Fixes#10302
I really am not sure I'm doing this right, so here goes nothing...
Also testing this isn't easy. I don't have any other *nix boxes besides a Linux one.
Test code:
```rust
use std::thread;
use std::io::timer::sleep;
use std::time::duration::Duration;
fn make_thread<'a>(i: i64) -> thread::JoinGuard<'a, ()>
{
thread::Builder::new().name(format!("MyThread{}", i).to_string()).scoped(move ||
{
println!("Start: {}", i);
sleep(Duration::seconds(i));
println!("End: {}", i);
})
}
fn main()
{
let mut guards = vec![make_thread(3)];
for i in 4i64..16
{
guards.push(make_thread(i));
}
}
```
GDB output on my machine:
```
(gdb) info threads
Id Target Id Frame
15 Thread 0x7fdfbb35f700 (LWP 23575) "MyThread3" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
14 Thread 0x7fdfba7ff700 (LWP 23576) "MyThread4" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
13 Thread 0x7fdfba5fe700 (LWP 23577) "MyThread5" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
12 Thread 0x7fdfba3fd700 (LWP 23578) "MyThread6" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
11 Thread 0x7fdfb8dfe700 (LWP 23580) "MyThread4" 0x00007fdfbb746193 in select () from /usr/lib/libc.so.6
10 Thread 0x7fdfb8fff700 (LWP 23579) "MyThread7" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
9 Thread 0x7fdfb8bfd700 (LWP 23581) "MyThread8" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
8 Thread 0x7fdfb3fff700 (LWP 23582) "MyThread9" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
7 Thread 0x7fdfb3dfe700 (LWP 23583) "MyThread10" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
6 Thread 0x7fdfb3bfd700 (LWP 23584) "MyThread11" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
5 Thread 0x7fdfb2bff700 (LWP 23585) "MyThread12" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
4 Thread 0x7fdfb29fe700 (LWP 23586) "MyThread13" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
3 Thread 0x7fdfb27fd700 (LWP 23587) "MyThread14" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
2 Thread 0x7fdfb1bff700 (LWP 23588) "MyThread15" 0x00007fdfbbe35a8d in nanosleep () from /usr/lib/libpthread.so.0
* 1 Thread 0x7fdfbc411800 (LWP 23574) "threads" 0x00007fdfbbe2e505 in pthread_join () from /usr/lib/libpthread.so.0
```
(I'm not sure why one of the threads is duplicated, but it does that without my patch too...)
b70ec4d9f0