zooter68/juju4U: provider/ec2/environ.go; 16 LoC

Found a possible issue in [zooter68/juju4U](https://www.github.com/zooter68/juju4U) at [provider/ec2/environ.go](https://github.com/zooter68/juju4U/blob/a0d745913c35e47c33dc13f0230ee55d9a0e021a/provider/ec2/environ.go#L283-L298)

Below is the message reported by the analyzer for this snippet of code. Beware that the analyzer only reports the first
issue it finds, so please do not limit your consideration to the contents of the below message.

> reference to subnet was used in a composite literal at line 292

[Click here to see the code in its original context.](https://github.com/zooter68/juju4U/blob/a0d745913c35e47c33dc13f0230ee55d9a0e021a/provider/ec2/environ.go#L283-L298)

Click here to show the 16 line(s) of Go which triggered the analyzer.

```go
for _, subnet := range subnetResp.Subnets {
allSubnets = append(allSubnets, fmt.Sprintf("%q:%q", subnet.Id, subnet.CIDRBlock))
if matcher.Match(subnet) {
// We found the CIDR, now see if we can find the AZ
for _, zone := range zones {
if zone.Name() == subnet.AvailZone {
ec2AZ := zone.(*ec2AvailabilityZone)
return &ec2Placement{
availabilityZone: &ec2AZ.AvailabilityZoneInfo,
subnet: &subnet,
}, nil
}
}
logger.Debugf("found a matching subnet (%v) but couldn't find the AZ", subnet)
}
}

```

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See the descriptions of the classifications [here](https://github.com/github-vet/rangeclosure-findings#how-can-i-help) for more information.

commit ID: a0d745913c35e47c33dc13f0230ee55d9a0e021a