PVS-Studio warning V640 for Chromium

static int memio_buffer_put(....)
{
  ....
  if (len > 0) {
    memcpy(&mb->buf[mb->tail], buf, len);
    mb->tail += len;
    if (mb->tail == mb->bufsize)
       mb->tail = 0;
       transferred += len;
  }
  ....
}

This suspicious code was found in Chromium project by PVS-Studio static code analyzer.
Warning message is:
V640 The code's operational logic does not correspond with its formatting. The statement is indented to the right, but it is always executed. It is possible that curly brackets are missing. nss_memio.c 152

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