m->full_name,
-      google_protobuf_MethodDescriptorProto_input_type(method_proto), UPB_DEFTYPE_MSG);
+      UPB_DESC(MethodDescriptorProto_input_type)(method_proto),
+      UPB_DEFTYPE_MSG);
   m->output_type = _upb_DefBuilder_Resolve(
       ctx, m->full_name, m->full_name,
-      google_protobuf_MethodDescriptorProto_output_type(method_proto), UPB_DEFTYPE_MSG);
+      UPB_DESC(MethodDescriptorProto_output_type)(method_proto),
+      UPB_DEFTYPE_MSG);
 
   UPB_DEF_SET_OPTIONS(m->opts, MethodDescriptorProto, MethodOptions,
                       method_proto);
@@ -112,7 +114,7 @@ static void create_method(upb_DefBuilder* ctx,
 // Allocate and initialize an array of |n| method defs belonging to |s|.
 upb_MethodDef* _upb_MethodDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_MethodDescriptorProto* const* protos, upb_ServiceDef* s) {
+    const UPB_DESC(MethodDescriptorProto) * const* protos, upb_ServiceDef* s) {
   upb_MethodDef* m = _upb_DefBuilder_Alloc(ctx, sizeof(upb_MethodDef) * n);
   for (int i = 0; i < n; i++) {
     create_method(ctx, protos[i], s, &m[i]);
diff --git a/upb/reflection/method_def.h b/upb/reflection/method_def.h
index 3460886b1e..fdf0534db0 100644
--- a/upb/reflection/method_def.h
+++ b/upb/reflection/method_def.h
@@ -45,7 +45,7 @@ bool upb_MethodDef_HasOptions(const upb_MethodDef* m);
 int upb_MethodDef_Index(const upb_MethodDef* m);
 const upb_MessageDef* upb_MethodDef_InputType(const upb_MethodDef* m);
 const char* upb_MethodDef_Name(const upb_MethodDef* m);
-const google_protobuf_MethodOptions* upb_MethodDef_Options(const upb_MethodDef* m);
+const UPB_DESC(MethodOptions) * upb_MethodDef_Options(const upb_MethodDef* m);
 const upb_MessageDef* upb_MethodDef_OutputType(const upb_MethodDef* m);
 bool upb_MethodDef_ServerStreaming(const upb_MethodDef* m);
 const upb_ServiceDef* upb_MethodDef_Service(const upb_MethodDef* m);
diff --git a/upb/reflection/method_def_internal.h b/upb/reflection/method_def_internal.h
index 1eeff262ea..c6629ff9f2 100644
--- a/upb/reflection/method_def_internal.h
+++ b/upb/reflection/method_def_internal.h
@@ -42,7 +42,7 @@ upb_MethodDef* _upb_MethodDef_At(const upb_MethodDef* m, int i);
 // Allocate and initialize an array of |n| method defs owned by |s|.
 upb_MethodDef* _upb_MethodDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_MethodDescriptorProto* const* protos, upb_ServiceDef* s);
+    const UPB_DESC(MethodDescriptorProto) * const* protos, upb_ServiceDef* s);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/oneof_def.c b/upb/reflection/oneof_def.c
index 869ffd1115..767bdc49cf 100644
--- a/upb/reflection/oneof_def.c
+++ b/upb/reflection/oneof_def.c
@@ -41,7 +41,7 @@
 #include "upb/port/def.inc"
 
 struct upb_OneofDef {
-  const google_protobuf_OneofOptions* opts;
+  const UPB_DESC(OneofOptions) * opts;
   const upb_MessageDef* parent;
   const char* full_name;
   int field_count;
@@ -58,7 +58,7 @@ upb_OneofDef* _upb_OneofDef_At(const upb_OneofDef* o, int i) {
   return (upb_OneofDef*)&o[i];
 }
 
-const google_protobuf_OneofOptions* upb_OneofDef_Options(const upb_OneofDef* o) {
+const UPB_DESC(OneofOptions) * upb_OneofDef_Options(const upb_OneofDef* o) {
   return o->opts;
 }
 
@@ -164,10 +164,10 @@ size_t _upb_OneofDefs_Finalize(upb_DefBuilder* ctx, upb_MessageDef* m) {
 }
 
 static void create_oneofdef(upb_DefBuilder* ctx, upb_MessageDef* m,
-                            const google_protobuf_OneofDescriptorProto* oneof_proto,
+                            const UPB_DESC(OneofDescriptorProto) * oneof_proto,
                             const upb_OneofDef* _o) {
   upb_OneofDef* o = (upb_OneofDef*)_o;
-  upb_StringView name = google_protobuf_OneofDescriptorProto_name(oneof_proto);
+  upb_StringView name = UPB_DESC(OneofDescriptorProto_name)(oneof_proto);
 
   o->parent = m;
   o->full_name =
@@ -195,7 +195,7 @@ static void create_oneofdef(upb_DefBuilder* ctx, upb_MessageDef* m,
 // Allocate and initialize an array of |n| oneof defs.
 upb_OneofDef* _upb_OneofDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_OneofDescriptorProto* const* protos, upb_MessageDef* m) {
+    const UPB_DESC(OneofDescriptorProto) * const* protos, upb_MessageDef* m) {
   _upb_DefType_CheckPadding(sizeof(upb_OneofDef));
 
   upb_OneofDef* o = _upb_DefBuilder_Alloc(ctx, sizeof(upb_OneofDef) * n);
diff --git a/upb/reflection/oneof_def.h b/upb/reflection/oneof_def.h
index bd68273214..691b40e0fa 100644
--- a/upb/reflection/oneof_def.h
+++ b/upb/reflection/oneof_def.h
@@ -55,7 +55,7 @@ const upb_FieldDef* upb_OneofDef_LookupNumber(const upb_OneofDef* o,
                                               uint32_t num);
 const char* upb_OneofDef_Name(const upb_OneofDef* o);
 int upb_OneofDef_numfields(const upb_OneofDef* o);
-const google_protobuf_OneofOptions* upb_OneofDef_Options(const upb_OneofDef* o);
+const UPB_DESC(OneofOptions) * upb_OneofDef_Options(const upb_OneofDef* o);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/oneof_def_internal.h b/upb/reflection/oneof_def_internal.h
index 807b558676..3a98c6739c 100644
--- a/upb/reflection/oneof_def_internal.h
+++ b/upb/reflection/oneof_def_internal.h
@@ -44,7 +44,7 @@ bool _upb_OneofDef_Insert(upb_OneofDef* o, const upb_FieldDef* f,
 // Allocate and initialize an array of |n| oneof defs owned by |m|.
 upb_OneofDef* _upb_OneofDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_OneofDescriptorProto* const* protos, upb_MessageDef* m);
+    const UPB_DESC(OneofDescriptorProto) * const* protos, upb_MessageDef* m);
 
 size_t _upb_OneofDefs_Finalize(upb_DefBuilder* ctx, upb_MessageDef* m);
 
diff --git a/upb/reflection/service_def.c b/upb/reflection/service_def.c
index b904aff61a..cdd3a889ef 100644
--- a/upb/reflection/service_def.c
+++ b/upb/reflection/service_def.c
@@ -35,7 +35,7 @@
 #include "upb/port/def.inc"
 
 struct upb_ServiceDef {
-  const google_protobuf_ServiceOptions* opts;
+  const UPB_DESC(ServiceOptions) * opts;
   const upb_FileDef* file;
   const char* full_name;
   upb_MethodDef* methods;
@@ -47,7 +47,8 @@ upb_ServiceDef* _upb_ServiceDef_At(const upb_ServiceDef* s, int index) {
   return (upb_ServiceDef*)&s[index];
 }
 
-const google_protobuf_ServiceOptions* upb_ServiceDef_Options(const upb_ServiceDef* s) {
+const UPB_DESC(ServiceOptions) *
+    upb_ServiceDef_Options(const upb_ServiceDef* s) {
   return s->opts;
 }
 
@@ -90,7 +91,7 @@ const upb_MethodDef* upb_ServiceDef_FindMethodByName(const upb_ServiceDef* s,
 }
 
 static void create_service(upb_DefBuilder* ctx,
-                           const google_protobuf_ServiceDescriptorProto* svc_proto,
+                           const UPB_DESC(ServiceDescriptorProto) * svc_proto,
                            upb_ServiceDef* s) {
   upb_StringView name;
   size_t n;
@@ -98,15 +99,15 @@ static void create_service(upb_DefBuilder* ctx,
   // Must happen before _upb_DefBuilder_Add()
   s->file = _upb_DefBuilder_File(ctx);
 
-  name = google_protobuf_ServiceDescriptorProto_name(svc_proto);
+  name = UPB_DESC(ServiceDescriptorProto_name)(svc_proto);
   _upb_DefBuilder_CheckIdentNotFull(ctx, name);
   const char* package = _upb_FileDef_RawPackage(s->file);
   s->full_name = _upb_DefBuilder_MakeFullName(ctx, package, name);
   _upb_DefBuilder_Add(ctx, s->full_name,
                       _upb_DefType_Pack(s, UPB_DEFTYPE_SERVICE));
 
-  const google_protobuf_MethodDescriptorProto* const* methods =
-      google_protobuf_ServiceDescriptorProto_method(svc_proto, &n);
+  const UPB_DESC(MethodDescriptorProto)* const* methods =
+      UPB_DESC(ServiceDescriptorProto_method)(svc_proto, &n);
   s->method_count = n;
   s->methods = _upb_MethodDefs_New(ctx, n, methods, s);
 
@@ -116,7 +117,7 @@ static void create_service(upb_DefBuilder* ctx,
 
 upb_ServiceDef* _upb_ServiceDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_ServiceDescriptorProto* const* protos) {
+    const UPB_DESC(ServiceDescriptorProto) * const* protos) {
   _upb_DefType_CheckPadding(sizeof(upb_ServiceDef));
 
   upb_ServiceDef* s = _upb_DefBuilder_Alloc(ctx, sizeof(upb_ServiceDef) * n);
diff --git a/upb/reflection/service_def.h b/upb/reflection/service_def.h
index 5bedd07be0..7a8f25809f 100644
--- a/upb/reflection/service_def.h
+++ b/upb/reflection/service_def.h
@@ -48,7 +48,8 @@ int upb_ServiceDef_Index(const upb_ServiceDef* s);
 const upb_MethodDef* upb_ServiceDef_Method(const upb_ServiceDef* s, int i);
 int upb_ServiceDef_MethodCount(const upb_ServiceDef* s);
 const char* upb_ServiceDef_Name(const upb_ServiceDef* s);
-const google_protobuf_ServiceOptions* upb_ServiceDef_Options(const upb_ServiceDef* s);
+const UPB_DESC(ServiceOptions) *
+    upb_ServiceDef_Options(const upb_ServiceDef* s);
 
 #ifdef __cplusplus
 } /* extern "C" */
diff --git a/upb/reflection/service_def_internal.h b/upb/reflection/service_def_internal.h
index 49201bb2f0..e79a93c190 100644
--- a/upb/reflection/service_def_internal.h
+++ b/upb/reflection/service_def_internal.h
@@ -42,7 +42,7 @@ upb_ServiceDef* _upb_ServiceDef_At(const upb_ServiceDef* s, int i);
 // Allocate and initialize an array of |n| service defs.
 upb_ServiceDef* _upb_ServiceDefs_New(
     upb_DefBuilder* ctx, int n,
-    const google_protobuf_ServiceDescriptorProto* const* protos);
+    const UPB_DESC(ServiceDescriptorProto) * const* protos);
 
 #ifdef __cplusplus
 } /* extern "C" */