Merge branch 'arm-dynlink' into 'master'

Fix missing symbols for ARM dynamic linking

See merge request redox-os/relibc!763

ld_so/ld_script/aarch64-unknown-redox.ld

@@ -110,13 +110,13 @@ SECTIONS
     KEEP (*(.preinit_array))
     PROVIDE_HIDDEN (__preinit_array_end = .);
   }
-  /* .init_array    :
+  .init_array    :
   {
     PROVIDE_HIDDEN (__init_array_start = .);
     KEEP (*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
     KEEP (*(.init_array EXCLUDE_FILE (*crtbegin.o *crtbegin?.o *crtend.o *crtend?.o ) .ctors))
     PROVIDE_HIDDEN (__init_array_end = .);
-  } */
+  }
   .fini_array    :
   {
     PROVIDE_HIDDEN (__fini_array_start = .);
@@ -248,9 +248,8 @@ SECTIONS
      * ld.so will be moved out of relibc. So, till that time, we have to discard any sections
      * that may reference use thread local storage.
      *
-     * .init_array also depends on TLS and is discarded as we don't need it.
+     * .init_array need to be not discarded unlike x86_64 linker variant
      */
     *(.gnu.linkonce.tb.*) *(.tcommon)
-    *(.init_array)
   }
 }

src/cxa.rs

@@ -1,29 +1,104 @@
-use crate::{platform::types::*, raw_cell::RawCell};
-
-// TODO: Implement cxa_finalize and uncomment this
+use crate::platform::types::*;
+use alloc::vec::Vec;
+use core::{cell::RefCell, ptr};
+use spin::Mutex;
 
 #[derive(Clone, Copy)]
 struct CxaAtExitFunc {
-    //func: extern "C" fn(*mut c_void),
-    //arg: *mut c_void,
-    //dso: *mut c_void,
+    func: extern "C" fn(*mut c_void),
+    arg: usize,
+    dso: usize,
 }
 
-static CXA_ATEXIT_FUNCS: RawCell<[Option<CxaAtExitFunc>; 32]> = RawCell::new([None; 32]);
+#[derive(Clone, Copy)]
+struct CxaThreadAtExitFunc {
+    func: extern "C" fn(*mut c_void),
+    obj: *mut c_void,
+    dso: *mut c_void,
+}
+
+static CXA_ATEXIT_FUNCS: Mutex<Vec<Option<CxaAtExitFunc>>> = Mutex::new(Vec::new());
+#[thread_local]
+static DTORS: RefCell<Vec<CxaThreadAtExitFunc>> = RefCell::new(Vec::new());
 
 #[unsafe(no_mangle)]
 pub unsafe extern "C" fn __cxa_atexit(
-    func_opt: Option<extern "C" fn(*mut c_void)>,
+    func: Option<extern "C" fn(*mut c_void)>,
     arg: *mut c_void,
     dso: *mut c_void,
 ) -> c_int {
-    for i in 0..CXA_ATEXIT_FUNCS.unsafe_ref().len() {
-        if CXA_ATEXIT_FUNCS.unsafe_ref()[i].is_none() {
-            CXA_ATEXIT_FUNCS.unsafe_mut()[i] =
-                func_opt.map(|func| CxaAtExitFunc {} /*{ func, arg, dso }*/);
+    let Some(func) = func else {
+        return 0;
+    };
+
+    let entry = CxaAtExitFunc {
+        func,
+        arg: arg as usize,
+        dso: dso as usize,
+    };
+
+    let mut funcs = CXA_ATEXIT_FUNCS.lock();
+
+    for slot in funcs.iter_mut() {
+        if slot.is_none() {
+            *slot = Some(entry);
             return 0;
         }
     }
 
-    -1
+    // No empty slots
+    funcs.push(Some(entry));
+    0
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn __cxa_finalize(dso: *mut c_void) {
+    let mut funcs = CXA_ATEXIT_FUNCS.lock();
+
+    let dso_usize = dso as usize;
+
+    for slot in funcs.iter_mut().rev() {
+        if let Some(entry) = slot.as_ref() {
+            if dso.is_null() || entry.dso == dso_usize {
+                if let Some(entry_to_run) = slot.take() {
+                    (entry_to_run.func)(entry_to_run.arg as *mut c_void);
+                }
+            }
+        }
+    }
+
+    // clean up remaining list
+    if dso.is_null() {
+        funcs.clear();
+    } else {
+        funcs.retain(|opt| opt.is_some());
+    }
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn __cxa_thread_atexit_impl(
+    func: extern "C" fn(*mut c_void),
+    obj: *mut c_void,
+    dso: *mut c_void,
+) {
+    let entry = CxaThreadAtExitFunc { func, obj, dso };
+    DTORS.borrow_mut().push(entry);
+}
+
+// called internally
+pub unsafe fn __cxa_thread_finalize() {
+    let mut dtors = DTORS.borrow_mut();
+    while let Some(entry) = dtors.pop() {
+        (entry.func)(entry.obj);
+    }
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn _ITM_deregisterTMCloneTable(_ptr: *mut c_void) {
+    // No-op
+}
+
+#[unsafe(no_mangle)]
+pub unsafe extern "C" fn _ITM_registerTMCloneTable(_ptr: *mut c_void, _len: usize) {
+    // No-op
 }

src/header/pthread/mod.rs

@@ -302,6 +302,8 @@ pub unsafe extern "C" fn __relibc_internal_pthread_cleanup_pop(execute: c_int) {
 }
 
 pub(crate) unsafe fn run_destructor_stack() {
+    unsafe { crate::cxa::__cxa_thread_finalize() };
+
     let mut ptr = CLEANUP_LL_HEAD.get();
 
     while !ptr.is_null() {