diff --git a/src/google/protobuf/compiler/command_line_interface.cc b/src/google/protobuf/compiler/command_line_interface.cc
index 1beca44ff2..f983646dbd 100644
--- a/src/google/protobuf/compiler/command_line_interface.cc
+++ b/src/google/protobuf/compiler/command_line_interface.cc
@@ -2937,8 +2937,8 @@ void GatherOccupiedFieldRanges(
     ranges->insert(FieldRange(fd->number(), fd->number() + 1));
   }
   for (int i = 0; i < descriptor->extension_range_count(); ++i) {
-    ranges->insert(FieldRange(descriptor->extension_range(i)->start,
-                              descriptor->extension_range(i)->end));
+    ranges->insert(FieldRange(descriptor->extension_range(i)->start_number(),
+                              descriptor->extension_range(i)->end_number()));
   }
   for (int i = 0; i < descriptor->reserved_range_count(); ++i) {
     ranges->insert(FieldRange(descriptor->reserved_range(i)->start,
diff --git a/src/google/protobuf/compiler/cpp/message.cc b/src/google/protobuf/compiler/cpp/message.cc
index 6eb8106c22..d2d9cfcd79 100644
--- a/src/google/protobuf/compiler/cpp/message.cc
+++ b/src/google/protobuf/compiler/cpp/message.cc
@@ -156,7 +156,7 @@ std::vector<const FieldDescriptor*> SortFieldsByNumber(
 struct ExtensionRangeSorter {
   bool operator()(const Descriptor::ExtensionRange* left,
                   const Descriptor::ExtensionRange* right) const {
-    return left->start < right->start;
+    return left->start_number() < right->start_number();
   }
 };
 
@@ -3672,11 +3672,11 @@ void MessageGenerator::GenerateSerializeOneField(io::Printer* p,
   format("\n");
 }
 
-void MessageGenerator::GenerateSerializeOneExtensionRange(
-    io::Printer* p, const Descriptor::ExtensionRange* range) {
+void MessageGenerator::GenerateSerializeOneExtensionRange(io::Printer* p,
+                                                          int start, int end) {
   absl::flat_hash_map<absl::string_view, std::string> vars = variables_;
-  vars["start"] = absl::StrCat(range->start);
-  vars["end"] = absl::StrCat(range->end);
+  vars["start"] = absl::StrCat(start);
+  vars["end"] = absl::StrCat(end);
   Formatter format(p, vars);
   format("// Extension range [$start$, $end$)\n");
   format(
@@ -3832,19 +3832,18 @@ void MessageGenerator::GenerateSerializeWithCachedSizesBody(io::Printer* p) {
 
     void AddToRange(const Descriptor::ExtensionRange* range) {
       if (!has_current_range_) {
-        current_combined_range_ = *range;
+        min_start_ = range->start_number();
+        max_end_ = range->end_number();
         has_current_range_ = true;
       } else {
-        current_combined_range_.start =
-            std::min(current_combined_range_.start, range->start);
-        current_combined_range_.end =
-            std::max(current_combined_range_.end, range->end);
+        min_start_ = std::min(min_start_, range->start_number());
+        max_end_ = std::max(max_end_, range->end_number());
       }
     }
 
     void Flush() {
       if (has_current_range_) {
-        mg_->GenerateSerializeOneExtensionRange(p_, &current_combined_range_);
+        mg_->GenerateSerializeOneExtensionRange(p_, min_start_, max_end_);
       }
       has_current_range_ = false;
     }
@@ -3853,7 +3852,8 @@ void MessageGenerator::GenerateSerializeWithCachedSizesBody(io::Printer* p) {
     MessageGenerator* mg_;
     io::Printer* p_;
     bool has_current_range_ = false;
-    Descriptor::ExtensionRange current_combined_range_;
+    int min_start_ = 0;
+    int max_end_ = 0;
   };
 
   // We need to track the largest weak field, because weak fields are serialized
@@ -3909,7 +3909,8 @@ void MessageGenerator::GenerateSerializeWithCachedSizesBody(io::Printer* p) {
          i < ordered_fields.size() || j < sorted_extensions.size();) {
       if ((j == sorted_extensions.size()) ||
           (i < descriptor_->field_count() &&
-           ordered_fields[i]->number() < sorted_extensions[j]->start)) {
+           ordered_fields[i]->number() <
+               sorted_extensions[j]->start_number())) {
         const FieldDescriptor* field = ordered_fields[i++];
         re.Flush();
         if (field->options().weak()) {
@@ -4001,7 +4002,7 @@ void MessageGenerator::GenerateSerializeWithCachedSizesBodyShuffled(
     format("case $1$: {\n", index++);
     format.Indent();
 
-    GenerateSerializeOneExtensionRange(p, r);
+    GenerateSerializeOneExtensionRange(p, r->start_number(), r->end_number());
 
     format("break;\n");
     format.Outdent();
diff --git a/src/google/protobuf/compiler/cpp/message.h b/src/google/protobuf/compiler/cpp/message.h
index 8e6703c9cc..7aead7e980 100644
--- a/src/google/protobuf/compiler/cpp/message.h
+++ b/src/google/protobuf/compiler/cpp/message.h
@@ -147,8 +147,7 @@ class MessageGenerator {
   // Or, if fields.size() == 1, just call GenerateSerializeOneField().
   void GenerateSerializeOneofFields(
       io::Printer* p, const std::vector<const FieldDescriptor*>& fields);
-  void GenerateSerializeOneExtensionRange(
-      io::Printer* p, const Descriptor::ExtensionRange* range);
+  void GenerateSerializeOneExtensionRange(io::Printer* p, int start, int end);
 
   // Generates has_foo() functions and variables for singular field has-bits.
   void GenerateSingularFieldHasBits(const FieldDescriptor* field,
diff --git a/src/google/protobuf/compiler/cpp/parse_function_generator.cc b/src/google/protobuf/compiler/cpp/parse_function_generator.cc
index b28e3b6b82..eda08fce8e 100644
--- a/src/google/protobuf/compiler/cpp/parse_function_generator.cc
+++ b/src/google/protobuf/compiler/cpp/parse_function_generator.cc
@@ -1281,11 +1281,11 @@ void ParseFunctionGenerator::GenerateParseIterationBody(
         if (i > 0) format(" ||\n    ");
 
         uint32_t start_tag = WireFormatLite::MakeTag(
-            range->start, static_cast<WireFormatLite::WireType>(0));
+            range->start_number(), static_cast<WireFormatLite::WireType>(0));
         uint32_t end_tag = WireFormatLite::MakeTag(
-            range->end, static_cast<WireFormatLite::WireType>(0));
+            range->end_number(), static_cast<WireFormatLite::WireType>(0));
 
-        if (range->end > FieldDescriptor::kMaxNumber) {
+        if (range->end_number() > FieldDescriptor::kMaxNumber) {
           format("($1$u <= tag)", start_tag);
         } else {
           format("($1$u <= tag && tag < $2$u)", start_tag, end_tag);
diff --git a/src/google/protobuf/compiler/java/helpers.h b/src/google/protobuf/compiler/java/helpers.h
index c0e503c035..5b2f8fd210 100644
--- a/src/google/protobuf/compiler/java/helpers.h
+++ b/src/google/protobuf/compiler/java/helpers.h
@@ -333,7 +333,7 @@ struct FieldOrderingByNumber {
 struct ExtensionRangeOrdering {
   bool operator()(const Descriptor::ExtensionRange* a,
                   const Descriptor::ExtensionRange* b) const {
-    return a->start < b->start;
+    return a->start_number() < b->start_number();
   }
 };
 
diff --git a/src/google/protobuf/compiler/java/message_serialization.cc b/src/google/protobuf/compiler/java/message_serialization.cc
index fb258b8dc5..a344d7d65b 100644
--- a/src/google/protobuf/compiler/java/message_serialization.cc
+++ b/src/google/protobuf/compiler/java/message_serialization.cc
@@ -42,7 +42,7 @@ namespace java {
 void GenerateSerializeExtensionRange(io::Printer* printer,
                                      const Descriptor::ExtensionRange* range) {
   printer->Print("extensionWriter.writeUntil($end$, output);\n", "end",
-                 absl::StrCat(range->end));
+                 absl::StrCat(range->end_number()));
 }
 
 }  // namespace java
diff --git a/src/google/protobuf/compiler/java/message_serialization.h b/src/google/protobuf/compiler/java/message_serialization.h
index 3b7c8461cb..738ecd6adc 100644
--- a/src/google/protobuf/compiler/java/message_serialization.h
+++ b/src/google/protobuf/compiler/java/message_serialization.h
@@ -78,7 +78,7 @@ void GenerateSerializeFieldsAndExtensions(
     // number of extension ranges without fields in between them.
     const Descriptor::ExtensionRange* range = nullptr;
     while (range_idx < sorted_extensions.size() &&
-           sorted_extensions[range_idx]->end <= field->number()) {
+           sorted_extensions[range_idx]->end_number() <= field->number()) {
       range = sorted_extensions[range_idx++];
     }
 
diff --git a/src/google/protobuf/compiler/objectivec/message.cc b/src/google/protobuf/compiler/objectivec/message.cc
index 5e25b8e02f..4b0ef3e821 100644
--- a/src/google/protobuf/compiler/objectivec/message.cc
+++ b/src/google/protobuf/compiler/objectivec/message.cc
@@ -150,7 +150,7 @@ struct FieldOrderingByStorageSize {
 struct ExtensionRangeOrdering {
   bool operator()(const Descriptor::ExtensionRange* a,
                   const Descriptor::ExtensionRange* b) const {
-    return a->start < b->start;
+    return a->start_number() < b->start_number();
   }
 };
 
@@ -177,10 +177,10 @@ struct SimpleExtensionRange {
     std::vector<SimpleExtensionRange> result;
     result.reserve(sorted_extensions.size());
     for (const auto ext : sorted_extensions) {
-      if (!result.empty() && result.back().end == ext->start) {
-        result.back().end = ext->end;
+      if (!result.empty() && result.back().end == ext->start_number()) {
+        result.back().end = ext->end_number();
       } else {
-        result.emplace_back(ext->start, ext->end);
+        result.emplace_back(ext->start_number(), ext->end_number());
       }
     }
     return result;
diff --git a/src/google/protobuf/compiler/python/generator.cc b/src/google/protobuf/compiler/python/generator.cc
index fc63c34d6b..eb8c381ab6 100644
--- a/src/google/protobuf/compiler/python/generator.cc
+++ b/src/google/protobuf/compiler/python/generator.cc
@@ -702,8 +702,9 @@ void Generator::PrintDescriptor(const Descriptor& message_descriptor) const {
   for (int i = 0; i < message_descriptor.extension_range_count(); ++i) {
     const Descriptor::ExtensionRange* range =
         message_descriptor.extension_range(i);
-    printer_->Print("($start$, $end$), ", "start", absl::StrCat(range->start),
-                    "end", absl::StrCat(range->end));
+    printer_->Print("($start$, $end$), ", "start",
+                    absl::StrCat(range->start_number()), "end",
+                    absl::StrCat(range->end_number()));
   }
   printer_->Print("],\n");
   printer_->Print("oneofs=[\n");