message: Fix FlexBuffers writing incomplete length for 64-bit vectors.
diff: @@ -1088,8 +1088,8 @@ class Builder FLATBUFFERS_FINAL_CLASS {
  reinterpret_cast<const uint8_t *>(val) + size);
  }
  - // For values T >= byte_width
  template<typename T> void Write(T val, size_t byte_width) {
  + assert(sizeof(T) >= byte_width);
  val = flatbuffers::EndianScalar(val);
  WriteBytes(&val, byte_width);
  }
  @@ -1239,7 +1239,7 @@ class Builder FLATBUFFERS_FINAL_CLASS {
  // TODO: instead of asserting, could write vector with larger elements
  // instead, though that would be wasteful.
  assert(WidthU(len) <= bit_width);
  - if (!fixed) Write(len, byte_width);
  + if (!fixed) Write<uint64_t>(len, byte_width);
  auto vloc = buf_.size();
  for (size_t i = 0; i < len; i++) Write(elems[i], byte_width);
  stack_.push_back(Value(static_cast<uint64_t>(vloc),
  @@ -1281,9 +1281,9 @@ class Builder FLATBUFFERS_FINAL_CLASS {
  // Write vector. First the keys width/offset if available, and size.
  if (keys) {
  WriteOffset(keys->u_, byte_width);
  - Write(1U << keys->min_bit_width_, byte_width);
  + Write<uint64_t>(1U << keys->min_bit_width_, byte_width);
  }
  - if (!fixed) Write(vec_len, byte_width);
  + if (!fixed) Write<uint64_t>(vec_len, byte_width);
  // Then the actual data.
  auto vloc = buf_.size();
  for (size_t i = start; i < stack_.size(); i += step) {
  