Illegal instruction in nightly-x86_64-unknown-linux-gnu unchanged - rustc 1.29.0-nightly (866a71325 2018-07-29)

[norru]

Illegal instruction in nightly

2018-07-30T20:46:20.443731114+01:00 INFO rust_oids::app - Resuming simulation from snapshot: "/home/nico/.config/rust-oids/saved_state/20180730_193912.json"
error: XDG_RUNTIME_DIR not set in the environment.
Illegal instruction
nico@lenovo-devuan:~/Projects/itadinanta/rust-oids$ gdb target/release/rust-oids 
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Reading symbols from target/release/rust-oids...done.
(gdb) run
Starting program: /u01/home/nico/Projects/itadinanta/rust-oids/target/release/rust-oids 
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
2018-07-30T20:46:43.747665697+01:00 INFO rust_oids::app - Resuming simulation from snapshot: "/home/nico/.config/rust-oids/saved_state/20180730_193912.json"
error: XDG_RUNTIME_DIR not set in the environment.

Program received signal SIGILL, Illegal instruction.
0x0000555555758d1b in x11_dl::xlib_xcb::Xlib_xcb::open::hcf5d0b06fb3c742a ()
(gdb) stack
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(gdb) bt
#0  0x0000555555758d1b in x11_dl::xlib_xcb::Xlib_xcb::open::hcf5d0b06fb3c742a ()
#1  0x00005555556f9b20 in winit::platform::platform::x11::xdisplay::XConnection::new::hd8037cc51043bb68 ()
#2  0x00005555556f14bc in std::sync::once::Once::call_once::_$u7b$$u7b$closure$u7d$$u7d$::h3db9c6506b2778f4 ()
#3  0x00005555557f70e1 in std::sync::once::Once::call_inner::h19d8fb8519a6ca98 () at libstd/sync/once.rs:349
#4  0x0000555555702945 in winit::platform::platform::EventsLoop::new::h96a6247628a19d25 ()
#5  0x00005555556fe0b8 in winit::EventsLoop::new::h494bdedfa0de9eda ()
#6  0x000055555565b8c0 in rust_oids::app::main::main_loop::h05b6ab6851b78251 ()
#7  0x00005555555f3645 in rust_oids::app::run::h9bd1da782e5bcfa7 ()
#8  0x00005555556390f6 in rust_oids::main::h93ddf1c0aa5bdd7c ()
#9  0x0000555555625c23 in std::rt::lang_start::_$u7b$$u7b$closure$u7d$$u7d$::h8a490e39f0d9316a ()
#10 0x00005555557e4ff3 in std::rt::lang_start_internal::_$u7b$$u7b$closure$u7d$$u7d$::he46bbe21d122334d () at libstd/rt.rs:59
#11 std::panicking::try::do_call::h8ed5eafe3e94e158 () at libstd/panicking.rs:310
#12 0x000055555580492a in __rust_maybe_catch_panic () at libpanic_unwind/lib.rs:105
#13 0x00005555557e7a16 in std::panicking::try::hb8f13a044e539797 () at libstd/panicking.rs:289
#14 std::panic::catch_unwind::h09594af9f6e0fec4 () at libstd/panic.rs:392
#15 std::rt::lang_start_internal::ha4a5edbf3a495792 () at libstd/rt.rs:58
#16 0x0000555555639c04 in main ()

[nagisa]

The code in question is this.

[sfackler]

That code is unsound. Function pointers in Rust are non-null, but that code creates a mem::zeroed struct that contains function pointers.

[pnkfelix]

visited for triage. Under the assumption that the shown code is indeed the cause of the illegal instruction, closing this as non-actionable on our part.