Fix freebsd build.

It turns out system headers included by generated plugin.pb.h file already contains
major/minor macro definitions when built on FreeBSD and we need to add #undefs to
the generated header file.

This change also fixes another compile error regarding EXPECT_DEATH on FreeBSD.

src/google/protobuf/compiler/cpp/cpp_file.cc

@@ -54,6 +54,39 @@ namespace google {
 namespace protobuf {
 namespace compiler {
 namespace cpp {
+namespace {
+// The list of names that are defined as macros on some platforms. We need to
+// #undef them for the generated code to compile.
+const char* kMacroNames[] = {"major", "minor"};
+
+bool IsMacroName(const string& name) {
+  // Just do a linear search as the number of elements is very small.
+  for (int i = 0; i < GOOGLE_ARRAYSIZE(kMacroNames); ++i) {
+    if (name == kMacroNames[i]) return true;
+  }
+  return false;
+}
+
+void CollectMacroNames(const Descriptor* message, vector<string>* names) {
+  for (int i = 0; i < message->field_count(); ++i) {
+    const FieldDescriptor* field = message->field(i);
+    if (IsMacroName(field->name())) {
+      names->push_back(field->name());
+    }
+  }
+  for (int i = 0; i < message->nested_type_count(); ++i) {
+    CollectMacroNames(message->nested_type(i), names);
+  }
+}
+
+void CollectMacroNames(const FileDescriptor* file, vector<string>* names) {
+  for (int i = 0; i < file->message_type_count(); ++i) {
+    CollectMacroNames(file->message_type(i), names);
+  }
+}
+
+
+}  // namespace
 
 // ===================================================================
 
@@ -103,10 +136,23 @@ FileGenerator::FileGenerator(const FileDescriptor* file, const Options& options)
 
 FileGenerator::~FileGenerator() {}
 
+void FileGenerator::GenerateMacroUndefs(io::Printer* printer) {
+  vector<string> names_to_undef;
+  CollectMacroNames(file_, &names_to_undef);
+  for (int i = 0; i < names_to_undef.size(); ++i) {
+    printer->Print(
+        "#ifdef $name$\n"
+        "#undef $name$\n"
+        "#endif\n",
+        "name", names_to_undef[i]);
+  }
+}
+
 void FileGenerator::GenerateHeader(io::Printer* printer) {
   printer->Print(
     "// @@protoc_insertion_point(includes)\n");
 
+  GenerateMacroUndefs(printer);
 
   GenerateForwardDeclarations(printer);
 

src/google/protobuf/compiler/cpp/cpp_file.h

@@ -133,6 +133,15 @@ class FileGenerator {
 
   void GenerateProto2NamespaceEnumSpecializations(io::Printer* printer);
 
+  // Sometimes the names we use in a .proto file happen to be defined as macros
+  // on some platforms (e.g., macro/minor used in plugin.proto are defined as
+  // macros in sys/types.h on FreeBSD and a few other platforms). To make the
+  // generated code compile on these platforms, we either have to undef the
+  // macro for these few platforms, or rename the field name for all platforms.
+  // Since these names are part of protobuf public API, renaming is generally
+  // a breaking change so we prefer the #undef approach.
+  void GenerateMacroUndefs(io::Printer* printer);
+
   const FileDescriptor* file_;
   const Options options_;
 

src/google/protobuf/compiler/plugin.pb.h

@@ -30,6 +30,12 @@
 #include <google/protobuf/unknown_field_set.h>
 #include <google/protobuf/descriptor.pb.h>
 // @@protoc_insertion_point(includes)
+#ifdef major
+#undef major
+#endif
+#ifdef minor
+#undef minor
+#endif
 namespace google {
 namespace protobuf {
 class DescriptorProto;

src/google/protobuf/stubs/stringpiece_unittest.cc

@@ -783,11 +783,13 @@ TEST(FindOneCharTest, EdgeCases) {
   EXPECT_EQ(StringPiece::npos, a.rfind('x'));
 }
 
+#ifdef PROTOBUF_HAS_DEATH_TEST
 #ifndef NDEBUG
 TEST(NonNegativeLenTest, NonNegativeLen) {
   EXPECT_DEATH(StringPiece("xyz", -1), "len >= 0");
 }
 #endif  // ndef DEBUG
+#endif  // PROTOBUF_HAS_DEATH_TEST
 
 }  // namespace
 }  // namespace protobuf