core dump when receiving message

of file /home/lms/src/deltachat/deltachat-core-rust/target/debug/examples/repl.
Use `info auto-load python-scripts [REGEXP]' to list them.
(gdb) bt
#0  __strlen_avx2 () at ../sysdeps/x86_64/multiarch/strlen-avx2.S:62
#1  0x000055973cada91a in std::ffi::c_str::CStr::from_ptr () at src/libstd/ffi/c_str.rs:963
#2  0x000055973bab05e7 in deltachat::dc_job::dc_job_do_DC_JOB_MOVE_MSG (context=0x55973dc23650, job=0x7f7aae9d9608) at src/dc_job.rs:493
#3  0x000055973baae12a in deltachat::dc_job::dc_job_perform (context=0x55973dc23650, thread=100, probe_network=0) at src/dc_job.rs:150
#4  0x000055973baad67a in deltachat::dc_job::dc_perform_imap_jobs (context=0x55973dc23650) at src/dc_job.rs:62
#5  0x000055973ba40ded in repl::start_threads::{{closure}} () at examples/repl/main.rs:192
#6  0x000055973ba2c533 in std::sys_common::backtrace::__rust_begin_short_backtrace (f=...) at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/sys_common/backtrace.rs:136
#7  0x000055973ba3f03e in std::thread::Builder::spawn_unchecked::{{closure}}::{{closure}} () at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/thread/mod.rs:469
#8  0x000055973ba30231 in <std::panic::AssertUnwindSafe<F> as core::ops::function::FnOnce<()>>::call_once (self=..., _args=()) at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/panic.rs:309
#9  0x000055973ba41dc5 in std::panicking::try::do_call (data=0x7f7aae9d9968 "06\302=\227U") at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/panicking.rs:293
#10 0x000055973caed8aa in __rust_maybe_catch_panic () at src/libpanic_unwind/lib.rs:85
#11 0x000055973ba419be in std::panicking::try (f=...) at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/panicking.rs:272
#12 0x000055973ba30253 in std::panic::catch_unwind (f=...) at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/panic.rs:388
#13 0x000055973ba3e846 in std::thread::Builder::spawn_unchecked::{{closure}} () at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libstd/thread/mod.rs:468
#14 0x000055973ba30523 in core::ops::function::FnOnce::call_once{{vtable-shim}} () at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/libcore/ops/function.rs:231
#15 0x000055973cad7f6f in call_once<(),FnOnce<()>> () at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/liballoc/boxed.rs:704
#16 0x000055973caecc10 in call_once<(),alloc::boxed::Box<FnOnce<()>>> () at /rustc/5d20ff4d2718c820632b38c1e49d4de648a9810b/src/liballoc/boxed.rs:704
#17 start_thread () at src/libstd/sys_common/thread.rs:13
#18 thread_start () at src/libstd/sys/unix/thread.rs:79
#19 0x00007f7aaed7d164 in start_thread (arg=<optimized out>) at pthread_create.c:486
#20 0x00007f7aaec89def in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95