What were you expecting to happen?

I expect the documentation for the CLI to plainly state the semantics of listing more than one task.

https://github.com/gulpjs/gulp/blob/master/docs/CLI.md

In more detail, this documentation should state whether, when multiple tasks are listed, they will be executed concurrently, or sequentially. Here is a common practical application. Imagine I have a task "clean" and a task "build". Is it valid to run the command "gulp clean build"? If the semantics were specified, then I could answer this question.

What actually happened?

It does not specify the semantics. It says only "Tasks can be executed by running gulp ."

Please post a sample of your gulpfile (preferably reduced to just the bit that's not working)

n/a, looking at the current CLI documentation linked above.

What version of gulp are you using?

n/a, looking at the current CLI documentation linked above.

What versions of npm and node are you using?

n/a, looking at the current CLI documentation linked above.