out of memory

[matthiaskrgr]

I tried this code:
I found this code would make rustc eat more than 20 gb of memory until OOM killer stopped it

fn T<T>(x: &T::<T::<T::<T::<T::<T::<T::<x, HT::U<T::<T::<x, T::<T::<T::<T::<T::<T::<T::<T::<x, T::<T, T>>T::<x, HT::U<T::<T::<x, T::<T::<TT::<T::(<T::<T)::<x, )T>>, T>>, T::<T:T, T>>>>>, T>>, T>>>, T::<x, T::<T::<T::<>>, T

I expected to see this happen: explanation

Instead, this happened: explosion

Meta

rustc --version --verbose:

rustc 1.74.0-nightly (59a829484 2023-08-30)
binary: rustc
commit-hash: 59a8294849358a878a72358aa6d5fe5b9d312867
commit-date: 2023-08-30
host: x86_64-unknown-linux-gnu
release: 1.74.0-nightly
LLVM version: 17.0.0

[SteveLauC]

I copied this line of code into Clion, and the whole OS immediately got stuck, then OOM, and all my apps were killed :>

[matthiaskrgr]

Hm this is actually a regression from 1.68 to 1.69 (not very nice!) 🤔 1.68 will show syntax error within <1s

[lqd]

Bisects to nightly-2023-01-29.

[apiraino]

WG-prioritization assigning priority (Zulip discussion).

@rustbot label -I-prioritize +P-medium