strange code_warntype output

[JeffBezanson]

julia> function g end;

julia> f() = g();

julia> @code_warntype f()
Variables
  #self#::Core.Compiler.Const(f, false)

Body::Union{}
1 ─     Main.g()
└──     Core.Compiler.Const(:(return %1), false)

Const(:(return %1)) should not be there.

[Keno]

This happens when inference doesn't explore some code paths. For some reason the rest of that code path will get wrapped in Const()

[vtjnash]

Yeah, it should probably use something like Expr(:unreachable, ...) there instead