Remove allowing static_mut_refs lint

Author: mu001999

compiler/rustc_driver_impl/src/signal_handler.rs

@@ -2,7 +2,7 @@
 //! Primarily used to extract a backtrace from stack overflow
 
 use std::alloc::{Layout, alloc};
-use std::{fmt, mem, ptr};
+use std::{fmt, mem, ptr, slice};
 
 use rustc_interface::util::{DEFAULT_STACK_SIZE, STACK_SIZE};
 
@@ -35,20 +35,22 @@ macro raw_errln($tokens:tt) {
 }
 
 /// Signal handler installed for SIGSEGV
-// FIXME(static_mut_refs): Do not allow `static_mut_refs` lint
-#[allow(static_mut_refs)]
-extern "C" fn print_stack_trace(_: libc::c_int) {
+///
+/// # Safety
+///
+/// Caller must ensure that this function is not re-entered.
+unsafe extern "C" fn print_stack_trace(_: libc::c_int) {
  const MAX_FRAMES: usize = 256;
- // Reserve data segment so we don't have to malloc in a signal handler, which might fail
- // in incredibly undesirable and unexpected ways due to e.g. the allocator deadlocking
- static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] = [ptr::null_mut(); MAX_FRAMES];
  let stack = unsafe {
+ // Reserve data segment so we don't have to malloc in a signal handler, which might fail
+ // in incredibly undesirable and unexpected ways due to e.g. the allocator deadlocking
+ static mut STACK_TRACE: [*mut libc::c_void; MAX_FRAMES] = [ptr::null_mut(); MAX_FRAMES];
  // Collect return addresses
- let depth = libc::backtrace(STACK_TRACE.as_mut_ptr(), MAX_FRAMES as i32);
+ let depth = libc::backtrace(&raw mut STACK_TRACE as _, MAX_FRAMES as i32);
  if depth == 0 {
  return;
  }
- &STACK_TRACE.as_slice()[0..(depth as _)]
+ slice::from_raw_parts(&raw const STACK_TRACE as _, depth as _)
  };
 
  // Just a stack trace is cryptic. Explain what we're doing.

library/panic_unwind/src/seh.rs

@@ -288,8 +288,6 @@ cfg_if::cfg_if! {
  }
 }
 
-// FIXME(static_mut_refs): Do not allow `static_mut_refs` lint
-#[allow(static_mut_refs)]
 pub unsafe fn panic(data: Box<dyn Any + Send>) -> u32 {
  use core::intrinsics::atomic_store_seqcst;