PVS-Studio warning V636 for libevent

static int cfg_grouplimit = 0;
static int cfg_n_connections = 30;

static int
test_ratelimiting(void)
{
  double expected_avg_persec = -1.0;
  ....
  expected_avg_persec = cfg_grouplimit / cfg_n_connections;
  ....
}

This suspicious code was found in libevent project by PVS-Studio static code analyzer.
Warning message is:
V636 The 'cfg_grouplimit / cfg_n_connections' expression was implicitly casted from 'int' type to 'double' type. Consider utilizing an explicit type cast to avoid the loss of a fractional part. An example: double A = (double)(X) / Y;. test-ratelim.c 242

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