Fix Issue 18688 - Constructors shouldn't have implicit super call if it throws

[RazvanN7]

The problem with this is that if an assert(false); is encountered the scope of the function in which the assert is located is marked as halt no matter where the assert is located. Let's take for example the bug report:

class A {
    this(int x){}
    @disable this();
}
class B: A {
    this(int x) {
        super(x);
    }
    this(string b) {
        switch(b) {
            case "a":break;
            default: assert(false);
        }
        this(1);
    }
}

When this(1) is semantically analyzed, the scope is not updated to reflect that a constructor call is issued because it is considered that the line is not reachable, due to the assert(false). This is obviously wrong since the code is reachable in some situations. The fix makes it so that the scope is updated to reflect that a this/super call is issued even if inside a halt scope.

[dlang-bot]

Thanks for your pull request and interest in making D better, @RazvanN7! We are looking forward to reviewing it, and you should be hearing from a maintainer soon.
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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	18688	enhancement	Constructors shouldn't have implicit super call if it throws

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "master + dmd#8100"

[WalterBright]

Please add:

// https://issues.dlang.org/show_bug.cgi?id=18688

[WalterBright]

Not needed for compile-only tests

[RazvanN7]

@WalterBright Done. Thank you!

[RazvanN7]

jenkins is failing, but when inspecting the problem looks like all the tests pass. I find the matter puzzling...

Later edit: I restarted the tests, hope this will solve the case

[wilzbach]

If you look at the log (button at the top right), you can see:

[vibe-d/vibe.d+vibe-core-examples] Cannot contact runner-02-gce: hudson.remoting.RequestAbortedException: java.nio.channels.ClosedChannelException
[vibe-d/vibe.d+vibe-core-examples] Could not connect to runner-02-gce to send interrupt signal to process
Cancelling nested steps due to timeout
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] }
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] // dir
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] sh
[vibe-d/vibe.d+vibe-core-examples] ERROR: Issue with creating launcher for agent runner-02-gce. The agent has not been fully initialized yet
[vibe-d/vibe.d+vibe-core-examples] ERROR: Issue with creating launcher for agent runner-02-gce. The agent has not been fully initialized yet
[vibe-d/vibe.d+vibe-core-examples] [Pipeline] [vibe-d/vibe.d+vibe-core-examples] }
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] // withEnv
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] }
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] // ws
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] }
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] // node
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] echo
[vibe-d/vibe.d+vibe-core-examples] java.io.IOException: remote file operation failed: /var/lib/jenkins/dlang_projects@6 at hudson.remoting.Channel@ce5d808:JNLP4-connect connection from 133.132.198.35.bc.googleusercontent.com/35.198.132.133:53510: hudson.remoting.ChannelClosedException: Remote call on JNLP4-connect connection from 133.132.198.35.bc.googleusercontent.com/35.198.132.133:53510 failed. The channel is closing down or has closed down
[Pipeline] [vibe-d/vibe.d+vibe-core-examples] node
[vibe-d/vibe.d+vibe-core-examples] Still waiting to schedule task
[vibe-d/vibe.d+vibe-core-examples] Waiting for next available executor
Body did not finish within grace period; terminating with extreme prejudice

It's some variation of:

• java.nio.channels.ClosedChannelException ci#168
• Cannot contact runner-01-gce: java.lang.InterruptedException ci#136
• ERROR: Issue with creating launcher for agent runner-01-gce. The agent has not been fully initialized yet ci#171
• Increase GCE retries to 3 ci#128 (this has an explanation)

In short: it's due to dlang/ci using cheap preemptible GCE instances which can get terminated while the build runs.
I restarted Jenkins for you.

[wilzbach]

Windows failure is unrelated -> braddr/d-tester#71