PVS-Studio warning V597 for TortoiseSVN

static void sha_mpint(SHA_State * s, Bignum b)
{
  unsigned char lenbuf[4];
  ....
  memset(lenbuf, 0, sizeof(lenbuf));
}

This suspicious code was found in TortoiseSVN project by PVS-Studio static code analyzer.
Warning message is:
V597 The compiler could delete the 'memset' function call, which is used to flush 'lenbuf' buffer. The RtlSecureZeroMemory() function should be used to erase the private data. sshdss.c 23

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