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diff --git a/extern/draco/draco/src/draco/core/varint_decoding.h b/extern/draco/draco/src/draco/core/varint_decoding.h
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+++ b/extern/draco/draco/src/draco/core/varint_decoding.h
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+// Copyright 2016 The Draco Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+#ifndef DRACO_CORE_VARINT_DECODING_H_
+#define DRACO_CORE_VARINT_DECODING_H_
+
+#include <type_traits>
+
+#include "draco/core/bit_utils.h"
+#include "draco/core/decoder_buffer.h"
+
+namespace draco {
+
+namespace {
+
+// Decodes a specified unsigned integer as varint. |depth| is the current
+// recursion call depth. The first call to the function must be 1.
+template <typename IntTypeT>
+bool DecodeVarintUnsigned(int depth, IntTypeT *out_val, DecoderBuffer *buffer) {
+  constexpr IntTypeT max_depth = sizeof(IntTypeT) + 1 + (sizeof(IntTypeT) >> 3);
+  if (depth > max_depth) {
+    return false;
+  }
+  // Coding of unsigned values.
+  // 0-6 bit - data
+  // 7 bit - next byte?
+  uint8_t in;
+  if (!buffer->Decode(&in)) {
+    return false;
+  }
+  if (in & (1 << 7)) {
+    // Next byte is available, decode it first.
+    if (!DecodeVarintUnsigned<IntTypeT>(depth + 1, out_val, buffer)) {
+      return false;
+    }
+    // Append decoded info from this byte.
+    *out_val <<= 7;
+    *out_val |= in & ((1 << 7) - 1);
+  } else {
+    // Last byte reached
+    *out_val = in;
+  }
+  return true;
+}
+
+}  // namespace
+
+// Decodes a specified integer as varint. Note that the IntTypeT must be the
+// same as the one used in the corresponding EncodeVarint() call.
+template <typename IntTypeT>
+bool DecodeVarint(IntTypeT *out_val, DecoderBuffer *buffer) {
+  if (std::is_unsigned<IntTypeT>::value) {
+    if (!DecodeVarintUnsigned<IntTypeT>(1, out_val, buffer)) {
+      return false;
+    }
+  } else {
+    // IntTypeT is a signed value. Decode the symbol and convert to signed.
+    typename std::make_unsigned<IntTypeT>::type symbol;
+    if (!DecodeVarintUnsigned(1, &symbol, buffer)) {
+      return false;
+    }
+    *out_val = ConvertSymbolToSignedInt(symbol);
+  }
+  return true;
+}
+
+}  // namespace draco
+
+#endif  // DRACO_CORE_VARINT_DECODING_H_