protobuf-c 1.3.1 issue with PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE

README.md

Software versions:

• Protobuf - 3.6.1
• Protobuf-c - 1.3.1

Commands ran:

$protoc --c_out=. enum_int_test.proto . 

$ gcc enum_int_test.c  
In file included from enum_int_test.pb-c.h:7:0,  
                 from enum_int_test.c:1:  
enum_int_test.pb-c.h:35:5: error: redeclaration of enumerator ‘_ENUM_INT_TEST__LABEL_IS_INT_SIZE’ . 
     PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE(ENUM_INT_TEST__LABEL) 
     ^
enum_int_test.pb-c.h:26:5: note: previous definition of ‘_ENUM_INT_TEST__LABEL_IS_INT_SIZE’ was here
     PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE(ENUM_INT_TEST__LABEL)
     ^

enum_int_test.c

#include "enum_int_test.pb-c.h"

int main(){
    return 0;
}

enum_int_test.pb-c.c

/* Generated by the protocol buffer compiler.  DO NOT EDIT! */
/* Generated from: enum_int_test.proto */

/* Do not generate deprecated warnings for self */
#ifndef PROTOBUF_C__NO_DEPRECATED
#define PROTOBUF_C__NO_DEPRECATED
#endif

#include "enum_int_test.pb-c.h"
void   enum_int_test__init
                     (EnumIntTest         *message)
{
  static const EnumIntTest init_value = ENUM_INT_TEST__INIT;
  *message = init_value;
}
size_t enum_int_test__get_packed_size
                     (const EnumIntTest *message)
{
  assert(message->base.descriptor == &enum_int_test__descriptor);
  return protobuf_c_message_get_packed_size ((const ProtobufCMessage*)(message));
}
size_t enum_int_test__pack
                     (const EnumIntTest *message,
                      uint8_t       *out)
{
  assert(message->base.descriptor == &enum_int_test__descriptor);
  return protobuf_c_message_pack ((const ProtobufCMessage*)message, out);
}
size_t enum_int_test__pack_to_buffer
                     (const EnumIntTest *message,
                      ProtobufCBuffer *buffer)
{
  assert(message->base.descriptor == &enum_int_test__descriptor);
  return protobuf_c_message_pack_to_buffer ((const ProtobufCMessage*)message, buffer);
}
EnumIntTest *
       enum_int_test__unpack
                     (ProtobufCAllocator  *allocator,
                      size_t               len,
                      const uint8_t       *data)
{
  return (EnumIntTest *)
     protobuf_c_message_unpack (&enum_int_test__descriptor,
                                allocator, len, data);
}
void   enum_int_test__free_unpacked
                     (EnumIntTest *message,
                      ProtobufCAllocator *allocator)
{
  if(!message)
    return;
  assert(message->base.descriptor == &enum_int_test__descriptor);
  protobuf_c_message_free_unpacked ((ProtobufCMessage*)message, allocator);
}
static const ProtobufCEnumValue enum_int_test__label__enum_values_by_number[2] =
{
  { "LABEL_1", "ENUM_INT_TEST__LABEL__LABEL_1", 0 },
  { "LABEL_2", "ENUM_INT_TEST__LABEL__LABEL_2", 1 },
};
static const ProtobufCIntRange enum_int_test__label__value_ranges[] = {
{0, 0},{0, 2}
};
static const ProtobufCEnumValueIndex enum_int_test__label__enum_values_by_name[2] =
{
  { "LABEL_1", 0 },
  { "LABEL_2", 1 },
};
const ProtobufCEnumDescriptor enum_int_test__label__descriptor =
{
  PROTOBUF_C__ENUM_DESCRIPTOR_MAGIC,
  "EnumIntTest.Label",
  "Label",
  "EnumIntTest__Label",
  "",
  2,
  enum_int_test__label__enum_values_by_number,
  2,
  enum_int_test__label__enum_values_by_name,
  1,
  enum_int_test__label__value_ranges,
  NULL,NULL,NULL,NULL   /* reserved[1234] */
};
static const ProtobufCFieldDescriptor enum_int_test__field_descriptors[2] =
{
  {
    "label_label",
    123,
    PROTOBUF_C_LABEL_NONE,
    PROTOBUF_C_TYPE_ENUM,
    offsetof(EnumIntTest, label_case),
    offsetof(EnumIntTest, label_label),
    &enum_int_test__label__descriptor,
    NULL,
    0 | PROTOBUF_C_FIELD_FLAG_ONEOF,             /* flags */
    0,NULL,NULL    /* reserved1,reserved2, etc */
  },
  {
    "label_uint64",
    124,
    PROTOBUF_C_LABEL_NONE,
    PROTOBUF_C_TYPE_UINT64,
    offsetof(EnumIntTest, label_case),
    offsetof(EnumIntTest, label_uint64),
    NULL,
    NULL,
    0 | PROTOBUF_C_FIELD_FLAG_ONEOF,             /* flags */
    0,NULL,NULL    /* reserved1,reserved2, etc */
  },
};
static const unsigned enum_int_test__field_indices_by_name[] = {
  0,   /* field[0] = label_label */
  1,   /* field[1] = label_uint64 */
};
static const ProtobufCIntRange enum_int_test__number_ranges[1 + 1] =
{
  { 123, 0 },
  { 0, 2 }
};
const ProtobufCMessageDescriptor enum_int_test__descriptor =
{
  PROTOBUF_C__MESSAGE_DESCRIPTOR_MAGIC,
  "EnumIntTest",
  "EnumIntTest",
  "EnumIntTest",
  "",
  sizeof(EnumIntTest),
  2,
  enum_int_test__field_descriptors,
  enum_int_test__field_indices_by_name,
  1,  enum_int_test__number_ranges,
  (ProtobufCMessageInit) enum_int_test__init,
  NULL,NULL,NULL    /* reserved[123] */
};

enum_int_test.pb-c.h

/* Generated by the protocol buffer compiler.  DO NOT EDIT! */
/* Generated from: enum_int_test.proto */

#ifndef PROTOBUF_C_enum_5fint_5ftest_2eproto__INCLUDED
#define PROTOBUF_C_enum_5fint_5ftest_2eproto__INCLUDED

#include <protobuf-c/protobuf-c.h>

PROTOBUF_C__BEGIN_DECLS

#if PROTOBUF_C_VERSION_NUMBER < 1003000
# error This file was generated by a newer version of protoc-c which is incompatible with your libprotobuf-c headers. Please update your headers.
#elif 1003001 < PROTOBUF_C_MIN_COMPILER_VERSION
# error This file was generated by an older version of protoc-c which is incompatible with your libprotobuf-c headers. Please regenerate this file with a newer version of protoc-c.
#endif


typedef struct _EnumIntTest EnumIntTest;


/* --- enums --- */

typedef enum _EnumIntTest__Label {
  ENUM_INT_TEST__LABEL__LABEL_1 = 0,
  ENUM_INT_TEST__LABEL__LABEL_2 = 1
    PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE(ENUM_INT_TEST__LABEL)
} EnumIntTest__Label;

/* --- messages --- */

typedef enum {
  ENUM_INT_TEST__LABEL__NOT_SET = 0,
  ENUM_INT_TEST__LABEL_LABEL_LABEL = 123,
  ENUM_INT_TEST__LABEL_LABEL_UINT64 = 124
    PROTOBUF_C__FORCE_ENUM_TO_BE_INT_SIZE(ENUM_INT_TEST__LABEL)
} EnumIntTest__LabelCase;

struct  _EnumIntTest
{
  ProtobufCMessage base;
  EnumIntTest__LabelCase label_case;
  union {
    EnumIntTest__Label label_label;
    uint64_t label_uint64;
  };
};
#define ENUM_INT_TEST__INIT \
 { PROTOBUF_C_MESSAGE_INIT (&enum_int_test__descriptor) \
    , ENUM_INT_TEST__LABEL__NOT_SET, {0} }


/* EnumIntTest methods */
void   enum_int_test__init
                     (EnumIntTest         *message);
size_t enum_int_test__get_packed_size
                     (const EnumIntTest   *message);
size_t enum_int_test__pack
                     (const EnumIntTest   *message,
                      uint8_t             *out);
size_t enum_int_test__pack_to_buffer
                     (const EnumIntTest   *message,
                      ProtobufCBuffer     *buffer);
EnumIntTest *
       enum_int_test__unpack
                     (ProtobufCAllocator  *allocator,
                      size_t               len,
                      const uint8_t       *data);
void   enum_int_test__free_unpacked
                     (EnumIntTest *message,
                      ProtobufCAllocator *allocator);
/* --- per-message closures --- */

typedef void (*EnumIntTest_Closure)
                 (const EnumIntTest *message,
                  void *closure_data);

/* --- services --- */


/* --- descriptors --- */

extern const ProtobufCMessageDescriptor enum_int_test__descriptor;
extern const ProtobufCEnumDescriptor    enum_int_test__label__descriptor;

PROTOBUF_C__END_DECLS


#endif  /* PROTOBUF_C_enum_5fint_5ftest_2eproto__INCLUDED */

enum_int_test.proto

syntax = "proto3";

message EnumIntTest {
  enum Label {
    LABEL_1 = 0;
    LABEL_2 = 1;
  }
  oneof label {
    Label label_label = 123;
    uint64 label_uint64 = 124;
  }
}