Install more signal stack trace handlers

Author: Urgau

compiler/rustc_driver_impl/src/signal_handler.rs

@@ -6,6 +6,15 @@ use std::{fmt, mem, ptr, slice};
 
 use rustc_interface::util::{DEFAULT_STACK_SIZE, STACK_SIZE};
 
+/// Signals that represent that we have a bug, and our prompt termination has
+/// been ordered.
+#[rustfmt::skip]
+const KILL_SIGNALS: [(libc::c_int, &str); 3] = [
+    (libc::SIGILL, "SIGILL"),
+    (libc::SIGBUS, "SIGBUS"),
+    (libc::SIGSEGV, "SIGSEGV")
+];
+
 unsafe extern "C" {
     fn backtrace_symbols_fd(buffer: *const *mut libc::c_void, size: libc::c_int, fd: libc::c_int);
 }
@@ -39,8 +48,19 @@ macro raw_errln($tokens:tt) {
 /// # Safety
 ///
 /// Caller must ensure that this function is not re-entered.
-unsafe extern "C" fn print_stack_trace(_: libc::c_int) {
+unsafe extern "C" fn print_stack_trace(signum: libc::c_int) {
     const MAX_FRAMES: usize = 256;
+
+    let signame = {
+        let mut signame = "<unknown>";
+        for sig in KILL_SIGNALS {
+            if sig.0 == signum {
+                signame = sig.1;
+            }
+        }
+        signame
+    };
+
     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
@@ -54,7 +74,8 @@ unsafe extern "C" fn print_stack_trace(_: libc::c_int) {
     };
 
     // Just a stack trace is cryptic. Explain what we're doing.
-    raw_errln!("error: rustc interrupted by SIGSEGV, printing backtrace\n");
+    raw_errln!("error: rustc interrupted by {signame}, printing backtrace\n");
+
     let mut written = 1;
     let mut consumed = 0;
     // Begin elaborating return addrs into symbols and writing them directly to stderr
@@ -106,13 +127,18 @@ unsafe extern "C" fn print_stack_trace(_: libc::c_int) {
         written += 1;
     }
     raw_errln!("note: we would appreciate a report at https://github.com/rust-lang/rust");
-    // get the current stack size WITHOUT blocking and double it
-    let new_size = STACK_SIZE.get().copied().unwrap_or(DEFAULT_STACK_SIZE) * 2;
-    raw_errln!("help: you can increase rustc's stack size by setting RUST_MIN_STACK={new_size}");
-    written += 2;
+    written += 1;
+    if signum == libc::SIGSEGV {
+        // get the current stack size WITHOUT blocking and double it
+        let new_size = STACK_SIZE.get().copied().unwrap_or(DEFAULT_STACK_SIZE) * 2;
+        raw_errln!(
+            "help: you can increase rustc's stack size by setting RUST_MIN_STACK={new_size}"
+        );
+        written += 1;
+    }
     if written > 24 {
         // We probably just scrolled the earlier "we got SIGSEGV" message off the terminal
-        raw_errln!("note: backtrace dumped due to SIGSEGV! resuming signal");
+        raw_errln!("note: backtrace dumped due to {signame}! resuming signal");
     };
 }
 
@@ -129,7 +155,9 @@ pub(super) fn install() {
         sa.sa_sigaction = print_stack_trace as libc::sighandler_t;
         sa.sa_flags = libc::SA_NODEFER | libc::SA_RESETHAND | libc::SA_ONSTACK;
         libc::sigemptyset(&mut sa.sa_mask);
-        libc::sigaction(libc::SIGSEGV, &sa, ptr::null_mut());
+        for (signum, _signame) in KILL_SIGNALS {
+            libc::sigaction(signum, &sa, ptr::null_mut());
+        }
     }
 }