diff options
Diffstat (limited to 'library/std/src/rt.rs')
| -rw-r--r-- | library/std/src/rt.rs | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/library/std/src/rt.rs b/library/std/src/rt.rs index 0a841f07e3b..80e7c3c026b 100644 --- a/library/std/src/rt.rs +++ b/library/std/src/rt.rs @@ -102,9 +102,24 @@ unsafe fn init(argc: isize, argv: *const *const u8, sigpipe: u8) { sys::init(argc, argv, sigpipe) }; - // Set up the current thread to give it the right name. - let thread = Thread::new_main(); - thread::set_current(thread); + // Set up the current thread handle to give it the right name. + // + // When code running before main uses `ReentrantLock` (for example by + // using `println!`), the thread ID can become initialized before we + // create this handle. Since `set_current` fails when the ID of the + // handle does not match the current ID, we should attempt to use the + // current thread ID here instead of unconditionally creating a new + // one. Also see #130210. + let thread = Thread::new_main(thread::current_id()); + if let Err(_thread) = thread::set_current(thread) { + // `thread::current` will create a new handle if none has been set yet. + // Thus, if someone uses it before main, this call will fail. That's a + // bad idea though, as we then cannot set the main thread name here. + // + // FIXME: detect the main thread in `thread::current` and use the + // correct name there. + rtabort!("code running before main must not use thread::current"); + } } /// Clean up the thread-local runtime state. This *should* be run after all other |