IM writes:
For purposes of debugging, I'm using writeln() to print stuff out from tasks running concurrently on many threads. At some point it crashes with the following stack trace:
Thread 4 received signal SIGUSR1, User defined signal 1.
[Switching to Thread 0x7ffff5ec2700 (LWP 19267)]
__lll_lock_wait_private () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95
95 ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S: No such file or directory.
(gdb) bt
#0 __lll_lock_wait_private () at ../sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:95
#1 0x00007ffff7bcb2d5 in __flockfile (stream=0x7ffff728b780 <_IO_stdfile_1_lock>) at ../sysdeps/pthread/flockfile.c:28
#2 0x000000000045f5b0 in _D3std5stdio4File17LockingTextWriter6__ctorMFNcNeKSQBxQBwQBtZSQCiQChQCeQCc ()
#3 0x000000000045f670 in _D3std5stdio4File17lockingTextWriterMFNfZSQBoQBnQBk17LockingTextWriter ()
#4 0x000000000044a1e0 in _D3std5stdio4File__T5writeTAyaTyiTaZQqMFNfQpyiaZv (this=..., _param_2=10 '\n', _param_1=12, _param_0=...)
at /usr/include/dmd/phobos/std/stdio.d:1399
Note that I didn't add any synchronizations around the writeln() calls, should I? I assume the implementation *should* synchronize access to std_out, no?