std: xous: take eh_frame address from main args

The main() function takes an argument that contains the eh_frame address. Implement `unwinding` support by looking for unwinding data at this address. Signed-off-by: Sean Cross <[email protected]>
rust-lang · Dec 6, 2023 · a6b8de6 · a6b8de6
1 parent 2a533df
commit a6b8de6
Showing 1 changed file with 28 additions and 1 deletion.
diff --git a/library/std/src/sys/xous/os.rs b/library/std/src/sys/xous/os.rs
@@ -7,6 7,28 @@ use crate::marker::PhantomData;
 use crate::os::xous::ffi::Error as XousError;
 use crate::path::{self, PathBuf};
 
 #[cfg(not(test))]
 #[cfg(feature = "panic_unwind")]
 mod eh_unwinding {
  pub(crate) struct EhFrameFinder(usize /* eh_frame */);
  pub(crate) static mut EH_FRAME_SETTINGS: EhFrameFinder = EhFrameFinder(0);
  impl EhFrameFinder {
  pub(crate) unsafe fn init(&mut self, eh_frame: usize) {
  unsafe {
  EH_FRAME_SETTINGS.0 = eh_frame;
  }
  }
  }
  unsafe impl unwind::EhFrameFinder for EhFrameFinder {
  fn find(&self, _pc: usize) -> Option<unwind::FrameInfo> {
  Some(unwind::FrameInfo {
  text_base: None,
  kind: unwind::FrameInfoKind::EhFrame(self.0),
  })
  }
  }
 }
 
 #[cfg(not(test))]
 mod c_compat {
  use crate::os::xous::ffi::exit;
@@ -20,7 42,12 @@ mod c_compat {
  }
 
  #[no_mangle]
- pub extern "C" fn _start() {
  pub extern "C" fn _start(eh_frame: usize) {
  #[cfg(feature = "panic_unwind")]
  unsafe {
  super::eh_unwinding::EH_FRAME_SETTINGS.init(eh_frame);
  unwind::set_custom_eh_frame_finder(&super::eh_unwinding::EH_FRAME_SETTINGS).ok();
  }
  exit(unsafe { main() });
  }