And on top of that, we're going to build a tool that isolates such cause effect chamge automatically.

Computer glitch.

What's happened to us? A malfunction of some sort.

Is there something wrong?

We can pick choices for x that make things cancel out nicely.

Famous detective solves baffling disappearance.

It's not a bug. It's a misfeature.

If we can change a variable value such that the failure goes away, we do have a failure cause.

Okay, let's give this all a test.

This minimal subset then at the given location is the variable that causes the failure.

The basic idea is as follows

On top of that, we're going to build a tool that makes you infer assertions from executions.

Now let's see what they did in step 2.

It simply means that after any fix you need to verify whether your fix actually did the trick and better yet before the fix, you should be able to precisely predict that your change will actually fix the failure.

Please include the debugging output in your problem report.

I was just following up to make sure phones are okay.

Again, we can use delta debugging to simplify this.

It is impossible to resolve the conflict.

How are you?

How you feeling?

How are you feeling?

You okay?

non recoverable failure in name resolution

It is not the case that every defect always can cause a failure because defects cannot be an unreachable code and therefore, they may not cause a failure.

Here is developer Dora.

This was the original differential equation.

Right! gt gt And so all of a sudden, you've got half your app servers with a different configuration.

Are you feeling okay?

Feels good Feels good

How you feeling,grandpa?

Hey. How do you feel?

On Macs, Safari supports WebGL but you'll have to do a little twiddle to enable it. Linux has it's own issues.

Because there's something wrong with you.

I'd like to sit down with you,see how we can work this out.

Here's a quiz. I invoke the GNU compiler, and it crashes.

Oh, when Hickman worries, you worry?

And the same tests for the electrical system and the toilets.

Are you feeling under the weather?

Twistiness

And now we can see what happens.

Are you ill?

Well, how bad is he?

How would you like it?

You don't.

How are your legs?