busybox

grep: make "-f -" work (+ testsuite)
diff: small code shrink

function                                             old     new   delta
grep_main                                            722     714      -8
diffreg                                             1825    1793     -32
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(add/remove: 0/0 grow/shrink: 0/2 up/down: 0/-40)             Total: -40 bytes