Panic in Vector of length > 4099 #67
Description
See issue #55, but I am opening a new issue because I do not have the permissions to reopen the previous issue.
extern crate im_rc;
fn main() {
let mut l = im_rc::Vector::singleton(0);
for _ in 0..4099 {
let mut tmp = im_rc::Vector::singleton(0);
tmp.append(l);
l = tmp;
}
let len = l.len();
l.slice(1..len);
}
Note this is the exact same program, but with a slightly higher number of iterations in the loop. The actual program I'm debugging iterates up to 7621 iterations, so you should probably continue to test up to substantially higher N this time.
The new backtrace:
thread 'hook_list::tests::test_long_list' panicked at 'called `Option::unwrap()` on a `None` value', libcore/option.rs:345:21
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
stack backtrace:
0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
at libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
1: std::sys_common::backtrace::print
at libstd/sys_common/backtrace.rs:71
at libstd/sys_common/backtrace.rs:59
2: std::panicking::default_hook::{{closure}}
at libstd/panicking.rs:211
3: std::panicking::default_hook
at libstd/panicking.rs:221
4: std::panicking::rust_panic_with_hook
at libstd/panicking.rs:511
5: std::panicking::continue_panic_fmt
at libstd/panicking.rs:426
6: rust_begin_unwind
at libstd/panicking.rs:337
7: core::panicking::panic_fmt
at libcore/panicking.rs:92
8: core::panicking::panic
at libcore/panicking.rs:53
9: <core::option::Option<T>>::unwrap
at /checkout/src/libcore/macros.rs:20
10: <im_rc::nodes::rrb::Node<A>>::len
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/nodes/rrb.rs:343
11: <im_rc::nodes::rrb::Node<A>>::split
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/nodes/rrb.rs:722
12: <im_rc::vector::Vector<A>>::split_off
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/mod.rs:1043
13: <im_rc::vector::Vector<A>>::slice
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/mod.rs:1157
14: datastructures::hook_list::tests::test_long_list
at src/hook_list.rs:521
15: datastructures::__test::TESTS::{{closure}}
at src/hook_list.rs:513
16: core::ops::function::FnOnce::call_once
at /checkout/src/libcore/ops/function.rs:223
17: <F as alloc::boxed::FnBox<A>>::call_box
at libtest/lib.rs:1451
at /checkout/src/libcore/ops/function.rs:223
at /checkout/src/liballoc/boxed.rs:640
18: __rust_maybe_catch_panic
at libpanic_unwind/lib.rs:105
I also got another backtrace with the same error message that is probably related, but I haven't had a chance to construct a minimal example yet; I include it here in the hopes that it might give you some insight or that it might lead your attention to another possible location where a bug of this type might be occurring:
#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#1 0x00007ffff599d801 in __GI_abort () at abort.c:79
#2 0x00000000009acaf6 in panic_abort::__rust_start_panic::abort () at libpanic_abort/lib.rs:61
#3 0x00000000009acae6 in __rust_start_panic () at libpanic_abort/lib.rs:56
#4 0x0000000000966a98 in rust_panic () at libstd/panicking.rs:559
#5 0x00000000009669b4 in std::panicking::rust_panic_with_hook () at libstd/panicking.rs:531
#6 0x00000000009666ba in std::panicking::continue_panic_fmt () at libstd/panicking.rs:426
#7 0x00000000009663d6 in rust_begin_unwind () at libstd/panicking.rs:337
#8 0x000000000095360c in core::panicking::panic_fmt () at libcore/panicking.rs:92
#9 0x000000000095353b in core::panicking::panic () at libcore/panicking.rs:53
#10 0x000000000090a4c9 in <core::option::Option<T>>::unwrap (self=...) at /checkout/src/libcore/macros.rs:20
#11 0x00000000008fb8af in <im_rc::nodes::rrb::Node<A>>::lookup_chunk (self=0x7fff0e604658, level=1, base=0, index=3200)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/nodes/rrb.rs:476
#12 0x00000000008fb9e8 in <im_rc::nodes::rrb::Node<A>>::lookup_chunk (self=0x7fff0e603b28, level=2, base=0, index=3200)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/nodes/rrb.rs:481
#13 0x0000000000928ab3 in <im_rc::vector::focus::TreeFocus<A>>::set_focus (self=0x7fffffff70b8, index=3218)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/focus.rs:365
#14 0x0000000000928446 in <im_rc::vector::focus::TreeFocus<A>>::get (self=0x7fffffff70b8, index=3218)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/focus.rs:386
#15 0x0000000000928c0d in <im_rc::vector::focus::Focus<'a, A>>::get (self=0x7fffffff70b0, index=3218)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/focus.rs:129
#16 0x00000000008f1f78 in <im_rc::vector::Iter<'a, A> as core::iter::iterator::Iterator>::next (self=0x7fffffff70b0)
at /home/dwightguth/.cargo/registry/src/github.com-1ecc6299db9ec823/im-rc-12.3.0/./src/vector/mod.rs:1858