WIP: Revert PR changes to see if that fixes the CI

Author: zebreus

lib/compiler/src/engine/unwind/systemv.rs

@@ -3,11 +3,7 @@
 
 //! Module for System V ABI unwind registry.
 
-use core::sync::atomic::{
-    AtomicBool, AtomicUsize,
-    Ordering::{self, Relaxed},
-};
-use std::sync::Once;
+use core::sync::atomic::{AtomicUsize, Ordering::Relaxed};
 
 use crate::types::unwind::CompiledFunctionUnwindInfoReference;
 
@@ -143,12 +139,6 @@ impl UnwindRegistry {
 
     #[allow(clippy::cast_ptr_alignment)]
     unsafe fn register_frames(&mut self, eh_frame: &[u8]) {
-        // Register atexit handler that will tell us if exit has been called.
-        static INIT: Once = Once::new();
-        INIT.call_once(|| unsafe {
-            libc::atexit(atexit_handler);
-        });
-
         #[cfg(all(target_os = "macos", target_arch = "aarch64"))]
         {
             // Special call for macOS on aarch64 to register the `.eh_frame` section.
@@ -247,12 +237,6 @@ impl UnwindRegistry {
     }
 }
 
-static EXIT_CALLED: AtomicBool = AtomicBool::new(false);
-
-extern "C" fn atexit_handler() {
-    EXIT_CALLED.store(true, Ordering::SeqCst);
-}
-
 impl Drop for UnwindRegistry {
     fn drop(&mut self) {
         if self.published {
@@ -274,12 +258,6 @@ impl Drop for UnwindRegistry {
 
                     #[cfg(not(all(target_os = "macos", target_arch = "aarch64")))]
                     {
-                        // We don't want to deregister frames in UnwindRegistry::Drop as that could be called during
-                        // program shutdown and can collide with release_registered_frames and lead to
-                        // crashes.
-                        if EXIT_CALLED.load(Ordering::SeqCst) {
-                            return;
-                        }
                         __deregister_frame(*registration as *const _);
                     }
                 }