REPL sometimes breaks after printing is interrupted

[pwstokes225]

On v1.2.0-rc3, I have issues interrupting the following with Ctrl+C:

julia> while true
       print('.')
       end

Doing so often gives the following warning/error, after which the REPL becomes unusable:

WARNING: Workqueue inconsistency detected: popfirst!(Workqueue).state != :runnable
ERROR: InterruptException:
Stacktrace:
 [1] poptaskref(::Base.InvasiveLinkedListSynchronized{Task}) at ./task.jl:564
 [2] wait() at ./task.jl:591
 [3] uv_write(::Base.TTY, ::Ptr{UInt8}, ::UInt64) at ./stream.jl:883
 [4] unsafe_write(::Base.TTY, ::Ptr{UInt8}, ::UInt64) at ./stream.jl:931
 [5] unsafe_write at ./io.jl:522 [inlined]
 [6] unsafe_write(::Base.TTY, ::Base.RefValue{UInt8}, ::Int64) at ./io.jl:520
 [7] write at ./io.jl:523 [inlined]
 [8] write(::Base.TTY, ::UInt8) at ./stream.jl:973
 [9] write at ./io.jl:576 [inlined]
 [10] print(::Base.TTY, ::Char) at ./char.jl:229
 [11] print(::Char) at ./coreio.jl:3
 [12] top-level scope at ./REPL[1]:2

Other times I get this error, after which the REPL still works but Ctrl+C no longer interrupts things:

ERROR: schedule: Task not runnable
Stacktrace:
 [1] error(::String) at ./error.jl:33
 [2] enq_work(::Task) at ./task.jl:411
 [3] schedule at ./task.jl:426 [inlined]
 [4] uv_writecb_task(::Ptr{Nothing}, ::Int32) at ./stream.jl:985
 [5] process_events at ./libuv.jl:98 [inlined]
 [6] wait() at ./task.jl:593
 [7] wait(::Base.GenericCondition{ReentrantLock}) at ./condition.jl:104
 [8] take_buffered(::Channel{Any}) at ./channels.jl:350
 [9] take!(::Channel{Any}) at ./channels.jl:344
 [10] eval_with_backend(::Any, ::REPL.REPLBackendRef) at /home/peter/julia/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:700
 [11] (::getfield(REPL, Symbol("#do_respond#38")){Bool,getfield(REPL, Symbol("##48#57")){REPL.LineEditREPL,REPL.REPLHistoryProvider},REPL.LineEditREPL,REPL.LineEdit.Prompt})(::Any, ::Any, ::Any) at /home/peter/julia/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:714
 [12] #invokelatest#1 at ./essentials.jl:790 [inlined]
 [13] invokelatest at ./essentials.jl:789 [inlined]
 [14] run_interface(::REPL.Terminals.TextTerminal, ::REPL.LineEdit.ModalInterface, ::REPL.LineEdit.MIState) at /home/peter/julia/usr/share/julia/stdlib/v1.2/REPL/src/LineEdit.jl:2306
 [15] run_frontend(::REPL.LineEditREPL, ::REPL.REPLBackendRef) at /home/peter/julia/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:1038
 [16] run_repl(::REPL.AbstractREPL, ::Any) at /home/peter/julia/usr/share/julia/stdlib/v1.2/REPL/src/REPL.jl:201
 [17] (::getfield(Base, Symbol("##737#739")){Bool,Bool,Bool,Bool})(::Module) at ./client.jl:390
 [18] #invokelatest#1 at ./essentials.jl:790 [inlined]
 [19] invokelatest at ./essentials.jl:789 [inlined]
 [20] run_main_repl(::Bool, ::Bool, ::Bool, ::Bool, ::Bool) at ./client.jl:374
 [21] exec_options(::Base.JLOptions) at ./client.jl:312
 [22] _start() at ./client.jl:464

Finally, sometimes interrupting works as expected (without any noticeable issues):

ERROR: InterruptException:
Stacktrace:
 [1] process_events at ./libuv.jl:98 [inlined]
 [2] wait() at ./task.jl:593
 [3] uv_write(::Base.TTY, ::Ptr{UInt8}, ::UInt64) at ./stream.jl:883
 [4] unsafe_write(::Base.TTY, ::Ptr{UInt8}, ::UInt64) at ./stream.jl:931
 [5] unsafe_write at ./io.jl:522 [inlined]
 [6] unsafe_write(::Base.TTY, ::Base.RefValue{UInt8}, ::Int64) at ./io.jl:520
 [7] write at ./io.jl:523 [inlined]
 [8] write(::Base.TTY, ::UInt8) at ./stream.jl:973
 [9] write at ./io.jl:576 [inlined]
 [10] print(::Base.TTY, ::Char) at ./char.jl:229
 [11] print(::Char) at ./coreio.jl:3
 [12] top-level scope at ./REPL[1]:2

Here is my version info:

julia> versioninfo()
Julia Version 1.2.0-rc3.0
Commit f18655ed3c (2019-08-12 20:32 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.1 (ORCJIT, haswell)

I could not reproduce on v1.1.1:

julia> versioninfo()
Julia Version 1.1.1
Commit 55e36cc308 (2019-05-16 04:10 UTC)
Platform Info:
  OS: Linux (x86_64-pc-linux-gnu)
  CPU: Intel(R) Core(TM) i7-4770 CPU @ 3.40GHz
  WORD_SIZE: 64
  LIBM: libopenlibm
  LLVM: libLLVM-6.0.1 (ORCJIT, haswell)

[JeffBezanson]

I'm just grateful that (1) it actually interrupts the loop and (2) doesn't crash :)