PVS-Studio warning V567 for Scilab

static char **replaceStrings(....)
{
  ....
  int i = 0;
  ....
  for (i = 0; i < nr; i = i++)
  ....
}

This suspicious code was found in Scilab project by PVS-Studio static code analyzer.
Warning message is:
V567 Undefined behavior. The 'i' variable is modified while being used twice between sequence points. csvread.c 620

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