Abort at program exist with RUST_LOG=debug and SIngleThreaded task

[MicahChalmer]

If you set RUST_LOG=debug and run a program that spawns a task in SingleThreaded mode, the program will abort at the end with a lovecraft quote and the message "thread-local pointer is null. bogus!" This program is sufficient to see the crash:

use std::task;

fn main() {
    let mut t = task::task();
    t.sched_mode(task::SingleThreaded);
    t.spawn(|| ());
}

The output, if run with RUST_LOG=debug:

spawn calling run_task
boostrapping a 1:1 scheduler


The ocean ate the last of the land and poured into the smoking gulf, thereby
giving up all it had ever conquered. From the new-flooded lands it flowed
again, uncovering death and decay; and from its ancient and immemorial bed it
trickled loathsomely, uncovering nighted secrets of the years when Time was
young and the gods unborn. Above the waves rose weedy remembered spires. The
moon laid pale lilies of light on dead London, and Paris stood up from its damp
grave to be sanctified with star-dust. Then rose spires and monoliths that were
weedy but not remembered; terrible spires and monoliths of lands that men never
knew were lands...

fatal runtime error: thread-local pointer is null. bogus!

without RUST_LOG=debug it runs fine.

[alexcrichton]

Hm, this appears to be my fault as part of 8b4423b. Before that commit these components were using rtdebug which uses blocking native I/O instead of libuv I/O. I think that these blocks of code are running too soon for libuv I/O to work, so they should probably just get removed.