Auto merge of #55617 - oli-obk:stacker, r=nagisa,oli-obk

Prevent compiler stack overflow for deeply recursive code

I was unable to write a test that

1. runs in under 1s
2. overflows on my machine without this patch

The following reproduces the issue, but I don't think it's sensible to include a test that takes 30s to compile. We can now easily squash newly appearing overflows by the strategic insertion of calls to `ensure_sufficient_stack`.

```rust
// compile-pass

#![recursion_limit="1000000"]

macro_rules! chain {
    (EE $e:expr) => {$e.sin()};
    (RECURSE $i:ident $e:expr) => {chain!($i chain!($i chain!($i chain!($i $e))))};
    (Z $e:expr) => {chain!(RECURSE EE $e)};
    (Y $e:expr) => {chain!(RECURSE Z $e)};
    (X $e:expr) => {chain!(RECURSE Y $e)};
    (A $e:expr) => {chain!(RECURSE X $e)};
    (B $e:expr) => {chain!(RECURSE A $e)};
    (C $e:expr) => {chain!(RECURSE B $e)};
    // causes overflow on x86_64 linux
    // less than 1 second until overflow on test machine
    // after overflow has been fixed, takes 30s to compile :/
    (D $e:expr) => {chain!(RECURSE C $e)};
    (E $e:expr) => {chain!(RECURSE D $e)};
    (F $e:expr) => {chain!(RECURSE E $e)};
    // more than 10 seconds
    (G $e:expr) => {chain!(RECURSE F $e)};
    (H $e:expr) => {chain!(RECURSE G $e)};
    (I $e:expr) => {chain!(RECURSE H $e)};
    (J $e:expr) => {chain!(RECURSE I $e)};
    (K $e:expr) => {chain!(RECURSE J $e)};
    (L $e:expr) => {chain!(RECURSE L $e)};
}

fn main() {
    let x = chain!(D 42.0_f32);
}
```

fixes #55471
fixes #41884
fixes #40161
fixes #34844
fixes #32594

cc @alexcrichton @rust-lang/compiler

I looked at all code that checks the recursion limit and inserted stack growth calls where appropriate.

1 files changed, 1 insertions, 8 deletions

diff --git a/src/librustc_interface/util.rs b/src/librustc_interface/util.rs
index c5a4d28d151..0797ab33827 100644
--- a/src/librustc_interface/util.rs
+++ b/src/librustc_interface/util.rs
@@ -81,14 +81,7 @@ pub fn create_session(
     (Lrc::new(sess), Lrc::new(codegen_backend), source_map)
 }
 
-// Temporarily have stack size set to 32MB to deal with various crates with long method
-// chains or deep syntax trees, except when on Haiku.
-// FIXME(oli-obk): get https://github.com/rust-lang/rust/pull/55617 the finish line
-#[cfg(not(target_os = "haiku"))]
-const STACK_SIZE: usize = 32 * 1024 * 1024;
-
-#[cfg(target_os = "haiku")]
-const STACK_SIZE: usize = 16 * 1024 * 1024;
+const STACK_SIZE: usize = 8 * 1024 * 1024;
 
 fn get_stack_size() -> Option<usize> {
     // FIXME: Hacks on hacks. If the env is trying to override the stack size