Implement pragma(__ctfe)

[thewilsonator]

A pragma declaration to suppress the code generation of functions it is attached to.

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[RazvanN7]

Wouldn't simply making the function a template work?

[thewilsonator]

No, they are already templates. They are called and instantiated at compile time, but not at run time.

[rikkimax]

I stated this on the N.G. thread, but this must tell the .di generator not to elide the function body.

Eliding would require a ton of work to prove it isn't used inside, or exposed outside.

[RazvanN7]

No, they are already templates. They are called and instantiated at compile time, but not at run time.

If the template instances are only used at compile time, I would assume that they will not be codegened.
Last time I looked at the template codegen mechanism it was implemented so that if all instaces are from
speculative contexts then the body does not make it to the object code.

I don't think that this feature is needed. If there are situations where this is useful, then most likely those are compiler bugs.