GcUnsafe warnings.nim

# Warning: not GC-safe: 't' [GcUnsafe] -- generated when using objects (t here) that have closures as member.
# Compile with --threads:on

type
  TTTTT = object
    onCalled: proc(i: int) {.closure.}

var
  t: TTTTT                                 # <== This is GCed, so the whole 't' instance is not gcsafe
  x = 0

t.onCalled = proc(i: int) {.closure.} =    # <== warning here
  echo "Dummy closure proc, " & $i

t.onCalled(x)                              # <== warning here