Out of stack error with struct containing an Option of itself

[dotdash]

This code

struct Foo { v: Option<Foo> }

fn main() {
  Foo { v: None };
}

causes the compiler to run out of stack.

rust: task 14114e0 ran out of stack
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4f)[0x7fde632ba52f]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_ZN9rust_task9new_stackEm+0x158)[0x7fde632ba778]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(+0x299f1)[0x7fde632ca9f1]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(upcall_new_stack+0x28c)[0x7fde632bd34c]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e1a)[0x7fde65499e1a]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x38ae1b)[0x7fde64f6ae1b]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty14__extensions__10meth_4004910iter_bytes17_6d4d402c59155c393_06E+0x169)[0x7fde64f69a69]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x38adaa)[0x7fde64f6adaa]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty14__extensions__10meth_3814010iter_bytes17_6d4d402c59155c393_06E+0x9ee)[0x7fde64f3265e]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty14__extensions__10meth_3813510iter_bytes17_6d4d402c59155c393_06E+0x88)[0x7fde64f31bc8]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x370b4a)[0x7fde64f50b4a]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x36fd74)[0x7fde64f4fd74]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x36fc39)[0x7fde64f4fc39]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty7mk_enum16_b7fa25d463c35113_06E+0x1f0)[0x7fde64f546c0]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty19fold_regions_and_ty17_5df880af9eb9e9a43_06E+0x16e)[0x7fde64f581fe]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x37ae66)[0x7fde64f5ae66]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty8fold_sig17_2ff1c49afce455833_06E+0x197)[0x7fde64f579c7]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty19fold_regions_and_ty17_5df880af9eb9e9a43_06E+0x32b)[0x7fde64f583bb]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x37ae66)[0x7fde64f5ae66]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty5subst16_7b72eb1b651f4b73_06E+0x381)[0x7fde64db5471]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x39fd15)[0x7fde64f7fd15]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x2b8c21)[0x7fde64e98c21]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN6middle2ty20substd_enum_variants17_47b8d6e5411762f93_06E+0xa6)[0x7fde64ee52c6]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384b54)[0x7fde64f64b54]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384d72)[0x7fde64f64d72]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384bf2)[0x7fde64f64bf2]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384d72)[0x7fde64f64d72]
[... lots of those two omitted ...]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384bf2)[0x7fde64f64bf2]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384d72)[0x7fde64f64d72]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384bf2)[0x7fde64f64bf2]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x384d72)[0x7fde64f64d72]
error: internal compiler error: unexpected failure
note: the compiler hit an unexpected failure path. this is a bug
note: try running with RUST_LOG=rustc=1,::rt::backtrace to get further details and report the results to github.com/mozilla/rust/issues
rust: task failed at 'explicit failure', /home/rustbuild/src/rust-buildbot/slave/snap3-linux/build/src/librustc/rustc.rc:357
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_ZN9rust_task13begin_failureEPKcS1_m+0x4f)[0x7fde632ba52f]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(+0x299f1)[0x7fde632ca9f1]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(upcall_fail+0x1c6)[0x7fde632bccb6]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x1059ab)[0x7fde664e39ab]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x105952)[0x7fde664e3952]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(_ZN3sys12begin_unwind16_701b8ec61f97ead3_06E+0x71)[0x7fde6642b441]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/libcore-c3ca5d77d81b46c1-0.6.so(+0x14e214)[0x7fde6652c214]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN7monitor17_ab3b5d4d4b9efdb63_06E+0x1577)[0x7fde6548d947]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(+0x8b9e84)[0x7fde65499e84]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustc-c84825241471686d-0.6.so(_ZN4main16_706f4ee7413ae583_06E+0x7e)[0x7fde65499a9e]
/home/doener/src/rust-submit/x86_64-unknown-linux-gnu/stage0/bin/../lib/librustrt.so(_Z18task_start_wrapperP10spawn_args+0x24)[0x7fde632bb534]
rust: domain main @0x14073c0 root task failed

[thestinger]

This happens because the type would be an infinite size, and the compiler is really bad at identifying those cases so it ends up doing infinite recursion.

Closing in favour of the existing #4363.