PVS-Studio warning V579 for TPP

void Out2XML::writeOutData() {
  ...
  // assume a string of less than
  // 9 characters will represent the charge state
  char *chg=(char*)malloc(10 * sizeof(char));
  // zero-fill the rest of the array
  strncpy(chg, "1", sizeof(chg));
  ...
}

This suspicious code was found in TPP project by PVS-Studio static code analyzer.
Warning message is:
V579 The strncpy function receives the pointer and its size as arguments. It is possibly a mistake. Inspect the third argument. CombineOut out2xml.cxx 210

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