Marked another compiler literal unsigned.

When compiling a protobuf with gcc 4.1.2 for powerpc, I ran into
another of the following warning message:

INFO: From Compiling my_proto.pb.cc powerpc-603e-linux-gcc:
bazel-out/local_linux-dbg/genfiles/my_proto.pb.cc: In member
   function `virtual void MyProto::Clear()':
   bazel-out/local_linux-dbg/genfiles/my_proto.pb.cc:223: warning: this
      decimal constant is unsigned only in ISO C90

The line in the proto file that was triggering it was:

  if (_has_bits_[24 / 32] & 4278190080) {
    ZR_(field1_, field2_);
  }

_has_bits_ is a uint32.  The constant mask should therefore be
unsigned.  This change updates the constant to be generated as
unsigned.

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

@@ -3510,7 +3510,7 @@ GenerateByteSize(io::Printer* printer) {
         } else {
           if (HasFieldPresence(descriptor_->file())) {
             printer->Print(
-              "if (_has_bits_[$index$ / 32] & $mask$) {\n",
+              "if (_has_bits_[$index$ / 32] & $mask$u) {\n",
               "index", SimpleItoa(i),
               "mask", SimpleItoa(mask));
             printer->Indent();

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

@@ -913,7 +913,7 @@ void CodeGeneratorResponse_File::SerializeWithCachedSizes(
 int CodeGeneratorResponse_File::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 7) {
+  if (_has_bits_[0 / 32] & 7u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +

src/google/protobuf/descriptor.pb.cc

@@ -1648,7 +1648,7 @@ void FileDescriptorProto::SerializeWithCachedSizes(
 int FileDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 3) {
+  if (_has_bits_[0 / 32] & 3u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -1664,7 +1664,7 @@ int FileDescriptorProto::ByteSize() const {
     }
 
   }
-  if (_has_bits_[9 / 32] & 3584) {
+  if (_has_bits_[9 / 32] & 3584u) {
     // optional .google.protobuf.FileOptions options = 8;
     if (has_options()) {
       total_size += 1 +
@@ -2534,7 +2534,7 @@ void DescriptorProto_ExtensionRange::SerializeWithCachedSizes(
 int DescriptorProto_ExtensionRange::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 3) {
+  if (_has_bits_[0 / 32] & 3u) {
     // optional int32 start = 1;
     if (has_start()) {
       total_size += 1 +
@@ -2817,7 +2817,7 @@ void DescriptorProto_ReservedRange::SerializeWithCachedSizes(
 int DescriptorProto_ReservedRange::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 3) {
+  if (_has_bits_[0 / 32] & 3u) {
     // optional int32 start = 1;
     if (has_start()) {
       total_size += 1 +
@@ -3373,7 +3373,7 @@ void DescriptorProto::SerializeWithCachedSizes(
 int DescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 129) {
+  if (_has_bits_[0 / 32] & 129u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -4558,7 +4558,7 @@ void FieldDescriptorProto::SerializeWithCachedSizes(
 int FieldDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 255) {
+  if (_has_bits_[0 / 32] & 255u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -5633,7 +5633,7 @@ void EnumDescriptorProto::SerializeWithCachedSizes(
 int EnumDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 5) {
+  if (_has_bits_[0 / 32] & 5u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -6102,7 +6102,7 @@ void EnumValueDescriptorProto::SerializeWithCachedSizes(
 int EnumValueDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 7) {
+  if (_has_bits_[0 / 32] & 7u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -6569,7 +6569,7 @@ void ServiceDescriptorProto::SerializeWithCachedSizes(
 int ServiceDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 5) {
+  if (_has_bits_[0 / 32] & 5u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -7165,7 +7165,7 @@ void MethodDescriptorProto::SerializeWithCachedSizes(
 int MethodDescriptorProto::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 63) {
+  if (_has_bits_[0 / 32] & 63u) {
     // optional string name = 1;
     if (has_name()) {
       total_size += 1 +
@@ -8240,7 +8240,7 @@ void FileOptions::SerializeWithCachedSizes(
 int FileOptions::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 255) {
+  if (_has_bits_[0 / 32] & 255u) {
     // optional string java_package = 1;
     if (has_java_package()) {
       total_size += 1 +
@@ -8289,7 +8289,7 @@ int FileOptions::ByteSize() const {
     }
 
   }
-  if (_has_bits_[8 / 32] & 16128) {
+  if (_has_bits_[8 / 32] & 16128u) {
     // optional bool java_generic_services = 17 [default = false];
     if (has_java_generic_services()) {
       total_size += 2 + 1;
@@ -9279,7 +9279,7 @@ void MessageOptions::SerializeWithCachedSizes(
 int MessageOptions::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 15) {
+  if (_has_bits_[0 / 32] & 15u) {
     // optional bool message_set_wire_format = 1 [default = false];
     if (has_message_set_wire_format()) {
       total_size += 1 + 1;
@@ -9939,7 +9939,7 @@ void FieldOptions::SerializeWithCachedSizes(
 int FieldOptions::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 63) {
+  if (_has_bits_[0 / 32] & 63u) {
     // optional .google.protobuf.FieldOptions.CType ctype = 1 [default = STRING];
     if (has_ctype()) {
       total_size += 1 +
@@ -10498,7 +10498,7 @@ void EnumOptions::SerializeWithCachedSizes(
 int EnumOptions::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[0 / 32] & 3) {
+  if (_has_bits_[0 / 32] & 3u) {
     // optional bool allow_alias = 2;
     if (has_allow_alias()) {
       total_size += 1 + 1;
@@ -12410,7 +12410,7 @@ void UninterpretedOption::SerializeWithCachedSizes(
 int UninterpretedOption::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[1 / 32] & 126) {
+  if (_has_bits_[1 / 32] & 126u) {
     // optional string identifier_value = 3;
     if (has_identifier_value()) {
       total_size += 1 +
@@ -13248,7 +13248,7 @@ void SourceCodeInfo_Location::SerializeWithCachedSizes(
 int SourceCodeInfo_Location::ByteSize() const {
   int total_size = 0;
 
-  if (_has_bits_[2 / 32] & 12) {
+  if (_has_bits_[2 / 32] & 12u) {
     // optional string leading_comments = 3;
     if (has_leading_comments()) {
       total_size += 1 +