all/any return the wrong result when reducing over infinite iterators

[Seelengrab]

This is a bit of an odd one:

julia> f() = any(isone, Iterators.repeated(0))

should clearly return false or loop infinitely, yet:

julia> @code_typed f()
CodeInfo(
1 ─     return true
) => Bool

The inverse happens with all:

julia> f() = all(iszero, Iterators.repeated(0))
f (generic function with 1 method)

julia> @code_lowered f()
CodeInfo(
1 ─ %1 = Main.iszero
│   %2 = Base.Iterators.repeated
│   %3 = (%2)(0)
│   %4 = Main.all(%1, %3)
└──      return %4
)

julia> @code_typed f()
CodeInfo(
1 ─     return false
) => Bool

which should (if anything) return true.

Seems like an issue in inference:

julia> @code_warntype f()
MethodInstance for f()
  from f() @ Main REPL[1]:1
Arguments
  #self#::Core.Const(f)
Body::Bool
1 ─ %1 = Main.iszero::Core.Const(iszero)
│   %2 = Base.getproperty(Main.Iterators, :repeated)::Core.Const(Base.Iterators.repeated)
│   %3 = (%2)(0)::Core.Const(Base.Iterators.Repeated{Int64}(0))
│   %4 = Main.all(%1, %3)::Core.Const(false)
└──      return %4

[KristofferC]

Ref #40009

[JeffBezanson]

Yes, this is a duplicate of #40009. I do really think we should change it, and Keno seems to agree.