Print thread ID in panic message if thread name is unknown

`panic!` does not print any identifying information for threads that are
unnamed. However, in many cases, the thread ID can be determined.

This changes the panic message from something like this:

    thread '<unnamed>' panicked at src/main.rs:3:5:
    explicit panic

To something like this:

    thread '<unnamed>' (0xff9bf) panicked at src/main.rs:3:5:
    explicit panic

Stack overflow messages are updated as well.

This change applies to both named and unnamed threads. The ID printed is
the OS integer thread ID rather than the Rust thread ID, which should
also be what debuggers print.

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

@@ -115,6 +115,10 @@ 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

@@ -361,6 +361,10 @@ 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;
@@ -149,6 +149,10 @@ 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

@@ -144,6 +144,10 @@ 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

@@ -56,6 +56,10 @@ 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

@@ -119,7 +119,8 @@ 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

@@ -398,6 +398,62 @@ 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

@@ -39,6 +39,10 @@ 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

@@ -194,6 +194,10 @@ 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

@@ -127,6 +127,14 @@ 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

@@ -145,6 +145,10 @@ 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/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

src/tools/miri/tests/fail/panic/panic_abort3.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/panic/panic_abort3.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/panic_abort3.rs:LL:CC:
 panicking from libcore
 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_abort4.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/panic/panic_abort4.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/panic/panic_abort4.rs:LL:CC:
 42-panicking from libcore
 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/tls_macro_const_drop_panic.stderr

@@ -1,5 +1,5 @@
 
-thread $NAME panicked at tests/fail/panic/tls_macro_const_drop_panic.rs:LL:CC:
+thread $NAME ($TID) panicked at tests/fail/panic/tls_macro_const_drop_panic.rs:LL:CC:
 ow
 fatal runtime error: thread local panicked on drop, aborting
 error: abnormal termination: the program aborted execution

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

@@ -1,5 +1,5 @@
 
-thread $NAME panicked at tests/fail/panic/tls_macro_drop_panic.rs:LL:CC:
+thread $NAME ($TID) panicked at tests/fail/panic/tls_macro_drop_panic.rs:LL:CC:
 ow
 fatal runtime error: thread local panicked on drop, aborting
 error: abnormal termination: the program aborted execution

src/tools/miri/tests/fail/ptr_swap_nonoverlapping.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/fail/ptr_swap_nonoverlapping.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/ptr_swap_nonoverlapping.rs:LL:CC:
 unsafe precondition(s) violated: ptr::swap_nonoverlapping requires that both pointer arguments are aligned and non-null and the specified memory ranges do not overlap
 
 This indicates a bug in the program. This Undefined Behavior check is optional, and cannot be relied on for safety.

src/tools/miri/tests/fail/terminate-terminator.stderr

@@ -1,12 +1,12 @@
 warning: You have explicitly enabled MIR optimizations, overriding Miri's default which is to completely disable them. Any optimizations may hide UB that Miri would otherwise detect, and it is not necessarily possible to predict what kind of UB will be missed. If you are enabling optimizations to make Miri run faster, we advise using cfg(miri) to shrink your workload instead. The performance benefit of enabling MIR optimizations is usually marginal at best.
 
 
-thread 'main' panicked at tests/fail/terminate-terminator.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/terminate-terminator.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/unwind-action-terminate.stderr

@@ -1,10 +1,10 @@
 
-thread 'main' panicked at tests/fail/unwind-action-terminate.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/fail/unwind-action-terminate.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/panic/alloc_error_handler_hook.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/alloc_error_handler_hook.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/alloc_error_handler_hook.rs:LL:CC:
 alloc error hook called
 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/panic/alloc_error_handler_panic.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at RUSTLIB/std/src/alloc.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/std/src/alloc.rs:LL:CC:
 memory allocation of 4 bytes failed
 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/panic/div-by-zero-2.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/div-by-zero-2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/div-by-zero-2.rs:LL:CC:
 attempt to divide by zero
 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/panic/function_calls/exported_symbol_good_unwind.stderr

@@ -1,11 +1,11 @@
 
-thread 'main' panicked at tests/panic/function_calls/exported_symbol_good_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/function_calls/exported_symbol_good_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
 
-thread 'main' panicked at tests/panic/function_calls/exported_symbol_good_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/function_calls/exported_symbol_good_unwind.rs:LL:CC:
 explicit panic
 
-thread 'main' panicked at tests/panic/function_calls/exported_symbol_good_unwind.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/function_calls/exported_symbol_good_unwind.rs:LL:CC:
 explicit panic

src/tools/miri/tests/panic/mir-validation.rs

@@ -8,6 +8,12 @@
 // Somehow on rustc Windows CI, the "Miri caused an ICE" message is not shown
 // and we don't even get a regular panic; rustc aborts with a different exit code instead.
 //@ignore-host: windows
+
+// FIXME: this tests a crash in rustc. For stage1, rustc is built with the downloaded standard
+// library which doesn't yet print the thread ID. Normalization can be removed at the stage bump.
+// For the grep: cfg(bootstrap)
+//@normalize-stderr-test: "thread 'rustc' panicked" -> "thread 'rustc' ($$TID) panicked"
+
 #![feature(custom_mir, core_intrinsics)]
 use core::intrinsics::mir::*;
 

src/tools/miri/tests/panic/mir-validation.stderr

@@ -6,7 +6,7 @@ LL |             *(tuple.0) = 1;
    |             ^^^^^^^^^^^^^^
 
 
-thread 'rustc' panicked at compiler/rustc_mir_transform/src/validate.rs:LL:CC:
+thread 'rustc' ($TID) panicked at compiler/rustc_mir_transform/src/validate.rs:LL:CC:
 Box<dyn Any>
 stack backtrace:
 

src/tools/miri/tests/panic/oob_subslice.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/oob_subslice.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/oob_subslice.rs:LL:CC:
 range end index 5 out of range for slice of length 4
 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/panic/overflowing-lsh-neg.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/overflowing-lsh-neg.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/overflowing-lsh-neg.rs:LL:CC:
 attempt to shift left with overflow
 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/panic/overflowing-rsh-1.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/overflowing-rsh-1.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/overflowing-rsh-1.rs:LL:CC:
 attempt to shift right with overflow
 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/panic/overflowing-rsh-2.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/overflowing-rsh-2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/overflowing-rsh-2.rs:LL:CC:
 attempt to shift right with overflow
 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/panic/panic1.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/panic1.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/panic1.rs:LL:CC:
 panicking from libstd
 stack backtrace:
    0: std::panicking::begin_panic_handler

src/tools/miri/tests/panic/panic2.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/panic2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/panic2.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

src/tools/miri/tests/panic/panic3.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/panic3.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/panic3.rs:LL:CC:
 panicking from libcore
 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/panic/panic4.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/panic4.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/panic4.rs:LL:CC:
 42-panicking from libcore
 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/panic/transmute_fat2.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at tests/panic/transmute_fat2.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/panic/transmute_fat2.rs:LL:CC:
 index out of bounds: the len is 0 but the index is 0
 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/pass/panic/catch_panic.stderr

@@ -1,47 +1,47 @@
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Hello from std::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
 Caught panic message (&str): Hello from std::panic
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Hello from std::panic: 1
 Caught panic message (String): Hello from std::panic: 1
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Hello from std::panic_any: 2
 Caught panic message (String): Hello from std::panic_any: 2
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Box<dyn Any>
 Failed to get caught panic message.
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Hello from core::panic
 Caught panic message (&str): Hello from core::panic
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 Hello from core::panic: 5
 Caught panic message (String): Hello from core::panic: 5
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 index out of bounds: the len is 3 but the index is 4
 Caught panic message (String): index out of bounds: the len is 3 but the index is 4
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 attempt to divide by zero
 Caught panic message (&str): attempt to divide by zero
 
-thread 'main' panicked at RUSTLIB/core/src/ptr/const_ptr.rs:LL:CC:
+thread 'main' ($TID) panicked at RUSTLIB/core/src/ptr/const_ptr.rs:LL:CC:
 align_offset: align is not a power-of-two
 Caught panic message (&str): align_offset: align is not a power-of-two
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 assertion failed: false
 Caught panic message (&str): assertion failed: false
 
-thread 'main' panicked at tests/pass/panic/catch_panic.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/catch_panic.rs:LL:CC:
 assertion failed: false
 Caught panic message (&str): assertion failed: false
 Success!

src/tools/miri/tests/pass/panic/concurrent-panic.stderr

@@ -1,7 +1,7 @@
 Thread 1 starting, will block on mutex
 Thread 1 reported it has started
 
-thread '<unnamed>' panicked at tests/pass/panic/concurrent-panic.rs:LL:CC:
+thread '<unnamed>' ($TID) panicked at tests/pass/panic/concurrent-panic.rs:LL:CC:
 panic in thread 2
 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
@@ -9,7 +9,7 @@ Thread 2 blocking on thread 1
 Thread 2 reported it has started
 Unlocking mutex
 
-thread '<unnamed>' panicked at tests/pass/panic/concurrent-panic.rs:LL:CC:
+thread '<unnamed>' ($TID) panicked at tests/pass/panic/concurrent-panic.rs:LL:CC:
 panic in thread 1
 Thread 1 has exited
 Thread 2 has exited

src/tools/miri/tests/pass/panic/nested_panic_caught.stderr

@@ -1,9 +1,9 @@
 
-thread 'main' panicked at tests/pass/panic/nested_panic_caught.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/nested_panic_caught.rs:LL:CC:
 once
 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/pass/panic/nested_panic_caught.rs:LL:CC:
+thread 'main' ($TID) panicked at tests/pass/panic/nested_panic_caught.rs:LL:CC:
 twice
 stack backtrace:

src/tools/miri/tests/pass/panic/thread_panic.stderr

@@ -1,8 +1,8 @@
 
-thread '<unnamed>' panicked at tests/pass/panic/thread_panic.rs:LL:CC:
+thread '<unnamed>' ($TID) panicked at tests/pass/panic/thread_panic.rs:LL:CC:
 Hello!
 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 'childthread' panicked at tests/pass/panic/thread_panic.rs:LL:CC:
+thread 'childthread' ($TID) panicked at tests/pass/panic/thread_panic.rs:LL:CC:
 Hello, world!

src/tools/rustfmt/tests/rustfmt/main.rs

@@ -185,10 +185,11 @@ fn dont_emit_ICE() {
         "tests/target/issue-6105.rs",
     ];
 
+    let panic_re = regex::Regex::new("thread.*panicked").unwrap();
     for file in files {
         let args = [file];
         let (_stdout, stderr) = rustfmt(&args);
-        assert!(!stderr.contains("thread 'main' panicked"));
+        assert!(!panic_re.is_match(&stderr));
     }
 }
 

tests/run-make/libtest-json/output-default.json

@@ -2,7 +2,7 @@
 { "type": "test", "event": "started", "name": "a" }
 { "type": "test", "name": "a", "event": "ok" }
 { "type": "test", "event": "started", "name": "b" }
-{ "type": "test", "name": "b", "event": "failed", "stdout": "\nthread 'b' panicked at f.rs:9:5:\nassertion failed: false\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
+{ "type": "test", "name": "b", "event": "failed", "stdout": "\nthread 'b' ($TID) panicked at f.rs:9:5:\nassertion failed: false\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
 { "type": "test", "event": "started", "name": "c" }
 { "type": "test", "name": "c", "event": "ok" }
 { "type": "test", "event": "started", "name": "d" }

tests/run-make/libtest-json/output-stdout-success.json

@@ -2,9 +2,9 @@
 { "type": "test", "event": "started", "name": "a" }
 { "type": "test", "name": "a", "event": "ok", "stdout": "print from successful test\n" }
 { "type": "test", "event": "started", "name": "b" }
-{ "type": "test", "name": "b", "event": "failed", "stdout": "\nthread 'b' panicked at f.rs:9:5:\nassertion failed: false\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
+{ "type": "test", "name": "b", "event": "failed", "stdout": "\nthread 'b' ($TID) panicked at f.rs:9:5:\nassertion failed: false\nnote: run with `RUST_BACKTRACE=1` environment variable to display a backtrace\n" }
 { "type": "test", "event": "started", "name": "c" }
-{ "type": "test", "name": "c", "event": "ok", "stdout": "\nthread 'c' panicked at f.rs:15:5:\nassertion failed: false\n" }
+{ "type": "test", "name": "c", "event": "ok", "stdout": "\nthread 'c' ($TID) panicked at f.rs:15:5:\nassertion failed: false\n" }
 { "type": "test", "event": "started", "name": "d" }
 { "type": "test", "name": "d", "event": "ignored", "message": "msg" }
 { "type": "suite", "event": "failed", "passed": 2, "failed": 1, "ignored": 1, "measured": 0, "filtered_out": 0, "exec_time": "$EXEC_TIME" }

tests/run-make/libtest-json/rmake.rs

@@ -38,5 +38,6 @@ fn run_tests(extra_args: &[&str], expected_file: &str) {
         .expected_file(expected_file)
         .actual_text("stdout", test_stdout)
         .normalize(r#"(?<prefix>"exec_time": )[0-9.]+"#, r#"${prefix}"$$EXEC_TIME""#)
+        .normalize(r"thread '(?P<name>.*?)' \(\d+\) panicked", "thread '$name' ($$TID) panicked")
         .run();
 }

tests/run-make/libtest-junit/output-default.xml

@@ -1 +1 @@
-<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="1" tests="4" skipped="1" ><testcase classname="unknown" name="a" time="$TIME"/><testcase classname="unknown" name="b" time="$TIME"><failure type="assert"/><system-out><![CDATA[print from failing test]]>&#xA;&#xA;<![CDATA[thread 'b' panicked at f.rs:10:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="c" time="$TIME"/><system-out/><system-err/></testsuite></testsuites>
+<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="1" tests="4" skipped="1" ><testcase classname="unknown" name="a" time="$TIME"/><testcase classname="unknown" name="b" time="$TIME"><failure type="assert"/><system-out><![CDATA[print from failing test]]>&#xA;&#xA;<![CDATA[thread 'b' ($TID) panicked at f.rs:10:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="c" time="$TIME"/><system-out/><system-err/></testsuite></testsuites>

tests/run-make/libtest-junit/output-stdout-success.xml

@@ -1 +1 @@
-<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="1" tests="4" skipped="1" ><testcase classname="unknown" name="a" time="$TIME"><system-out><![CDATA[print from successful test]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="b" time="$TIME"><failure type="assert"/><system-out><![CDATA[print from failing test]]>&#xA;&#xA;<![CDATA[thread 'b' panicked at f.rs:10:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="c" time="$TIME"><system-out><![CDATA[]]>&#xA;<![CDATA[thread 'c' panicked at f.rs:16:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[]]></system-out></testcase><system-out/><system-err/></testsuite></testsuites>
+<?xml version="1.0" encoding="UTF-8"?><testsuites><testsuite name="test" package="test" id="0" errors="0" failures="1" tests="4" skipped="1" ><testcase classname="unknown" name="a" time="$TIME"><system-out><![CDATA[print from successful test]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="b" time="$TIME"><failure type="assert"/><system-out><![CDATA[print from failing test]]>&#xA;&#xA;<![CDATA[thread 'b' ($TID) panicked at f.rs:10:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace]]>&#xA;<![CDATA[]]></system-out></testcase><testcase classname="unknown" name="c" time="$TIME"><system-out><![CDATA[]]>&#xA;<![CDATA[thread 'c' ($TID) panicked at f.rs:16:5:]]>&#xA;<![CDATA[assertion failed: false]]>&#xA;<![CDATA[]]></system-out></testcase><system-out/><system-err/></testsuite></testsuites>

tests/run-make/libtest-junit/rmake.rs

@@ -27,5 +27,6 @@ fn run_tests(extra_args: &[&str], expected_file: &str) {
         .expected_file(expected_file)
         .actual_text("stdout", test_stdout)
         .normalize(r#"\btime="[0-9.]+""#, r#"time="$$TIME""#)
+        .normalize(r"thread '(?P<name>.*?)' \(\d+\) panicked", "thread '$name' ($$TID) panicked")
         .run();
 }

tests/rustdoc-ui/doctest/edition-2024-error-output.stdout

@@ -9,7 +9,7 @@ Test executable failed (exit status: 101).
 
 stderr:
 
-thread 'main' panicked at $TMP:6:1:
+thread 'main' ($TID) panicked at $TMP:6:1:
 assertion `left == right` failed
   left: 4
  right: 5

tests/rustdoc-ui/doctest/failed-doctest-output-windows.stdout

@@ -27,7 +27,7 @@ stderr:
 stderr 1
 stderr 2
 
-thread 'main' panicked at $DIR/failed-doctest-output-windows.rs:7:1:
+thread 'main' ($TID) panicked at $DIR/failed-doctest-output-windows.rs:7:1:
 oh no
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 

tests/rustdoc-ui/doctest/failed-doctest-output.stdout

@@ -27,7 +27,7 @@ stderr:
 stderr 1
 stderr 2
 
-thread 'main' panicked at $DIR/failed-doctest-output.rs:7:1:
+thread 'main' ($TID) panicked at $DIR/failed-doctest-output.rs:7:1:
 oh no
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 

tests/rustdoc-ui/doctest/stdout-and-stderr.stdout

@@ -14,7 +14,7 @@ stdout:
 
 stderr:
 
-thread 'main' panicked at $TMP:7:1:
+thread 'main' ($TID) panicked at $TMP:7:1:
 assertion `left == right` failed
   left: "doc"
  right: "test"
@@ -26,7 +26,7 @@ Test executable failed (exit status: 101).
 
 stderr:
 
-thread 'main' panicked at $TMP:15:1:
+thread 'main' ($TID) panicked at $TMP:15:1:
 assertion `left == right` failed
   left: "doc"
  right: "test"

tests/rustdoc-ui/remap-path-prefix-failed-doctest-output.stdout

@@ -9,7 +9,7 @@ Test executable failed (exit status: 101).
 
 stderr:
 
-thread 'main' panicked at remapped_path/remap-path-prefix-failed-doctest-output.rs:3:1:
+thread 'main' ($TID) panicked at remapped_path/remap-path-prefix-failed-doctest-output.rs:3:1:
 oh no
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 

tests/ui/async-await/issues/issue-65419/issue-65419-async-fn-resume-after-completion.rs

@@ -2,7 +2,7 @@
 // be talking about `async fn`s instead.
 
 //@ run-fail
-//@ error-pattern: thread 'main' panicked
+//@ regex-error-pattern: thread 'main'.*panicked
 //@ error-pattern: `async fn` resumed after completion
 //@ edition:2018
 

tests/ui/async-await/issues/issue-65419/issue-65419-async-fn-resume-after-panic.rs

@@ -3,7 +3,7 @@
 
 //@ run-fail
 //@ needs-unwind
-//@ error-pattern: thread 'main' panicked
+//@ regex-error-pattern: thread 'main'.*panicked
 //@ error-pattern: `async fn` resumed after panicking
 //@ edition:2018
 

tests/ui/backtrace/synchronized-panic-handler.run.stderr

@@ -1,7 +1,7 @@
 
-thread '<unnamed>' panicked at $DIR/synchronized-panic-handler.rs:11:5:
+thread '<unnamed>' ($TID) panicked at $DIR/synchronized-panic-handler.rs:11:5:
 oops oh no woe is me
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 
-thread '<unnamed>' panicked at $DIR/synchronized-panic-handler.rs:11:5:
+thread '<unnamed>' ($TID) panicked at $DIR/synchronized-panic-handler.rs:11:5:
 oops oh no woe is me

tests/ui/const-generics/generic_const_exprs/issue-80742.rs

@@ -2,7 +2,7 @@
 //@ known-bug: #97477
 //@ failure-status: 101
 //@ normalize-stderr: "note: .*\n\n" -> ""
-//@ normalize-stderr: "thread 'rustc' panicked.*\n" -> ""
+//@ normalize-stderr: "thread 'rustc'.*panicked.*\n" -> ""
 //@ normalize-stderr: "(error: internal compiler error: [^:]+):\d+:\d+: " -> "$1:LL:CC: "
 //@ rustc-env:RUST_BACKTRACE=0
 

tests/ui/extern/extern-types-field-offset.run.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at library/core/src/panicking.rs:$LINE:$COL:
+thread 'main' ($TID) panicked at library/core/src/panicking.rs:$LINE:$COL:
 attempted to compute the size or alignment of extern type `Opaque`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 thread caused non-unwinding panic. aborting.

tests/ui/extern/extern-types-size_of_val.align.run.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at library/core/src/panicking.rs:$LINE:$COL:
+thread 'main' ($TID) panicked at library/core/src/panicking.rs:$LINE:$COL:
 attempted to compute the size or alignment of extern type `A`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 thread caused non-unwinding panic. aborting.

tests/ui/extern/extern-types-size_of_val.size.run.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at library/core/src/panicking.rs:$LINE:$COL:
+thread 'main' ($TID) panicked at library/core/src/panicking.rs:$LINE:$COL:
 attempted to compute the size or alignment of extern type `A`
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 thread caused non-unwinding panic. aborting.

tests/ui/hygiene/panic-location.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at $DIR/panic-location.rs:LL:CC:
+thread 'main' ($TID) panicked at $DIR/panic-location.rs:LL:CC:
 capacity overflow
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/intrinsics/const-eval-select-backtrace-std.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at $DIR/const-eval-select-backtrace-std.rs:6:8:
+thread 'main' ($TID) panicked at $DIR/const-eval-select-backtrace-std.rs:6:8:
 byte index 1 is out of bounds of ``
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/intrinsics/const-eval-select-backtrace.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at $DIR/const-eval-select-backtrace.rs:15:5:
+thread 'main' ($TID) panicked at $DIR/const-eval-select-backtrace.rs:15:5:
 Aaah!
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/intrinsics/not-overridden.rs

@@ -4,7 +4,7 @@
 //@ build-fail
 //@ failure-status:101
 //@ normalize-stderr: ".*note: .*\n\n" -> ""
-//@ normalize-stderr: "thread 'rustc' panicked.*:\n.*\n" -> ""
+//@ normalize-stderr: "thread 'rustc'.*panicked.*:\n.*\n" -> ""
 //@ normalize-stderr: "internal compiler error:.*: intrinsic const_deallocate " -> ""
 //@ rustc-env:RUST_BACKTRACE=0
 

tests/ui/issues/issue-87707.run.stderr

@@ -1,7 +1,7 @@
 
-thread 'main' panicked at $DIR/issue-87707.rs:14:24:
+thread 'main' ($TID) panicked at $DIR/issue-87707.rs:14:24:
 Here Once instance is poisoned.
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 
-thread 'main' panicked at $DIR/issue-87707.rs:16:7:
+thread 'main' ($TID) panicked at $DIR/issue-87707.rs:16:7:
 Once instance has previously been poisoned

tests/ui/layout/valid_range_oob.rs

@@ -1,6 +1,6 @@
 //@ failure-status: 101
 //@ normalize-stderr: "note: .*\n\n" -> ""
-//@ normalize-stderr: "thread 'rustc' panicked.*\n" -> ""
+//@ normalize-stderr: "thread 'rustc'.*panicked.*\n" -> ""
 //@ rustc-env:RUST_BACKTRACE=0
 
 #![feature(rustc_attrs)]

tests/ui/macros/assert-long-condition.run.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at $DIR/assert-long-condition.rs:7:5:
+thread 'main' ($TID) panicked at $DIR/assert-long-condition.rs:7:5:
 assertion failed: 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 + 11 + 12 + 13 + 14 + 15 + 16 + 17 + 18
                                 + 19 + 20 + 21 + 22 + 23 + 24 + 25 == 0
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/mir/lint/storage-live.rs

@@ -1,7 +1,7 @@
 //@ compile-flags: -Zlint-mir -Ztreat-err-as-bug
 //@ failure-status: 101
 //@ normalize-stderr: "note: .*\n\n" -> ""
-//@ normalize-stderr: "thread 'rustc' panicked.*\n" -> ""
+//@ normalize-stderr: "thread 'rustc'.*panicked.*\n" -> ""
 //@ normalize-stderr: "storage_live\[....\]" -> "storage_live[HASH]"
 //@ normalize-stderr: "(delayed at [^:]+):\d+:\d+ - " -> "$1:LL:CC - "
 //@ rustc-env:RUST_BACKTRACE=0

tests/ui/nll/issue-51345-2.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:explicit panic
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: explicit panic
 //@ needs-subprocess
 
 fn main() {

tests/ui/numbers-arithmetic/overflowing-add.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:attempt to add with overflow
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: attempt to add with overflow
 //@ compile-flags: -C debug-assertions
 //@ needs-subprocess
 

tests/ui/numbers-arithmetic/overflowing-mul.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:attempt to multiply with overflow
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: attempt to multiply with overflow
 //@ needs-subprocess
 //@ compile-flags: -C debug-assertions
 

tests/ui/numbers-arithmetic/overflowing-pow-signed.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:attempt to multiply with overflow
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: attempt to multiply with overflow
 //@ needs-subprocess
 //@ compile-flags: -C debug-assertions
 

tests/ui/numbers-arithmetic/overflowing-pow-unsigned.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:attempt to multiply with overflow
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: attempt to multiply with overflow
 //@ needs-subprocess
 //@ compile-flags: -C debug-assertions
 

tests/ui/numbers-arithmetic/overflowing-sub.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:attempt to subtract with overflow
+//@ regex-error-pattern: thread 'main'.*panicked
+//@ error-pattern: attempt to subtract with overflow
 //@ needs-subprocess
 //@ compile-flags: -C debug-assertions
 

tests/ui/panics/fmt-only-once.run.stderr

@@ -1,5 +1,5 @@
 fmt
 
-thread 'main' panicked at $DIR/fmt-only-once.rs:20:5:
+thread 'main' ($TID) panicked at $DIR/fmt-only-once.rs:20:5:
 PrintOnFmt
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/issue-47429-short-backtraces.run.stderr

@@ -1,5 +1,5 @@
 
-thread 'main' panicked at $DIR/issue-47429-short-backtraces.rs:24:5:
+thread 'main' ($TID) panicked at $DIR/issue-47429-short-backtraces.rs:24:5:
 explicit panic
 stack backtrace:
    0: std::panicking::begin_panic

tests/ui/panics/location-detail-panic-no-column.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at $DIR/location-detail-panic-no-column.rs:7:0:
+thread 'main' ($TID) panicked at $DIR/location-detail-panic-no-column.rs:7:0:
 column-redacted
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/location-detail-panic-no-file.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at <redacted>:7:5:
+thread 'main' ($TID) panicked at <redacted>:7:5:
 file-redacted
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/location-detail-panic-no-line.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at $DIR/location-detail-panic-no-line.rs:0:5:
+thread 'main' ($TID) panicked at $DIR/location-detail-panic-no-line.rs:0:5:
 line-redacted
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/location-detail-panic-no-location-info.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at <redacted>:0:0:
+thread 'main' ($TID) panicked at <redacted>:0:0:
 no location info
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/location-detail-unwrap-no-file.run.stderr

@@ -1,4 +1,4 @@
 
-thread 'main' panicked at <redacted>:8:9:
+thread 'main' ($TID) panicked at <redacted>:8:9:
 called `Option::unwrap()` on a `None` value
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

tests/ui/panics/main-panic.rs

@@ -1,5 +1,5 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked at
+//@ regex-error-pattern: thread 'main' \(\d+\) panicked at
 //@ needs-subprocess
 
 fn main() {

tests/ui/panics/panic-in-cleanup.run.stderr

@@ -1,12 +1,12 @@
 
-thread 'main' panicked at $DIR/panic-in-cleanup.rs:22:5:
+thread 'main' ($TID) panicked at $DIR/panic-in-cleanup.rs:22:5:
 explicit panic
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 
-thread 'main' panicked at $DIR/panic-in-cleanup.rs:16:9:
+thread 'main' ($TID) panicked at $DIR/panic-in-cleanup.rs:16:9:
 BOOM
 stack backtrace:
 
-thread 'main' panicked at library/core/src/panicking.rs:$LINE:$COL:
+thread 'main' ($TID) panicked at library/core/src/panicking.rs:$LINE:$COL:
 panic in a destructor during cleanup
 thread caused non-unwinding panic. aborting.

tests/ui/panics/panic-in-ffi.run.stderr

@@ -1,10 +1,10 @@
 
-thread 'main' panicked at $DIR/panic-in-ffi.rs:21:5:
+thread 'main' ($TID) panicked at $DIR/panic-in-ffi.rs:21:5:
 Test
 note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
 Noisy Drop
 
-thread 'main' panicked at library/core/src/panicking.rs:$LINE:$COL:
+thread 'main' ($TID) panicked at library/core/src/panicking.rs:$LINE:$COL:
 panic in a function that cannot unwind
 stack backtrace:
 thread caused non-unwinding panic. aborting.

tests/ui/panics/panic-set-unset-handler.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:foobar
+//@ regex-error-pattern: thread 'main' \(\d+\) panicked
+//@ error-pattern: foobar
 //@ needs-subprocess
 
 use std::panic;

tests/ui/panics/panic-short-backtrace-windows-x86_64.run.stderr

@@ -1,4 +1,4 @@
-thread 'main' panicked at 'd was called', $DIR/panic-short-backtrace-windows-x86_64.rs:48:5
+thread 'main' ($TID) panicked at 'd was called', $DIR/panic-short-backtrace-windows-x86_64.rs:48:5
 stack backtrace:
    0: std::panicking::begin_panic
    1: d

tests/ui/panics/panic-take-handler-nop.rs

@@ -1,6 +1,6 @@
 //@ run-fail
-//@ error-pattern:thread 'main' panicked
-//@ error-pattern:foobar
+//@ regex-error-pattern: thread 'main' \(\d+\) panicked
+//@ error-pattern: foobar
 //@ needs-subprocess
 
 use std::panic;