diff --git a/src/google/protobuf/json/internal/untyped_message.cc b/src/google/protobuf/json/internal/untyped_message.cc
index 805d0d8310..5c3c0e86b7 100644
--- a/src/google/protobuf/json/internal/untyped_message.cc
+++ b/src/google/protobuf/json/internal/untyped_message.cc
@@ -41,9 +41,6 @@
 #include <vector>
 
 #include "google/protobuf/type.pb.h"
-#include "google/protobuf/descriptor.h"
-#include "google/protobuf/dynamic_message.h"
-#include "google/protobuf/message.h"
 #include "absl/container/flat_hash_map.h"
 #include "absl/log/absl_check.h"
 #include "absl/status/status.h"
@@ -54,8 +51,8 @@
 #include "absl/types/span.h"
 #include "absl/types/variant.h"
 #include "google/protobuf/io/coded_stream.h"
+#include "google/protobuf/port.h"
 #include "google/protobuf/util/type_resolver.h"
-#include "google/protobuf/wire_format.h"
 #include "google/protobuf/wire_format_lite.h"
 #include "utf8_validity.h"
 #include "google/protobuf/stubs/status_macros.h"
@@ -536,10 +533,16 @@ absl::Status UntypedMessage::InsertField(const ResolverPool::Field& field,
   } else if (auto* extant = absl::get_if<std::vector<T>>(&slot)) {
     extant->push_back(std::move(value));
   } else {
+    absl::optional<absl::string_view> name =
+        google::protobuf::internal::RttiTypeName<T>();
+    if (!name.has_value()) {
+      name = "<unknown>";
+    }
+
     return absl::InvalidArgumentError(
         absl::StrFormat("inconsistent types for field number %d: tried to "
-                        "insert %s, but index was %d",
-                        number, typeid(T).name(), slot.index()));
+                        "insert '%s', but index was %d",
+                        number, *name, slot.index()));
   }
 
   return absl::OkStatus();
diff --git a/src/google/protobuf/port.h b/src/google/protobuf/port.h
index 0abb04455d..9ca45d966b 100644
--- a/src/google/protobuf/port.h
+++ b/src/google/protobuf/port.h
@@ -42,8 +42,14 @@
 #include <string>
 #include <type_traits>
 
+#if PROTOBUF_RTTI
+#include <typeinfo>
+#endif
+
 
 #include "absl/meta/type_traits.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
 
 // must be last
 #include "google/protobuf/port_def.inc"
@@ -164,6 +170,16 @@ inline ToRef DownCast(From& f) {
   return *static_cast<To*>(&f);
 }
 
+// Looks up the name of `T` via RTTI, if RTTI is available.
+template <typename T>
+inline absl::optional<absl::string_view> RttiTypeName() {
+#if PROTOBUF_RTTI
+  return typeid(T).name();
+#else
+  return absl::nullopt;
+#endif
+}
+
 // Helpers for identifying our supported types.
 template <typename T>
 struct is_supported_integral_type