inferred type for eachline() is lost in v0.6

[ghost]

julia> Base.Test.@inferred eachline(STDIN)
ERROR: return type EachLine does not match inferred return type Any
Stacktrace:
 [1] error(::String) at ./error.jl:21

julia> versioninfo()
Julia Version 0.6.0-dev.2481
Commit 2d86c42* (2017-01-30 22:50 UTC)

works fine in v0.5

julia> Base.Test.@inferred eachline(STDIN)
EachLine(Base.TTY(open, 0 bytes waiting),Base.#281)

julia> versioninfo()
Julia Version 0.5.0
Commit 3c9d753* (2016-09-19 18:14 UTC)

and then when used in a loop the eltype() is not known either:

julia> f() = for k in eachline(STDIN); @show k; end
f (generic function with 2 methods)

julia> @code_warntype f()
Variables:
  #self#::#f
  k::Any
  value::Any
  #temp#::Any

Body:
  begin 
      SSAValue(0) = (Main.eachline)(Main.STDIN)::Any
      #temp#::Any = (Base.start)(SSAValue(0))::Any
      3: 
      unless !((Base.done)(SSAValue(0),#temp#::Any)::Any)::Any goto 26
      SSAValue(1) = (Base.next)(SSAValue(0),#temp#::Any)::Any
      k::Any = (Core.getfield)(SSAValue(1),1)::Any
      #temp#::Any = (Core.getfield)(SSAValue(1),2)::Any # line 1:
      SSAValue(2) = "k = "
      # meta: location show.jl # line 251:

[pabloferz]

Should get fixed by #20345

[JeffBezanson]

Sadly it won't; that PR doesn't affect inference.

[pabloferz]

Well, this is easy enough to fix (work around), so #20356...