#!/bin/sh -eu
# Each non-top-level build rule not writing to a target must yield a warning.

>all.do printf 'redo-ifchange a
'

>a.do printf 'redo-ifchange b
'

>b.do :

2>stderr redo
<stderr grep -q 'a: nothing written to target'
<stderr grep -q 'b: nothing written to target'
