1 files changed, 30 insertions, 0 deletions
diff --git a/src/rocksdb/util/gflags_compat.h b/src/rocksdb/util/gflags_compat.h
new file mode 100644
index 000000000..b6f88a5bc
--- /dev/null
+++ b/src/rocksdb/util/gflags_compat.h
@@ -0,0 +1,30 @@
+//  Copyright (c) 2017-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#pragma once
+#include <gflags/gflags.h>
+
+#include <functional>
+
+#ifndef GFLAGS_NAMESPACE
+// in case it's not defined in old versions, that's probably because it was
+// still google by default.
+#define GFLAGS_NAMESPACE google
+#endif
+
+#ifndef DEFINE_uint32
+// DEFINE_uint32 does not appear in older versions of gflags. This should be
+// a sane definition for those versions.
+#include <cstdint>
+#define DEFINE_uint32(name, val, txt)             \
+  namespace gflags_compat {                       \
+  DEFINE_int32(name, val, txt);                   \
+  }                                               \
+  std::reference_wrapper<uint32_t> FLAGS_##name = \
+      std::ref(*reinterpret_cast<uint32_t *>(&gflags_compat::FLAGS_##name));
+
+#define DECLARE_uint32(name) \
+  extern std::reference_wrapper<uint32_t> FLAGS_##name;
+#endif  // !DEFINE_uint32