panic in Local.ymd_opt() on old dates for target i686-pc-windows-msvc

[galich]

This code:

[dependencies]
chrono = "0.4.10"

use chrono::{Local, TimeZone};

fn main() {
    println!("{:?}", Local.ymd_opt(1820, 1, 1));
}

results in panic inside time crate:

❯ cargo r
   Compiling ymdpanic v0.1.0 (C:\code\ymdpanic)
    Finished dev [unoptimized + debuginfo] target(s) in 0.44s
     Running `target\i686-pc-windows-msvc\debug\ymdpanic.exe`
thread 'main' panicked at 'attempt to subtract with overflow', C:\...\time-0.1.42\src\sys.rs:786:22
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
error: process didn't exit successfully: `target\i686-pc-windows-msvc\debug\ymdpanic.exe` (exit code: 101)

[quodlibetor]

Could you re-run with RUST_BACKTRACE=1 and paste the backtrace? I don't have any way of running on i686-pc-windows-msvc

[galich]

sure, here it is:

    Finished dev [unoptimized + debuginfo] target(s) in 0.05s
     Running `target\i686-pc-windows-msvc\debug\ymdpanic.exe`
thread 'main' panicked at 'attempt to subtract with overflow', C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\time-0.1.42\src\sys.rs:786:22
stack backtrace:
   0: core::fmt::write
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libcore\fmt\mod.rs:1028
   1: std::io::Write::write_fmt<std::sys::windows::stdio::Stderr>
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\io\mod.rs:1412
   2: std::sys_common::backtrace::_print
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\sys_common\backtrace.rs:65
   3: std::sys_common::backtrace::print
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\sys_common\backtrace.rs:50
   4: std::panicking::default_hook::{{closure}}
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:188
   5: std::panicking::default_hook
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:205
   6: std::panicking::rust_panic_with_hook
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:464
   7: std::panicking::continue_panic_fmt
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:373
   8: std::panicking::rust_begin_panic
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:302
   9: core::panicking::panic_fmt
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libcore\panicking.rs:139
  10: core::panicking::panic
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libcore\panicking.rs:70
  11: time::sys::inner::system_time_to_tm
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\time-0.1.42\src\sys.rs:786
  12: time::sys::inner::time_to_local_tm
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\time-0.1.42\src\sys.rs:828
  13: time::at
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\time-0.1.42\src\lib.rs:419
  14: chrono::offset::local::{{impl}}::from_local_datetime
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\chrono-0.4.10\src\offset\local.rs:142
  15: chrono::offset::local::{{impl}}::from_local_date
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\chrono-0.4.10\src\offset\local.rs:134
  16: chrono::offset::TimeZone::ymd_opt<chrono::offset::local::Local>
             at C:\Users\serg\.cargo\registry\src\github.com-1ecc6299db9ec823\chrono-0.4.10\src\offset\mod.rs:235
  17: ymdpanic::main
             at .\src\main.rs:4
  18: std::rt::lang_start_internal::{{closure}}
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\rt.rs:48
  19: std::panicking::try::do_call<closure-0,i32>
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:287
  20: panic_unwind::__rust_maybe_catch_panic
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libpanic_unwind\lib.rs:78
  21: std::panicking::try
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panicking.rs:265
  22: std::panic::catch_unwind
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\panic.rs:396
  23: std::rt::lang_start_internal
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\/src\libstd\rt.rs:47
  24: std::rt::lang_start<()>
             at /rustc/73528e339aae0f17a15ffa49a8ac608f50c6cf14\src\libstd\rt.rs:61
  25: main
  26: BaseThreadInitThunk
  27: RtlGetAppContainerNamedObjectPath
  28: RtlGetAppContainerNamedObjectPath
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
error: process didn't exit successfully: `target\i686-pc-windows-msvc\debug\ymdpanic.exe` (exit code: 101)```

[galich]

FYI i've hacked this by changing this

        tm.tm_mon = (sys.wMonth - 1) as i32;
        tm.tm_year = (sys.wYear - 1900) as i32;

to this

        tm.tm_mon = (sys.wMonth as i32 - 1) as i32;
        tm.tm_year = (sys.wYear as i32 - 1900) as i32;

in sys.rs fn system_time_to_tm()

[quodlibetor]

Ah, yeah that's too bad. I think this is enough motivation for me to move ahead with #286, which I've been meaning to do for awhile but have had some reservations.

[galich]

time crate has been updated lately with less panics, perhaps try and update dependency on it in chrono?

[quodlibetor]

Unfortunately the newest time crate relies on the absolute newest rust release, which breaks chronos backwards-compatibility policy, and the time 0.2 api is vastly different than 0.1.

[pitdicker]

This particular issue was fixed in #992. We still panic on years prior to 1601 however.

Because there are other open issues about that case I am going to close this one. See #651, #977 and #1150.