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-rw-r--r--library/panic_unwind/src/dwarf/eh.rs192
-rw-r--r--library/panic_unwind/src/dwarf/mod.rs73
-rw-r--r--library/panic_unwind/src/dwarf/tests.rs19
-rw-r--r--library/panic_unwind/src/emcc.rs16
-rw-r--r--library/panic_unwind/src/gcc.rs228
-rw-r--r--library/panic_unwind/src/lib.rs2
-rw-r--r--library/panic_unwind/src/seh.rs10
7 files changed, 0 insertions, 540 deletions
diff --git a/library/panic_unwind/src/dwarf/eh.rs b/library/panic_unwind/src/dwarf/eh.rs
deleted file mode 100644
index 9aa966b5063..00000000000
--- a/library/panic_unwind/src/dwarf/eh.rs
+++ /dev/null
@@ -1,192 +0,0 @@
-//! Parsing of GCC-style Language-Specific Data Area (LSDA)
-//! For details see:
-//!  * <https://refspecs.linuxfoundation.org/LSB_3.0.0/LSB-PDA/LSB-PDA/ehframechpt.html>
-//!  * <https://itanium-cxx-abi.github.io/cxx-abi/exceptions.pdf>
-//!  * <https://www.airs.com/blog/archives/460>
-//!  * <https://www.airs.com/blog/archives/464>
-//!
-//! A reference implementation may be found in the GCC source tree
-//! (`<root>/libgcc/unwind-c.c` as of this writing).
-
-#![allow(non_upper_case_globals)]
-#![allow(unused)]
-
-use crate::dwarf::DwarfReader;
-use core::mem;
-
-pub const DW_EH_PE_omit: u8 = 0xFF;
-pub const DW_EH_PE_absptr: u8 = 0x00;
-
-pub const DW_EH_PE_uleb128: u8 = 0x01;
-pub const DW_EH_PE_udata2: u8 = 0x02;
-pub const DW_EH_PE_udata4: u8 = 0x03;
-pub const DW_EH_PE_udata8: u8 = 0x04;
-pub const DW_EH_PE_sleb128: u8 = 0x09;
-pub const DW_EH_PE_sdata2: u8 = 0x0A;
-pub const DW_EH_PE_sdata4: u8 = 0x0B;
-pub const DW_EH_PE_sdata8: u8 = 0x0C;
-
-pub const DW_EH_PE_pcrel: u8 = 0x10;
-pub const DW_EH_PE_textrel: u8 = 0x20;
-pub const DW_EH_PE_datarel: u8 = 0x30;
-pub const DW_EH_PE_funcrel: u8 = 0x40;
-pub const DW_EH_PE_aligned: u8 = 0x50;
-
-pub const DW_EH_PE_indirect: u8 = 0x80;
-
-#[derive(Copy, Clone)]
-pub struct EHContext<'a> {
-    pub ip: usize,                             // Current instruction pointer
-    pub func_start: usize,                     // Address of the current function
-    pub get_text_start: &'a dyn Fn() -> usize, // Get address of the code section
-    pub get_data_start: &'a dyn Fn() -> usize, // Get address of the data section
-}
-
-pub enum EHAction {
-    None,
-    Cleanup(usize),
-    Catch(usize),
-    Terminate,
-}
-
-pub const USING_SJLJ_EXCEPTIONS: bool = cfg!(all(target_os = "ios", target_arch = "arm"));
-
-pub unsafe fn find_eh_action(lsda: *const u8, context: &EHContext<'_>) -> Result<EHAction, ()> {
-    if lsda.is_null() {
-        return Ok(EHAction::None);
-    }
-
-    let func_start = context.func_start;
-    let mut reader = DwarfReader::new(lsda);
-
-    let start_encoding = reader.read::<u8>();
-    // base address for landing pad offsets
-    let lpad_base = if start_encoding != DW_EH_PE_omit {
-        read_encoded_pointer(&mut reader, context, start_encoding)?
-    } else {
-        func_start
-    };
-
-    let ttype_encoding = reader.read::<u8>();
-    if ttype_encoding != DW_EH_PE_omit {
-        // Rust doesn't analyze exception types, so we don't care about the type table
-        reader.read_uleb128();
-    }
-
-    let call_site_encoding = reader.read::<u8>();
-    let call_site_table_length = reader.read_uleb128();
-    let action_table = reader.ptr.add(call_site_table_length as usize);
-    let ip = context.ip;
-
-    if !USING_SJLJ_EXCEPTIONS {
-        while reader.ptr < action_table {
-            let cs_start = read_encoded_pointer(&mut reader, context, call_site_encoding)?;
-            let cs_len = read_encoded_pointer(&mut reader, context, call_site_encoding)?;
-            let cs_lpad = read_encoded_pointer(&mut reader, context, call_site_encoding)?;
-            let cs_action = reader.read_uleb128();
-            // Callsite table is sorted by cs_start, so if we've passed the ip, we
-            // may stop searching.
-            if ip < func_start + cs_start {
-                break;
-            }
-            if ip < func_start + cs_start + cs_len {
-                if cs_lpad == 0 {
-                    return Ok(EHAction::None);
-                } else {
-                    let lpad = lpad_base + cs_lpad;
-                    return Ok(interpret_cs_action(cs_action, lpad));
-                }
-            }
-        }
-        // Ip is not present in the table.  This should not happen... but it does: issue #35011.
-        // So rather than returning EHAction::Terminate, we do this.
-        Ok(EHAction::None)
-    } else {
-        // SjLj version:
-        // The "IP" is an index into the call-site table, with two exceptions:
-        // -1 means 'no-action', and 0 means 'terminate'.
-        match ip as isize {
-            -1 => return Ok(EHAction::None),
-            0 => return Ok(EHAction::Terminate),
-            _ => (),
-        }
-        let mut idx = ip;
-        loop {
-            let cs_lpad = reader.read_uleb128();
-            let cs_action = reader.read_uleb128();
-            idx -= 1;
-            if idx == 0 {
-                // Can never have null landing pad for sjlj -- that would have
-                // been indicated by a -1 call site index.
-                let lpad = (cs_lpad + 1) as usize;
-                return Ok(interpret_cs_action(cs_action, lpad));
-            }
-        }
-    }
-}
-
-fn interpret_cs_action(cs_action: u64, lpad: usize) -> EHAction {
-    if cs_action == 0 {
-        // If cs_action is 0 then this is a cleanup (Drop::drop). We run these
-        // for both Rust panics and foreign exceptions.
-        EHAction::Cleanup(lpad)
-    } else {
-        // Stop unwinding Rust panics at catch_unwind.
-        EHAction::Catch(lpad)
-    }
-}
-
-#[inline]
-fn round_up(unrounded: usize, align: usize) -> Result<usize, ()> {
-    if align.is_power_of_two() { Ok((unrounded + align - 1) & !(align - 1)) } else { Err(()) }
-}
-
-unsafe fn read_encoded_pointer(
-    reader: &mut DwarfReader,
-    context: &EHContext<'_>,
-    encoding: u8,
-) -> Result<usize, ()> {
-    if encoding == DW_EH_PE_omit {
-        return Err(());
-    }
-
-    // DW_EH_PE_aligned implies it's an absolute pointer value
-    if encoding == DW_EH_PE_aligned {
-        reader.ptr = round_up(reader.ptr as usize, mem::size_of::<usize>())? as *const u8;
-        return Ok(reader.read::<usize>());
-    }
-
-    let mut result = match encoding & 0x0F {
-        DW_EH_PE_absptr => reader.read::<usize>(),
-        DW_EH_PE_uleb128 => reader.read_uleb128() as usize,
-        DW_EH_PE_udata2 => reader.read::<u16>() as usize,
-        DW_EH_PE_udata4 => reader.read::<u32>() as usize,
-        DW_EH_PE_udata8 => reader.read::<u64>() as usize,
-        DW_EH_PE_sleb128 => reader.read_sleb128() as usize,
-        DW_EH_PE_sdata2 => reader.read::<i16>() as usize,
-        DW_EH_PE_sdata4 => reader.read::<i32>() as usize,
-        DW_EH_PE_sdata8 => reader.read::<i64>() as usize,
-        _ => return Err(()),
-    };
-
-    result += match encoding & 0x70 {
-        DW_EH_PE_absptr => 0,
-        // relative to address of the encoded value, despite the name
-        DW_EH_PE_pcrel => reader.ptr as usize,
-        DW_EH_PE_funcrel => {
-            if context.func_start == 0 {
-                return Err(());
-            }
-            context.func_start
-        }
-        DW_EH_PE_textrel => (*context.get_text_start)(),
-        DW_EH_PE_datarel => (*context.get_data_start)(),
-        _ => return Err(()),
-    };
-
-    if encoding & DW_EH_PE_indirect != 0 {
-        result = *(result as *const usize);
-    }
-
-    Ok(result)
-}
diff --git a/library/panic_unwind/src/dwarf/mod.rs b/library/panic_unwind/src/dwarf/mod.rs
deleted file mode 100644
index 652fbe95a14..00000000000
--- a/library/panic_unwind/src/dwarf/mod.rs
+++ /dev/null
@@ -1,73 +0,0 @@
-//! Utilities for parsing DWARF-encoded data streams.
-//! See <http://www.dwarfstd.org>,
-//! DWARF-4 standard, Section 7 - "Data Representation"
-
-// This module is used only by x86_64-pc-windows-gnu for now, but we
-// are compiling it everywhere to avoid regressions.
-#![allow(unused)]
-
-#[cfg(test)]
-mod tests;
-
-pub mod eh;
-
-use core::mem;
-
-pub struct DwarfReader {
-    pub ptr: *const u8,
-}
-
-#[repr(C, packed)]
-struct Unaligned<T>(T);
-
-impl DwarfReader {
-    pub fn new(ptr: *const u8) -> DwarfReader {
-        DwarfReader { ptr }
-    }
-
-    // DWARF streams are packed, so e.g., a u32 would not necessarily be aligned
-    // on a 4-byte boundary. This may cause problems on platforms with strict
-    // alignment requirements. By wrapping data in a "packed" struct, we are
-    // telling the backend to generate "misalignment-safe" code.
-    pub unsafe fn read<T: Copy>(&mut self) -> T {
-        let Unaligned(result) = *(self.ptr as *const Unaligned<T>);
-        self.ptr = self.ptr.add(mem::size_of::<T>());
-        result
-    }
-
-    // ULEB128 and SLEB128 encodings are defined in Section 7.6 - "Variable
-    // Length Data".
-    pub unsafe fn read_uleb128(&mut self) -> u64 {
-        let mut shift: usize = 0;
-        let mut result: u64 = 0;
-        let mut byte: u8;
-        loop {
-            byte = self.read::<u8>();
-            result |= ((byte & 0x7F) as u64) << shift;
-            shift += 7;
-            if byte & 0x80 == 0 {
-                break;
-            }
-        }
-        result
-    }
-
-    pub unsafe fn read_sleb128(&mut self) -> i64 {
-        let mut shift: u32 = 0;
-        let mut result: u64 = 0;
-        let mut byte: u8;
-        loop {
-            byte = self.read::<u8>();
-            result |= ((byte & 0x7F) as u64) << shift;
-            shift += 7;
-            if byte & 0x80 == 0 {
-                break;
-            }
-        }
-        // sign-extend
-        if shift < u64::BITS && (byte & 0x40) != 0 {
-            result |= (!0 as u64) << shift;
-        }
-        result as i64
-    }
-}
diff --git a/library/panic_unwind/src/dwarf/tests.rs b/library/panic_unwind/src/dwarf/tests.rs
deleted file mode 100644
index 1644f37083a..00000000000
--- a/library/panic_unwind/src/dwarf/tests.rs
+++ /dev/null
@@ -1,19 +0,0 @@
-use super::*;
-
-#[test]
-fn dwarf_reader() {
-    let encoded: &[u8] = &[1, 2, 3, 4, 5, 6, 7, 0xE5, 0x8E, 0x26, 0x9B, 0xF1, 0x59, 0xFF, 0xFF];
-
-    let mut reader = DwarfReader::new(encoded.as_ptr());
-
-    unsafe {
-        assert!(reader.read::<u8>() == u8::to_be(1u8));
-        assert!(reader.read::<u16>() == u16::to_be(0x0203));
-        assert!(reader.read::<u32>() == u32::to_be(0x04050607));
-
-        assert!(reader.read_uleb128() == 624485);
-        assert!(reader.read_sleb128() == -624485);
-
-        assert!(reader.read::<i8>() == i8::to_be(-1));
-    }
-}
diff --git a/library/panic_unwind/src/emcc.rs b/library/panic_unwind/src/emcc.rs
index 1ee69ff9cb2..7c233c7c3a1 100644
--- a/library/panic_unwind/src/emcc.rs
+++ b/library/panic_unwind/src/emcc.rs
@@ -12,7 +12,6 @@ use core::intrinsics;
 use core::mem;
 use core::ptr;
 use core::sync::atomic::{AtomicBool, Ordering};
-use libc::{self, c_int};
 use unwind as uw;
 
 // This matches the layout of std::type_info in C++
@@ -105,21 +104,6 @@ extern "C" fn exception_cleanup(ptr: *mut libc::c_void) -> *mut libc::c_void {
     }
 }
 
-// This is required by the compiler to exist (e.g., it's a lang item), but it's
-// never actually called by the compiler.  Emscripten EH doesn't use a
-// personality function at all, it instead uses __cxa_find_matching_catch.
-// Wasm error handling would use __gxx_personality_wasm0.
-#[lang = "eh_personality"]
-unsafe extern "C" fn rust_eh_personality(
-    _version: c_int,
-    _actions: uw::_Unwind_Action,
-    _exception_class: uw::_Unwind_Exception_Class,
-    _exception_object: *mut uw::_Unwind_Exception,
-    _context: *mut uw::_Unwind_Context,
-) -> uw::_Unwind_Reason_Code {
-    core::intrinsics::abort()
-}
-
 extern "C" {
     fn __cxa_allocate_exception(thrown_size: libc::size_t) -> *mut libc::c_void;
     fn __cxa_begin_catch(thrown_exception: *mut libc::c_void) -> *mut libc::c_void;
diff --git a/library/panic_unwind/src/gcc.rs b/library/panic_unwind/src/gcc.rs
index a596592311a..a5642178c8e 100644
--- a/library/panic_unwind/src/gcc.rs
+++ b/library/panic_unwind/src/gcc.rs
@@ -39,8 +39,6 @@
 use alloc::boxed::Box;
 use core::any::Any;
 
-use crate::dwarf::eh::{self, EHAction, EHContext};
-use libc::{c_int, uintptr_t};
 use unwind as uw;
 
 #[repr(C)]
@@ -90,232 +88,6 @@ fn rust_exception_class() -> uw::_Unwind_Exception_Class {
     0x4d4f5a_00_52555354
 }
 
-// Register ids were lifted from LLVM's TargetLowering::getExceptionPointerRegister()
-// and TargetLowering::getExceptionSelectorRegister() for each architecture,
-// then mapped to DWARF register numbers via register definition tables
-// (typically <arch>RegisterInfo.td, search for "DwarfRegNum").
-// See also https://llvm.org/docs/WritingAnLLVMBackend.html#defining-a-register.
-
-#[cfg(target_arch = "x86")]
-const UNWIND_DATA_REG: (i32, i32) = (0, 2); // EAX, EDX
-
-#[cfg(target_arch = "x86_64")]
-const UNWIND_DATA_REG: (i32, i32) = (0, 1); // RAX, RDX
-
-#[cfg(any(target_arch = "arm", target_arch = "aarch64"))]
-const UNWIND_DATA_REG: (i32, i32) = (0, 1); // R0, R1 / X0, X1
-
-#[cfg(target_arch = "m68k")]
-const UNWIND_DATA_REG: (i32, i32) = (0, 1); // D0, D1
-
-#[cfg(any(target_arch = "mips", target_arch = "mips64"))]
-const UNWIND_DATA_REG: (i32, i32) = (4, 5); // A0, A1
-
-#[cfg(any(target_arch = "powerpc", target_arch = "powerpc64"))]
-const UNWIND_DATA_REG: (i32, i32) = (3, 4); // R3, R4 / X3, X4
-
-#[cfg(target_arch = "s390x")]
-const UNWIND_DATA_REG: (i32, i32) = (6, 7); // R6, R7
-
-#[cfg(any(target_arch = "sparc", target_arch = "sparc64"))]
-const UNWIND_DATA_REG: (i32, i32) = (24, 25); // I0, I1
-
-#[cfg(target_arch = "hexagon")]
-const UNWIND_DATA_REG: (i32, i32) = (0, 1); // R0, R1
-
-#[cfg(any(target_arch = "riscv64", target_arch = "riscv32"))]
-const UNWIND_DATA_REG: (i32, i32) = (10, 11); // x10, x11
-
-// The following code is based on GCC's C and C++ personality routines.  For reference, see:
-// https://github.com/gcc-mirror/gcc/blob/master/libstdc++-v3/libsupc++/eh_personality.cc
-// https://github.com/gcc-mirror/gcc/blob/trunk/libgcc/unwind-c.c
-
-cfg_if::cfg_if! {
-    if #[cfg(all(target_arch = "arm", not(target_os = "ios"), not(target_os = "watchos"), not(target_os = "netbsd")))] {
-        // ARM EHABI personality routine.
-        // https://infocenter.arm.com/help/topic/com.arm.doc.ihi0038b/IHI0038B_ehabi.pdf
-        //
-        // iOS uses the default routine instead since it uses SjLj unwinding.
-        #[lang = "eh_personality"]
-        unsafe extern "C" fn rust_eh_personality(state: uw::_Unwind_State,
-                                                 exception_object: *mut uw::_Unwind_Exception,
-                                                 context: *mut uw::_Unwind_Context)
-                                                 -> uw::_Unwind_Reason_Code {
-            let state = state as c_int;
-            let action = state & uw::_US_ACTION_MASK as c_int;
-            let search_phase = if action == uw::_US_VIRTUAL_UNWIND_FRAME as c_int {
-                // Backtraces on ARM will call the personality routine with
-                // state == _US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND. In those cases
-                // we want to continue unwinding the stack, otherwise all our backtraces
-                // would end at __rust_try
-                if state & uw::_US_FORCE_UNWIND as c_int != 0 {
-                    return continue_unwind(exception_object, context);
-                }
-                true
-            } else if action == uw::_US_UNWIND_FRAME_STARTING as c_int {
-                false
-            } else if action == uw::_US_UNWIND_FRAME_RESUME as c_int {
-                return continue_unwind(exception_object, context);
-            } else {
-                return uw::_URC_FAILURE;
-            };
-
-            // The DWARF unwinder assumes that _Unwind_Context holds things like the function
-            // and LSDA pointers, however ARM EHABI places them into the exception object.
-            // To preserve signatures of functions like _Unwind_GetLanguageSpecificData(), which
-            // take only the context pointer, GCC personality routines stash a pointer to
-            // exception_object in the context, using location reserved for ARM's
-            // "scratch register" (r12).
-            uw::_Unwind_SetGR(context,
-                              uw::UNWIND_POINTER_REG,
-                              exception_object as uw::_Unwind_Ptr);
-            // ...A more principled approach would be to provide the full definition of ARM's
-            // _Unwind_Context in our libunwind bindings and fetch the required data from there
-            // directly, bypassing DWARF compatibility functions.
-
-            let eh_action = match find_eh_action(context) {
-                Ok(action) => action,
-                Err(_) => return uw::_URC_FAILURE,
-            };
-            if search_phase {
-                match eh_action {
-                    EHAction::None |
-                    EHAction::Cleanup(_) => return continue_unwind(exception_object, context),
-                    EHAction::Catch(_) => {
-                        // EHABI requires the personality routine to update the
-                        // SP value in the barrier cache of the exception object.
-                        (*exception_object).private[5] =
-                            uw::_Unwind_GetGR(context, uw::UNWIND_SP_REG);
-                        return uw::_URC_HANDLER_FOUND;
-                    }
-                    EHAction::Terminate => return uw::_URC_FAILURE,
-                }
-            } else {
-                match eh_action {
-                    EHAction::None => return continue_unwind(exception_object, context),
-                    EHAction::Cleanup(lpad) |
-                    EHAction::Catch(lpad) => {
-                        uw::_Unwind_SetGR(context, UNWIND_DATA_REG.0,
-                                          exception_object as uintptr_t);
-                        uw::_Unwind_SetGR(context, UNWIND_DATA_REG.1, 0);
-                        uw::_Unwind_SetIP(context, lpad);
-                        return uw::_URC_INSTALL_CONTEXT;
-                    }
-                    EHAction::Terminate => return uw::_URC_FAILURE,
-                }
-            }
-
-            // On ARM EHABI the personality routine is responsible for actually
-            // unwinding a single stack frame before returning (ARM EHABI Sec. 6.1).
-            unsafe fn continue_unwind(exception_object: *mut uw::_Unwind_Exception,
-                                      context: *mut uw::_Unwind_Context)
-                                      -> uw::_Unwind_Reason_Code {
-                if __gnu_unwind_frame(exception_object, context) == uw::_URC_NO_REASON {
-                    uw::_URC_CONTINUE_UNWIND
-                } else {
-                    uw::_URC_FAILURE
-                }
-            }
-            // defined in libgcc
-            extern "C" {
-                fn __gnu_unwind_frame(exception_object: *mut uw::_Unwind_Exception,
-                                      context: *mut uw::_Unwind_Context)
-                                      -> uw::_Unwind_Reason_Code;
-            }
-        }
-    } else {
-        // Default personality routine, which is used directly on most targets
-        // and indirectly on Windows x86_64 via SEH.
-        unsafe extern "C" fn rust_eh_personality_impl(version: c_int,
-                                                      actions: uw::_Unwind_Action,
-                                                      _exception_class: uw::_Unwind_Exception_Class,
-                                                      exception_object: *mut uw::_Unwind_Exception,
-                                                      context: *mut uw::_Unwind_Context)
-                                                      -> uw::_Unwind_Reason_Code {
-            if version != 1 {
-                return uw::_URC_FATAL_PHASE1_ERROR;
-            }
-            let eh_action = match find_eh_action(context) {
-                Ok(action) => action,
-                Err(_) => return uw::_URC_FATAL_PHASE1_ERROR,
-            };
-            if actions as i32 & uw::_UA_SEARCH_PHASE as i32 != 0 {
-                match eh_action {
-                    EHAction::None |
-                    EHAction::Cleanup(_) => uw::_URC_CONTINUE_UNWIND,
-                    EHAction::Catch(_) => uw::_URC_HANDLER_FOUND,
-                    EHAction::Terminate => uw::_URC_FATAL_PHASE1_ERROR,
-                }
-            } else {
-                match eh_action {
-                    EHAction::None => uw::_URC_CONTINUE_UNWIND,
-                    EHAction::Cleanup(lpad) |
-                    EHAction::Catch(lpad) => {
-                        uw::_Unwind_SetGR(context, UNWIND_DATA_REG.0,
-                            exception_object as uintptr_t);
-                        uw::_Unwind_SetGR(context, UNWIND_DATA_REG.1, 0);
-                        uw::_Unwind_SetIP(context, lpad);
-                        uw::_URC_INSTALL_CONTEXT
-                    }
-                    EHAction::Terminate => uw::_URC_FATAL_PHASE2_ERROR,
-                }
-            }
-        }
-
-        cfg_if::cfg_if! {
-            if #[cfg(all(windows, target_arch = "x86_64", target_env = "gnu"))] {
-                // On x86_64 MinGW targets, the unwinding mechanism is SEH however the unwind
-                // handler data (aka LSDA) uses GCC-compatible encoding.
-                #[lang = "eh_personality"]
-                #[allow(nonstandard_style)]
-                unsafe extern "C" fn rust_eh_personality(exceptionRecord: *mut uw::EXCEPTION_RECORD,
-                        establisherFrame: uw::LPVOID,
-                        contextRecord: *mut uw::CONTEXT,
-                        dispatcherContext: *mut uw::DISPATCHER_CONTEXT)
-                        -> uw::EXCEPTION_DISPOSITION {
-                    uw::_GCC_specific_handler(exceptionRecord,
-                                             establisherFrame,
-                                             contextRecord,
-                                             dispatcherContext,
-                                             rust_eh_personality_impl)
-                }
-            } else {
-                // The personality routine for most of our targets.
-                #[lang = "eh_personality"]
-                unsafe extern "C" fn rust_eh_personality(version: c_int,
-                        actions: uw::_Unwind_Action,
-                        exception_class: uw::_Unwind_Exception_Class,
-                        exception_object: *mut uw::_Unwind_Exception,
-                        context: *mut uw::_Unwind_Context)
-                        -> uw::_Unwind_Reason_Code {
-                    rust_eh_personality_impl(version,
-                                             actions,
-                                             exception_class,
-                                             exception_object,
-                                             context)
-                }
-            }
-        }
-    }
-}
-
-unsafe fn find_eh_action(context: *mut uw::_Unwind_Context) -> Result<EHAction, ()> {
-    let lsda = uw::_Unwind_GetLanguageSpecificData(context) as *const u8;
-    let mut ip_before_instr: c_int = 0;
-    let ip = uw::_Unwind_GetIPInfo(context, &mut ip_before_instr);
-    let eh_context = EHContext {
-        // The return address points 1 byte past the call instruction,
-        // which could be in the next IP range in LSDA range table.
-        //
-        // `ip = -1` has special meaning, so use wrapping sub to allow for that
-        ip: if ip_before_instr != 0 { ip } else { ip.wrapping_sub(1) },
-        func_start: uw::_Unwind_GetRegionStart(context),
-        get_text_start: &|| uw::_Unwind_GetTextRelBase(context),
-        get_data_start: &|| uw::_Unwind_GetDataRelBase(context),
-    };
-    eh::find_eh_action(lsda, &eh_context)
-}
-
 // Frame unwind info registration
 //
 // Each module's image contains a frame unwind info section (usually
diff --git a/library/panic_unwind/src/lib.rs b/library/panic_unwind/src/lib.rs
index f9acb42c46b..55c3c90c428 100644
--- a/library/panic_unwind/src/lib.rs
+++ b/library/panic_unwind/src/lib.rs
@@ -92,8 +92,6 @@ extern "C" {
     fn __rust_foreign_exception() -> !;
 }
 
-mod dwarf;
-
 #[rustc_std_internal_symbol]
 #[allow(improper_ctypes_definitions)]
 pub unsafe extern "C" fn __rust_panic_cleanup(payload: *mut u8) -> *mut (dyn Any + Send + 'static) {
diff --git a/library/panic_unwind/src/seh.rs b/library/panic_unwind/src/seh.rs
index aa7096b1157..f71c47270ee 100644
--- a/library/panic_unwind/src/seh.rs
+++ b/library/panic_unwind/src/seh.rs
@@ -323,13 +323,3 @@ pub unsafe fn cleanup(payload: *mut u8) -> Box<dyn Any + Send> {
         exception.data.take().unwrap()
     }
 }
-
-// This is required by the compiler to exist (e.g., it's a lang item), but
-// it's never actually called by the compiler because _CxxFrameHandler3
-// is the personality function that is always used.
-// Hence this is just an aborting stub.
-#[lang = "eh_personality"]
-#[cfg(not(test))]
-fn rust_eh_personality() {
-    core::intrinsics::abort()
-}