bug in zsh wait builtin - rhbz#1150541

[Tim Speetjens <tim.speetjens@xxxxxxxxx>]

Dear zsh workers,

I'ld like to report a bug originally filed in
https://bugzilla.redhat.com/show_bug.cgi?id=1150541 which is still present
in the latest version, 5.0.7

Title:
zsh wait builtin shows an error and doesn't propagate exit code for a
finished child process

Description of problem:
When a child process is started, and finished before a call to wait, an
error is signaled. Also the exit code for wait is 1, where it should be the
exit code of the child process

Version-Release number of selected component:
zsh-4.3.10-7 (rhel6, x86_64)
zsh-5.0.2-7 (rhel7, x86_64)
zsh 5.0.7 (f21 rawhide, x86_64)
zsh 5.0.7 from source

How reproducible:
100%

Steps to Reproduce:
Run the following script with zsh (or with zsh in ksh emulation mode):
#!/bin/ksh
sh -c "echo done" &
pid1=$!
sleep 1
wait $pid1
echo "rc: $?"

sh -c "exit 3" &
pid2=$!
sleep 1
wait $pid2
echo "rc: $?"

Actual results:
$ zsh test.sh
done
test.sh:wait:5: pid 6156 is not a child of this shell
rc: 1
test.sh:wait:11: pid 6159 is not a child of this shell
rc: 1


Expected results (also seen when running the script with bash or mksh):
$ zsh test.sh
done
rc: 0
rc: 3


Kind regards
Tim Speetjens