Print thread ID in panic message

library/std/src/panicking.rs

@@ -269,6 +269,7 @@ fn default_hook(info: &PanicHookInfo<'_>) {
 
         thread::with_current_name(|name| {
             let name = name.unwrap_or("<unnamed>");
+            let tid = thread::current_os_id();
 
             // Try to write the panic message to a buffer first to prevent other concurrent outputs
             // interleaving with it.
@@ -277,7 +278,7 @@ fn default_hook(info: &PanicHookInfo<'_>) {
 
             let write_msg = |dst: &mut dyn crate::io::Write| {
                 // We add a newline to ensure the panic message appears at the start of a line.
-                writeln!(dst, "\nthread '{name}' panicked at {location}:\n{msg}")
+                writeln!(dst, "\nthread '{name}' ({tid}) panicked at {location}:\n{msg}")
             };
 
             if write_msg(&mut cursor).is_ok() {

library/std/src/sys/pal/hermit/thread.rs

@@ -103,6 +103,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     unsafe { Ok(NonZero::new_unchecked(hermit_abi::available_parallelism())) }
 }

library/std/src/sys/pal/itron/thread.rs

@@ -349,6 +349,10 @@ unsafe fn terminate_and_delete_current_task() -> ! {
     unsafe { crate::hint::unreachable_unchecked() };
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     super::unsupported()
 }

library/std/src/sys/pal/sgx/thread.rs

@@ -1,6 +1,6 @@
 #![cfg_attr(test, allow(dead_code))] // why is this necessary?
 
-use super::abi::usercalls;
+use super::abi::{thread, usercalls};
 use super::unsupported;
 use crate::ffi::CStr;
 use crate::io;
@@ -137,6 +137,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    Some(thread::current().addr().get() as u64)
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     unsupported()
 }

library/std/src/sys/pal/teeos/thread.rs

@@ -132,6 +132,10 @@ impl Drop for Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 // Note: Both `sched_getaffinity` and `sysconf` are available but not functional on
 // teeos, so this function always returns an Error!
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {

library/std/src/sys/pal/uefi/thread.rs

@@ -44,6 +44,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     // UEFI is single threaded
     Ok(NonZero::new(1).unwrap())

library/std/src/sys/pal/unix/stack_overflow.rs

@@ -120,7 +120,8 @@ mod imp {
                     && thread_info.guard_page_range.contains(&fault_addr)
                 {
                     let name = thread_info.thread_name.as_deref().unwrap_or("<unknown>");
-                    rtprintpanic!("\nthread '{name}' has overflowed its stack\n");
+                    let tid = crate::thread::current_os_id();
+                    rtprintpanic!("\nthread '{name}' ({tid}) has overflowed its stack\n");
                     rtabort!("stack overflow");
                 }
             })
@@ -696,7 +697,8 @@ mod imp {
             if code == c::EXCEPTION_STACK_OVERFLOW {
                 crate::thread::with_current_name(|name| {
                     let name = name.unwrap_or("<unknown>");
-                    rtprintpanic!("\nthread '{name}' has overflowed its stack\n");
+                    let tid = crate::thread::current_os_id();
+                    rtprintpanic!("\nthread '{name}' ({tid}) has overflowed its stack\n");
                 });
             }
             c::EXCEPTION_CONTINUE_SEARCH

library/std/src/sys/pal/unix/thread.rs

@@ -318,6 +318,62 @@ impl Drop for Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    // Most Unix platforms have a way to query an integer ID of the current thread, all with
+    // slightly different spellings.
+    //
+    // The OS thread ID is used rather than `pthread_self` so as to match what will be displayed
+    // for process inspection (debuggers, trace, `top`, etc.).
+    cfg_if::cfg_if! {
+        // Most platforms have a function returning a `pid_t` or int, which is an `i32`.
+        if #[cfg(any(target_os = "android", target_os = "linux"))] {
+            use crate::sys::weak::syscall;
+
+            // `libc::gettid` is only available on glibc 2.30+, but the syscall is available
+            // since Linux 2.4.11.
+            syscall!(fn gettid() -> libc::pid_t;);
+
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::pid_t = unsafe { gettid() };
+            Some(id as u64)
+        } else if #[cfg(target_os = "nto")] {
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::pid_t = unsafe { libc::gettid() };
+            Some(id as u64)
+        } else if #[cfg(target_os = "openbsd")] {
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::pid_t = unsafe { libc::getthrid() };
+            Some(id as u64)
+        } else if #[cfg(target_os = "freebsd")] {
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::c_int = unsafe { libc::pthread_getthreadid_np() };
+            Some(id as u64)
+        } else if #[cfg(target_os = "netbsd")] {
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::lwpid_t = unsafe { libc::_lwp_self() };
+            Some(id as u64)
+        } else if #[cfg(any(target_os = "illumos", target_os = "solaris"))] {
+            // On Illumos and Solaris, the `pthread_t` is the same as the OS thread ID.
+            // SAFETY: FFI call with no preconditions.
+            let id: libc::pthread_t = unsafe { libc::pthread_self() };
+            Some(id as u64)
+        } else if #[cfg(target_vendor = "apple")] {
+            // Apple allows querying arbitrary thread IDs, `thread=NULL` queries the current thread.
+            let mut id = 0u64;
+            // SAFETY: `thread_id` is a valid pointer, no other preconditions.
+            let status: libc::c_int = unsafe { libc::pthread_threadid_np(0, &mut id) };
+            if status == 0 {
+                Some(id)
+            } else {
+                None
+            }
+        } else {
+            // Other platforms don't have an OS thread ID or don't have a way to access it.
+            None
+        }
+    }
+}
+
 #[cfg(any(
     target_os = "linux",
     target_os = "nto",

library/std/src/sys/pal/unsupported/thread.rs

@@ -31,6 +31,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     unsupported()
 }

library/std/src/sys/pal/wasi/thread.rs

@@ -186,6 +186,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     cfg_if::cfg_if! {
         if #[cfg(target_feature = "atomics")] {

library/std/src/sys/pal/windows/c/bindings.txt

@@ -2185,6 +2185,7 @@ GetSystemInfo
 GetSystemTimeAsFileTime
 GetSystemTimePreciseAsFileTime
 GetTempPathW
+GetThreadId
 GetUserProfileDirectoryW
 GetWindowsDirectoryW
 HANDLE

library/std/src/sys/pal/windows/c/windows_sys.rs

@@ -61,6 +61,7 @@ windows_targets::link!("kernel32.dll" "system" fn GetSystemInfo(lpsysteminfo : *
 windows_targets::link!("kernel32.dll" "system" fn GetSystemTimeAsFileTime(lpsystemtimeasfiletime : *mut FILETIME));
 windows_targets::link!("kernel32.dll" "system" fn GetSystemTimePreciseAsFileTime(lpsystemtimeasfiletime : *mut FILETIME));
 windows_targets::link!("kernel32.dll" "system" fn GetTempPathW(nbufferlength : u32, lpbuffer : PWSTR) -> u32);
+windows_targets::link!("kernel32.dll" "system" fn GetThreadId(thread : HANDLE) -> u32);
 windows_targets::link!("userenv.dll" "system" fn GetUserProfileDirectoryW(htoken : HANDLE, lpprofiledir : PWSTR, lpcchsize : *mut u32) -> BOOL);
 windows_targets::link!("kernel32.dll" "system" fn GetWindowsDirectoryW(lpbuffer : PWSTR, usize : u32) -> u32);
 windows_targets::link!("kernel32.dll" "system" fn InitOnceBeginInitialize(lpinitonce : *mut INIT_ONCE, dwflags : u32, fpending : *mut BOOL, lpcontext : *mut *mut core::ffi::c_void) -> BOOL);

library/std/src/sys/pal/windows/stack_overflow.rs

@@ -20,7 +20,8 @@ unsafe extern "system" fn vectored_handler(ExceptionInfo: *mut c::EXCEPTION_POIN
         if code == c::EXCEPTION_STACK_OVERFLOW {
             thread::with_current_name(|name| {
                 let name = name.unwrap_or("<unknown>");
-                rtprintpanic!("\nthread '{name}' has overflowed its stack\n");
+                let tid = thread::current_os_id();
+                rtprintpanic!("\nthread '{name}' ({tid}) has overflowed its stack\n");
             });
         }
         c::EXCEPTION_CONTINUE_SEARCH

library/std/src/sys/pal/windows/thread.rs

@@ -115,6 +115,14 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    // SAFETY: FFI call with no preconditions.
+    let id: u32 = unsafe { c::GetThreadId(c::GetCurrentThread()) };
+
+    // A return value of 0 indicates failed lookup.
+    if id == 0 { None } else { Some(id.into()) }
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     let res = unsafe {
         let mut sysinfo: c::SYSTEM_INFO = crate::mem::zeroed();

library/std/src/sys/pal/xous/thread.rs

@@ -133,6 +133,10 @@ impl Thread {
     }
 }
 
+pub(crate) fn current_os_id() -> Option<u64> {
+    None
+}
+
 pub fn available_parallelism() -> io::Result<NonZero<usize>> {
     // We're unicore right now.
     Ok(unsafe { NonZero::new_unchecked(1) })

library/std/src/thread/current.rs

@@ -1,4 +1,4 @@
-use super::{Thread, ThreadId};
+use super::{Thread, ThreadId, imp};
 use crate::mem::ManuallyDrop;
 use crate::ptr;
 use crate::sys::thread_local::local_pointer;
@@ -148,6 +148,17 @@ pub(crate) fn current_id() -> ThreadId {
     id::get_or_init()
 }
 
+/// Gets the OS thread ID of the thread that invokes it, if available. If not, return the Rust
+/// thread ID.
+///
+/// We use a `u64` to all possible platform IDs without excess `cfg`; most use `int`, some use a
+/// pointer, and Apple uses `uint64_t`. This is a "best effort" approach for diagnostics and is
+/// allowed to fall back to a non-OS ID (such as the Rust thread ID) or a non-unique ID (such as a
+/// PID) if the thread ID cannot be retrieved.
+pub(crate) fn current_os_id() -> u64 {
+    imp::current_os_id().unwrap_or_else(|| current_id().as_u64().get())
+}
+
 /// Gets a reference to the handle of the thread that invokes it, if the handle
 /// has been initialized.
 pub(super) fn try_with_current<F, R>(f: F) -> R

library/std/src/thread/mod.rs

@@ -183,7 +183,7 @@ mod current;
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use current::current;
-pub(crate) use current::{current_id, current_or_unnamed, drop_current};
+pub(crate) use current::{current_id, current_or_unnamed, current_os_id, drop_current};
 use current::{set_current, try_with_current};
 
 mod spawnhook;

library/std/src/thread/tests.rs

@@ -346,6 +346,13 @@ fn test_thread_id_not_equal() {
     assert!(thread::current().id() != spawned_id);
 }
 
+#[test]
+fn test_thread_os_id_not_equal() {
+    let spawned_id = thread::spawn(|| thread::current_os_id()).join().unwrap();
+    let current_id = thread::current_os_id();
+    assert!(current_id != spawned_id);
+}
+
 #[test]
 fn test_scoped_threads_drop_result_before_join() {
     let actually_finished = &AtomicBool::new(false);

src/tools/compiletest/src/runtest.rs

@@ -2524,6 +2524,11 @@ impl<'test> TestCx<'test> {
                 })
                 .into_owned();
 
+        // Normalize thread IDs in panic messages
+        normalized = static_regex!(r"thread '(?P<name>.*?)' \((rtid )?\d+\) panicked")
+            .replace_all(&normalized, "thread '$name' ($$TID) panicked")
+            .into_owned();
+
         normalized = normalized.replace("\t", "\\t"); // makes tabs visible
 
         // Remove test annotations like `//~ ERROR text` from the output,

src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind1.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/function_calls/exported_symbol_bad_unwind1.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/function_calls/exported_symbol_bad_unwind1.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect

src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr

@@ -1,10 +1,10 @@
 
-thread 'main' panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect
 
-thread 'main' panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
 panic in a function that cannot unwind
 stack backtrace:
 thread caused non-unwinding panic. aborting.

src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr

@@ -1,10 +1,10 @@
 
-thread 'main' panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect
 
-thread 'main' panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
 panic in a function that cannot unwind
 stack backtrace:
 thread caused non-unwinding panic. aborting.

src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.extern_block.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/function_calls/exported_symbol_bad_unwind2.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect

src/tools/miri/tests/fail/function_calls/return_pointer_on_unwind.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/function_calls/return_pointer_on_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/function_calls/return_pointer_on_unwind.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect

src/tools/miri/tests/fail/panic/abort_unwind.stderr

@@ -1,10 +1,10 @@
 
-thread 'main' panicked at tests/fail/panic/abort_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/abort_unwind.rs:LL:CC:
 PANIC!!!
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect
 
-thread 'main' panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
 panic in a function that cannot unwind
 stack backtrace:
 thread caused non-unwinding panic. aborting.

src/tools/miri/tests/fail/panic/bad_unwind.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/panic/bad_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/bad_unwind.rs:LL:CC:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect

src/tools/miri/tests/fail/panic/double_panic.stderr

@@ -1,14 +1,14 @@
 
-thread 'main' panicked at tests/fail/panic/double_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/double_panic.rs:LL:CC:
 first
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect
 
-thread 'main' panicked at tests/fail/panic/double_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/double_panic.rs:LL:CC:
 second
 stack backtrace:
 
-thread 'main' panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/core/src/panicking.rs:LL:CC:
 panic in a destructor during cleanup
 thread caused non-unwinding panic. aborting.
 error: abnormal termination: the program aborted execution

src/tools/miri/tests/fail/panic/panic_abort1.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/panic/panic_abort1.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/panic_abort1.rs:LL:CC:
 panicking from libstd
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect

src/tools/miri/tests/fail/panic/panic_abort2.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/panic/panic_abort2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/panic_abort2.rs:LL:CC:
 42-panicking from libstd
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 note: in Miri, you may have to set `MIRIFLAGS=-Zmiri-env-forward=RUST_BACKTRACE` for the environment variable to have an effect