logging macros and writeln!() crash if stderr is redirected to /dev/null

[dwrensha]

The following occurs for me on Mac OSX 10.9.

// child.rs
fn main() {
    for _ in range::<uint>(0, 1000) {
        error!("hello?");
    }
}

// parent.rs
fn main () {
    use std::io::process;

    let config = process::ProcessConfig {
        program : "./child",
        args : [],
        env : None,
        cwd : None,
        io : []
    };

    match process::Process::new(config) {
        Some(ref mut p) => println!("{}", p.wait()),
        None => println("failed to start child")
    }
}

When I run ./parent, I expect the output to be "exit code: 0". Instead, I see an error signal, and not always the same one:

$ ./parent
signal: 6
$ ./parent
signal: 4
$ ./parent
signal: 6
$ ./parent
signal: 6
$ ./parent
signal: 10

[dwrensha]

I see the same behavior if instead I explicitly set the descriptors to Ignored:

...
        io : [process::Ignored, process::Ignored, process::Ignored]
...

[alexcrichton]

What is the expected behavior? This appears to all be working as-intended to me. You have instructed the child to print something, but you have not provided a method of it to print anything, and it's aborting as a result.

It could be a bug that it's aborting incorrectly, but that seems separate from this issue.

[dwrensha]

I expect the child to exit normally.

I discovered that I actually don't need the parent process in order to see the unexpected behavior.

$ ./child 2> /dev/null
Abort trap: 6

Here are some of gdb stack traces I see when the crash occurs:

program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x0000000000000080
[Switching to process 55750 thread 0x271f]
uv__stream_osx_select (arg=0x100d15bd0) at ../../../src/libuv/src/unix/stream.c:157
157   if (fd > s->int_fd)
(gdb) bt
#0  uv__stream_osx_select (arg=0x100d15bd0) at ../../../src/libuv/src/unix/stream.c:157
#1  0x0000000100699b49 in uv__thread_start (arg=<value temporarily unavailable, due to optimizations>) at ../../../src/libuv/src/uv-common.c:274
#2  0x00007fff8fdf9772 in _pthread_start ()
#3  0x00007fff8fde61a1 in thread_start ()

Program received signal SIGABRT, Aborted.
[Switching to process 55754 thread 0x1203]
0x00007fff85b97212 in __pthread_kill ()
(gdb) bt
#0  0x00007fff85b97212 in __pthread_kill ()
#1  0x00007fff8fdfab24 in pthread_kill ()
#2  0x00007fff8fe3ef61 in abort ()
#3  0x0000000100007835 in rt::util::abort::h78af1956eb5e49das::v0.9$x2dpre ()
#4  0x00000001006472b3 in rt::task::begin_unwind::hd550344a74825a7av::v0.9$x2dpre ()
#5  0x0000000100683915 in uvio::HomingIO::fire_homing_missile::h275a15cd89566c45a7::v0.9$x2dpre ()
#6  0x0000000100671181 in file::Drop$FileWatcher::drop::h243d5422d728745Mgap::v0.9$x2dpre ()
#7  0x00000001006710cd in file..FileWatcher::glue_drop::hb83953d6ca359e89ao ()
#8  0x000000010067106d in _$UP$file..FileWatcher::glue_free::hb4f5f58975dc6e74ak ()
#9  0x0000000100039ffb in logging::log::hd2877e3741c67e5aw::v0.9$x2dpre ()
#10 0x0000000100001d03 in main::anon::expr_fn::ap ()
#11 0x00000001000018c7 in main::hada226789343cd84ah::v0.0 ()
#12 0x00000001000d7755 in rt::task::__extensions__::build_start_wrapper::anon::anon::expr_fn::aw ()
#13 0x00000001000d6333 in rt::task::__extensions__::run::anon::expr_fn::a1 ()
#14 0x00000001007402e3 in rust_try (f=<value temporarily unavailable, due to optimizations>, fptr=<value temporarily unavailable, due to optimizations>, env=<value temporarily unavailable, due to optimizations>) at /Users/davidrenshaw/Code/rust/src/rt/rust_cxx_glue.cpp:20
#15 0x00000001000d6243 in rt::task::Unwinder::try::hdc872d3e23884703Sa0::v0.9$x2dpre ()
#16 0x00000001000d4e05 in rt::task::Task::run::he4b13dcb792462759TaY::v0.9$x2dpre ()
#17 0x00000001000d6eda in rt::task::__extensions__::build_start_wrapper::anon::expr_fn::ab ()

Also, the following program shows the same behavior.

// child.rs
fn main() {
    for _ in range::<uint>(0, 1000) {
        writeln!(&mut std::io::stderr() as &mut std::io::Writer, "hello?");
    }
}

[dwrensha]

For comparison, the following program behaves as I think the other versions of "child.rs" ought to.

// child.rs
// exits normally
fn main() {
    let mut w = std::io::stderr();
    for _ in range::<uint>(0, 1000) {
        w.write("hello?\n".as_bytes());
    }
}

However, it reverts back to the bad behavior if I change it to:

// child.rs
// crashes
fn main() {
    for _ in range::<uint>(0, 1000) {
        std::io::stderr().write("hello?\n".as_bytes());
    }
}