Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 155 insertions, 0 deletions

diff --git a/library/panic_abort/src/lib.rs b/library/panic_abort/src/lib.rs
new file mode 100644
index 000000000..8801c670b
--- /dev/null
+++ b/library/panic_abort/src/lib.rs
@@ -0,0 +1,155 @@
+//! Implementation of Rust panics via process aborts
+//!
+//! When compared to the implementation via unwinding, this crate is *much*
+//! simpler! That being said, it's not quite as versatile, but here goes!
+
+#![no_std]
+#![unstable(feature = "panic_abort", issue = "32837")]
+#![doc(issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/")]
+#![panic_runtime]
+#![allow(unused_features)]
+#![feature(core_intrinsics)]
+#![feature(panic_runtime)]
+#![feature(std_internals)]
+#![feature(staged_api)]
+#![feature(rustc_attrs)]
+#![feature(c_unwind)]
+
+#[cfg(target_os = "android")]
+mod android;
+
+use core::any::Any;
+use core::panic::BoxMeUp;
+
+#[rustc_std_internal_symbol]
+#[allow(improper_ctypes_definitions)]
+pub unsafe extern "C" fn __rust_panic_cleanup(_: *mut u8) -> *mut (dyn Any + Send + 'static) {
+    unreachable!()
+}
+
+// "Leak" the payload and shim to the relevant abort on the platform in question.
+#[rustc_std_internal_symbol]
+pub unsafe fn __rust_start_panic(_payload: *mut &mut dyn BoxMeUp) -> u32 {
+    // Android has the ability to attach a message as part of the abort.
+    #[cfg(target_os = "android")]
+    android::android_set_abort_message(_payload);
+
+    abort();
+
+    cfg_if::cfg_if! {
+        if #[cfg(any(unix, target_os = "solid_asp3"))] {
+            unsafe fn abort() -> ! {
+                libc::abort();
+            }
+        } else if #[cfg(any(target_os = "hermit",
+                            all(target_vendor = "fortanix", target_env = "sgx")
+        ))] {
+            unsafe fn abort() -> ! {
+                // call std::sys::abort_internal
+                extern "C" {
+                    pub fn __rust_abort() -> !;
+                }
+                __rust_abort();
+            }
+        } else if #[cfg(all(windows, not(miri)))] {
+            // On Windows, use the processor-specific __fastfail mechanism. In Windows 8
+            // and later, this will terminate the process immediately without running any
+            // in-process exception handlers. In earlier versions of Windows, this
+            // sequence of instructions will be treated as an access violation,
+            // terminating the process but without necessarily bypassing all exception
+            // handlers.
+            //
+            // https://docs.microsoft.com/en-us/cpp/intrinsics/fastfail
+            //
+            // Note: this is the same implementation as in libstd's `abort_internal`
+            unsafe fn abort() -> ! {
+                #[allow(unused)]
+                const FAST_FAIL_FATAL_APP_EXIT: usize = 7;
+                cfg_if::cfg_if! {
+                    if #[cfg(any(target_arch = "x86", target_arch = "x86_64"))] {
+                        core::arch::asm!("int $$0x29", in("ecx") FAST_FAIL_FATAL_APP_EXIT);
+                    } else if #[cfg(all(target_arch = "arm", target_feature = "thumb-mode"))] {
+                        core::arch::asm!(".inst 0xDEFB", in("r0") FAST_FAIL_FATAL_APP_EXIT);
+                    } else if #[cfg(target_arch = "aarch64")] {
+                        core::arch::asm!("brk 0xF003", in("x0") FAST_FAIL_FATAL_APP_EXIT);
+                    } else {
+                        core::intrinsics::abort();
+                    }
+                }
+                core::intrinsics::unreachable();
+            }
+        } else {
+            unsafe fn abort() -> ! {
+                core::intrinsics::abort();
+            }
+        }
+    }
+}
+
+// This... is a bit of an oddity. The tl;dr; is that this is required to link
+// correctly, the longer explanation is below.
+//
+// Right now the binaries of libcore/libstd that we ship are all compiled with
+// `-C panic=unwind`. This is done to ensure that the binaries are maximally
+// compatible with as many situations as possible. The compiler, however,
+// requires a "personality function" for all functions compiled with `-C
+// panic=unwind`. This personality function is hardcoded to the symbol
+// `rust_eh_personality` and is defined by the `eh_personality` lang item.
+//
+// So... why not just define that lang item here? Good question! The way that
+// panic runtimes are linked in is actually a little subtle in that they're
+// "sort of" in the compiler's crate store, but only actually linked if another
+// isn't actually linked. This ends up meaning that both this crate and the
+// panic_unwind crate can appear in the compiler's crate store, and if both
+// define the `eh_personality` lang item then that'll hit an error.
+//
+// To handle this the compiler only requires the `eh_personality` is defined if
+// the panic runtime being linked in is the unwinding runtime, and otherwise
+// it's not required to be defined (rightfully so). In this case, however, this
+// library just defines this symbol so there's at least some personality
+// somewhere.
+//
+// Essentially this symbol is just defined to get wired up to libcore/libstd
+// binaries, but it should never be called as we don't link in an unwinding
+// runtime at all.
+pub mod personalities {
+    #[rustc_std_internal_symbol]
+    #[cfg(not(any(
+        all(target_family = "wasm", not(target_os = "emscripten")),
+        all(target_os = "windows", target_env = "gnu", target_arch = "x86_64",),
+    )))]
+    pub extern "C" fn rust_eh_personality() {}
+
+    // On x86_64-pc-windows-gnu we use our own personality function that needs
+    // to return `ExceptionContinueSearch` as we're passing on all our frames.
+    #[rustc_std_internal_symbol]
+    #[cfg(all(target_os = "windows", target_env = "gnu", target_arch = "x86_64"))]
+    pub extern "C" fn rust_eh_personality(
+        _record: usize,
+        _frame: usize,
+        _context: usize,
+        _dispatcher: usize,
+    ) -> u32 {
+        1 // `ExceptionContinueSearch`
+    }
+
+    // Similar to above, this corresponds to the `eh_catch_typeinfo` lang item
+    // that's only used on Emscripten currently.
+    //
+    // Since panics don't generate exceptions and foreign exceptions are
+    // currently UB with -C panic=abort (although this may be subject to
+    // change), any catch_unwind calls will never use this typeinfo.
+    #[rustc_std_internal_symbol]
+    #[allow(non_upper_case_globals)]
+    #[cfg(target_os = "emscripten")]
+    static rust_eh_catch_typeinfo: [usize; 2] = [0; 2];
+
+    // These two are called by our startup objects on i686-pc-windows-gnu, but
+    // they don't need to do anything so the bodies are nops.
+    #[rustc_std_internal_symbol]
+    #[cfg(all(target_os = "windows", target_env = "gnu", target_arch = "x86"))]
+    pub extern "C" fn rust_eh_register_frames() {}
+    #[rustc_std_internal_symbol]
+    #[cfg(all(target_os = "windows", target_env = "gnu", target_arch = "x86"))]
+    pub extern "C" fn rust_eh_unregister_frames() {}
+}