diff --git a/src/ci/docker/wasm32-unknown/Dockerfile b/src/ci/docker/wasm32-unknown/Dockerfile index 853923ad947cd..56eda5480715b 100644 --- a/src/ci/docker/wasm32-unknown/Dockerfile +++ b/src/ci/docker/wasm32-unknown/Dockerfile @@ -25,6 +25,12 @@ ENV RUST_CONFIGURE_ARGS \ --set build.nodejs=/node-v9.2.0-linux-x64/bin/node \ --set rust.lld +# Some run-make tests have assertions about code size, and enabling debug +# assertions in libstd causes the binary to be much bigger than it would +# otherwise normally be. We already test libstd with debug assertions in lots of +# other contexts as well +ENV NO_DEBUG_ASSERTIONS=1 + ENV SCRIPT python2.7 /checkout/x.py test --target $TARGETS \ src/test/run-make \ src/test/ui \ diff --git a/src/liballoc/raw_vec.rs b/src/liballoc/raw_vec.rs index 214cc7d7d0cd9..ae933f937c462 100644 --- a/src/liballoc/raw_vec.rs +++ b/src/liballoc/raw_vec.rs @@ -85,8 +85,8 @@ impl RawVec { unsafe { let elem_size = mem::size_of::(); - let alloc_size = cap.checked_mul(elem_size).expect("capacity overflow"); - alloc_guard(alloc_size).expect("capacity overflow"); + let alloc_size = cap.checked_mul(elem_size).unwrap_or_else(|| capacity_overflow()); + alloc_guard(alloc_size).unwrap_or_else(|_| capacity_overflow()); // handles ZSTs and `cap = 0` alike let ptr = if alloc_size == 0 { @@ -309,7 +309,7 @@ impl RawVec { // `from_size_align_unchecked`. let new_cap = 2 * self.cap; let new_size = new_cap * elem_size; - alloc_guard(new_size).expect("capacity overflow"); + alloc_guard(new_size).unwrap_or_else(|_| capacity_overflow()); let ptr_res = self.a.realloc(NonNull::from(self.ptr).as_opaque(), cur, new_size); @@ -368,7 +368,7 @@ impl RawVec { // overflow and the alignment is sufficiently small. let new_cap = 2 * self.cap; let new_size = new_cap * elem_size; - alloc_guard(new_size).expect("capacity overflow"); + alloc_guard(new_size).unwrap_or_else(|_| capacity_overflow()); match self.a.grow_in_place(NonNull::from(self.ptr).as_opaque(), old_layout, new_size) { Ok(_) => { // We can't directly divide `size`. @@ -440,7 +440,7 @@ impl RawVec { pub fn reserve_exact(&mut self, used_cap: usize, needed_extra_cap: usize) { match self.try_reserve_exact(used_cap, needed_extra_cap) { - Err(CapacityOverflow) => panic!("capacity overflow"), + Err(CapacityOverflow) => capacity_overflow(), Err(AllocErr) => self.a.oom(), Ok(()) => { /* yay */ } } @@ -550,7 +550,7 @@ impl RawVec { /// The same as try_reserve, but errors are lowered to a call to oom(). pub fn reserve(&mut self, used_cap: usize, needed_extra_cap: usize) { match self.try_reserve(used_cap, needed_extra_cap) { - Err(CapacityOverflow) => panic!("capacity overflow"), + Err(CapacityOverflow) => capacity_overflow(), Err(AllocErr) => self.a.oom(), Ok(()) => { /* yay */ } } @@ -591,7 +591,7 @@ impl RawVec { } let new_cap = self.amortized_new_size(used_cap, needed_extra_cap) - .expect("capacity overflow"); + .unwrap_or_else(|_| capacity_overflow()); // Here, `cap < used_cap + needed_extra_cap <= new_cap` // (regardless of whether `self.cap - used_cap` wrapped). @@ -599,7 +599,7 @@ impl RawVec { let new_layout = Layout::new::().repeat(new_cap).unwrap().0; // FIXME: may crash and burn on over-reserve - alloc_guard(new_layout.size()).expect("capacity overflow"); + alloc_guard(new_layout.size()).unwrap_or_else(|_| capacity_overflow()); match self.a.grow_in_place( NonNull::from(self.ptr).as_opaque(), old_layout, new_layout.size(), ) { @@ -731,6 +731,13 @@ fn alloc_guard(alloc_size: usize) -> Result<(), CollectionAllocErr> { } } +// One central function responsible for reporting capacity overflows. This'll +// ensure that the code generation related to these panics is minimal as there's +// only one location which panics rather than a bunch throughout the module. +fn capacity_overflow() -> ! { + panic!("capacity overflow") +} + #[cfg(test)] mod tests { use super::*; diff --git a/src/libcore/fmt/mod.rs b/src/libcore/fmt/mod.rs index d55219d7226e6..277bef2bf661a 100644 --- a/src/libcore/fmt/mod.rs +++ b/src/libcore/fmt/mod.rs @@ -1212,7 +1212,11 @@ impl<'a> Formatter<'a> { // truncation. However other flags like `fill`, `width` and `align` // must act as always. if let Some((i, _)) = s.char_indices().skip(max).next() { - &s[..i] + // LLVM here can't prove that `..i` won't panic `&s[..i]`, but + // we know that it can't panic. Use `get` + `unwrap_or` to avoid + // `unsafe` and otherwise don't emit any panic-related code + // here. + s.get(..i).unwrap_or(&s) } else { &s } diff --git a/src/libcore/panic.rs b/src/libcore/panic.rs index 1720c9d8c6079..27ec4aaac75de 100644 --- a/src/libcore/panic.rs +++ b/src/libcore/panic.rs @@ -49,11 +49,17 @@ impl<'a> PanicInfo<'a> { and related macros", issue = "0")] #[doc(hidden)] - pub fn internal_constructor(payload: &'a (Any + Send), - message: Option<&'a fmt::Arguments<'a>>, + #[inline] + pub fn internal_constructor(message: Option<&'a fmt::Arguments<'a>>, location: Location<'a>) -> Self { - PanicInfo { payload, location, message } + PanicInfo { payload: &(), location, message } + } + + #[doc(hidden)] + #[inline] + pub fn set_payload(&mut self, info: &'a (Any + Send)) { + self.payload = info; } /// Returns the payload associated with the panic. @@ -251,3 +257,13 @@ impl<'a> fmt::Display for Location<'a> { write!(formatter, "{}:{}:{}", self.file, self.line, self.col) } } + +/// An internal trait used by libstd to pass data from libstd to `panic_unwind` +/// and other panic runtimes. Not intended to be stabilized any time soon, do +/// not use. +#[unstable(feature = "std_internals", issue = "0")] +#[doc(hidden)] +pub unsafe trait BoxMeUp { + fn box_me_up(&mut self) -> *mut (Any + Send); + fn get(&mut self) -> &(Any + Send); +} diff --git a/src/libpanic_abort/lib.rs b/src/libpanic_abort/lib.rs index 43c5bbbc618c2..392bf17968fbd 100644 --- a/src/libpanic_abort/lib.rs +++ b/src/libpanic_abort/lib.rs @@ -52,7 +52,7 @@ pub unsafe extern fn __rust_maybe_catch_panic(f: fn(*mut u8), // now hopefully. #[no_mangle] #[rustc_std_internal_symbol] -pub unsafe extern fn __rust_start_panic(_data: usize, _vtable: usize) -> u32 { +pub unsafe extern fn __rust_start_panic(_payload: usize) -> u32 { abort(); #[cfg(any(unix, target_os = "cloudabi"))] diff --git a/src/libpanic_unwind/lib.rs b/src/libpanic_unwind/lib.rs index 9321d6917d156..6c52c0fa10cc0 100644 --- a/src/libpanic_unwind/lib.rs +++ b/src/libpanic_unwind/lib.rs @@ -29,6 +29,7 @@ html_root_url = "https://doc.rust-lang.org/nightly/", issue_tracker_base_url = "https://github.com/rust-lang/rust/issues/")] +#![feature(allocator_api)] #![feature(alloc)] #![feature(core_intrinsics)] #![feature(lang_items)] @@ -36,6 +37,7 @@ #![feature(panic_unwind)] #![feature(raw)] #![feature(staged_api)] +#![feature(std_internals)] #![feature(unwind_attributes)] #![cfg_attr(target_env = "msvc", feature(raw))] @@ -47,9 +49,11 @@ extern crate libc; #[cfg(not(any(target_env = "msvc", all(windows, target_arch = "x86_64", target_env = "gnu"))))] extern crate unwind; +use alloc::boxed::Box; use core::intrinsics; use core::mem; use core::raw; +use core::panic::BoxMeUp; // Rust runtime's startup objects depend on these symbols, so make them public. #[cfg(all(target_os="windows", target_arch = "x86", target_env="gnu"))] @@ -112,9 +116,7 @@ pub unsafe extern "C" fn __rust_maybe_catch_panic(f: fn(*mut u8), // implementation. #[no_mangle] #[unwind(allowed)] -pub unsafe extern "C" fn __rust_start_panic(data: usize, vtable: usize) -> u32 { - imp::panic(mem::transmute(raw::TraitObject { - data: data as *mut (), - vtable: vtable as *mut (), - })) +pub unsafe extern "C" fn __rust_start_panic(payload: usize) -> u32 { + let payload = payload as *mut &mut BoxMeUp; + imp::panic(Box::from_raw((*payload).box_me_up())) } diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs index a34fcb5a7f98b..dd96c57538c79 100644 --- a/src/libstd/lib.rs +++ b/src/libstd/lib.rs @@ -292,6 +292,7 @@ #![feature(rand)] #![feature(raw)] #![feature(rustc_attrs)] +#![feature(std_internals)] #![feature(stdsimd)] #![feature(shrink_to)] #![feature(slice_bytes)] diff --git a/src/libstd/panicking.rs b/src/libstd/panicking.rs index fba3269204e90..24eae6a4c821e 100644 --- a/src/libstd/panicking.rs +++ b/src/libstd/panicking.rs @@ -17,6 +17,8 @@ //! * Executing a panic up to doing the actual implementation //! * Shims around "try" +use core::panic::BoxMeUp; + use io::prelude::*; use any::Any; @@ -27,7 +29,7 @@ use intrinsics; use mem; use ptr; use raw; -use sys::stdio::Stderr; +use sys::stdio::{Stderr, stderr_prints_nothing}; use sys_common::rwlock::RWLock; use sys_common::thread_info; use sys_common::util; @@ -56,7 +58,7 @@ extern { data_ptr: *mut usize, vtable_ptr: *mut usize) -> u32; #[unwind(allowed)] - fn __rust_start_panic(data: usize, vtable: usize) -> u32; + fn __rust_start_panic(payload: usize) -> u32; } #[derive(Copy, Clone)] @@ -177,9 +179,6 @@ fn default_hook(info: &PanicInfo) { }; let location = info.location().unwrap(); // The current implementation always returns Some - let file = location.file(); - let line = location.line(); - let col = location.column(); let msg = match info.payload().downcast_ref::<&'static str>() { Some(s) => *s, @@ -193,8 +192,8 @@ fn default_hook(info: &PanicInfo) { let name = thread.as_ref().and_then(|t| t.name()).unwrap_or(""); let write = |err: &mut ::io::Write| { - let _ = writeln!(err, "thread '{}' panicked at '{}', {}:{}:{}", - name, msg, file, line, col); + let _ = writeln!(err, "thread '{}' panicked at '{}', {}", + name, msg, location); #[cfg(feature = "backtrace")] { @@ -212,15 +211,15 @@ fn default_hook(info: &PanicInfo) { let prev = LOCAL_STDERR.with(|s| s.borrow_mut().take()); match (prev, err.as_mut()) { - (Some(mut stderr), _) => { - write(&mut *stderr); - let mut s = Some(stderr); - LOCAL_STDERR.with(|slot| { - *slot.borrow_mut() = s.take(); - }); - } - (None, Some(ref mut err)) => { write(err) } - _ => {} + (Some(mut stderr), _) => { + write(&mut *stderr); + let mut s = Some(stderr); + LOCAL_STDERR.with(|slot| { + *slot.borrow_mut() = s.take(); + }); + } + (None, Some(ref mut err)) => { write(err) } + _ => {} } } @@ -342,9 +341,38 @@ pub fn begin_panic_fmt(msg: &fmt::Arguments, // panic + OOM properly anyway (see comment in begin_panic // below). - let mut s = String::new(); - let _ = s.write_fmt(*msg); - rust_panic_with_hook(Box::new(s), Some(msg), file_line_col) + rust_panic_with_hook(&mut PanicPayload::new(msg), Some(msg), file_line_col); + + struct PanicPayload<'a> { + inner: &'a fmt::Arguments<'a>, + string: Option, + } + + impl<'a> PanicPayload<'a> { + fn new(inner: &'a fmt::Arguments<'a>) -> PanicPayload<'a> { + PanicPayload { inner, string: None } + } + + fn fill(&mut self) -> &mut String { + let inner = self.inner; + self.string.get_or_insert_with(|| { + let mut s = String::new(); + drop(s.write_fmt(*inner)); + s + }) + } + } + + unsafe impl<'a> BoxMeUp for PanicPayload<'a> { + fn box_me_up(&mut self) -> *mut (Any + Send) { + let contents = mem::replace(self.fill(), String::new()); + Box::into_raw(Box::new(contents)) + } + + fn get(&mut self) -> &(Any + Send) { + self.fill() + } + } } /// This is the entry point of panicking for panic!() and assert!(). @@ -360,18 +388,42 @@ pub fn begin_panic(msg: M, file_line_col: &(&'static str, u32, u3 // be performed in the parent of this thread instead of the thread that's // panicking. - rust_panic_with_hook(Box::new(msg), None, file_line_col) + rust_panic_with_hook(&mut PanicPayload::new(msg), None, file_line_col); + + struct PanicPayload { + inner: Option, + } + + impl PanicPayload { + fn new(inner: A) -> PanicPayload { + PanicPayload { inner: Some(inner) } + } + } + + unsafe impl BoxMeUp for PanicPayload { + fn box_me_up(&mut self) -> *mut (Any + Send) { + let data = match self.inner.take() { + Some(a) => Box::new(a) as Box, + None => Box::new(()), + }; + Box::into_raw(data) + } + + fn get(&mut self) -> &(Any + Send) { + match self.inner { + Some(ref a) => a, + None => &(), + } + } + } } -/// Executes the primary logic for a panic, including checking for recursive -/// panics and panic hooks. +/// Central point for dispatching panics. /// -/// This is the entry point or panics from libcore, formatted panics, and -/// `Box` panics. Here we'll verify that we're not panicking recursively, -/// run panic hooks, and then delegate to the actual implementation of panics. -#[inline(never)] -#[cold] -fn rust_panic_with_hook(payload: Box, +/// Executes the primary logic for a panic, including checking for recursive +/// panics, panic hooks, and finally dispatching to the panic runtime to either +/// abort or unwind. +fn rust_panic_with_hook(payload: &mut BoxMeUp, message: Option<&fmt::Arguments>, file_line_col: &(&'static str, u32, u32)) -> ! { let (file, line, col) = *file_line_col; @@ -390,15 +442,24 @@ fn rust_panic_with_hook(payload: Box, } unsafe { - let info = PanicInfo::internal_constructor( - &*payload, + let mut info = PanicInfo::internal_constructor( message, Location::internal_constructor(file, line, col), ); HOOK_LOCK.read(); match HOOK { - Hook::Default => default_hook(&info), - Hook::Custom(ptr) => (*ptr)(&info), + // Some platforms know that printing to stderr won't ever actually + // print anything, and if that's the case we can skip the default + // hook. + Hook::Default if stderr_prints_nothing() => {} + Hook::Default => { + info.set_payload(payload.get()); + default_hook(&info); + } + Hook::Custom(ptr) => { + info.set_payload(payload.get()); + (*ptr)(&info); + } } HOOK_LOCK.read_unlock(); } @@ -419,16 +480,29 @@ fn rust_panic_with_hook(payload: Box, /// Shim around rust_panic. Called by resume_unwind. pub fn update_count_then_panic(msg: Box) -> ! { update_panic_count(1); - rust_panic(msg) + + struct RewrapBox(Box); + + unsafe impl BoxMeUp for RewrapBox { + fn box_me_up(&mut self) -> *mut (Any + Send) { + Box::into_raw(mem::replace(&mut self.0, Box::new(()))) + } + + fn get(&mut self) -> &(Any + Send) { + &*self.0 + } + } + + rust_panic(&mut RewrapBox(msg)) } /// A private no-mangle function on which to slap yer breakpoints. #[no_mangle] #[allow(private_no_mangle_fns)] // yes we get it, but we like breakpoints -pub fn rust_panic(msg: Box) -> ! { +pub fn rust_panic(mut msg: &mut BoxMeUp) -> ! { let code = unsafe { - let obj = mem::transmute::<_, raw::TraitObject>(msg); - __rust_start_panic(obj.data as usize, obj.vtable as usize) + let obj = &mut msg as *mut &mut BoxMeUp; + __rust_start_panic(obj as usize) }; rtabort!("failed to initiate panic, error {}", code) } diff --git a/src/libstd/sys/cloudabi/stdio.rs b/src/libstd/sys/cloudabi/stdio.rs index 9519a92647108..1d7344f921c9d 100644 --- a/src/libstd/sys/cloudabi/stdio.rs +++ b/src/libstd/sys/cloudabi/stdio.rs @@ -77,3 +77,7 @@ pub fn is_ebadf(err: &io::Error) -> bool { } pub const STDIN_BUF_SIZE: usize = ::sys_common::io::DEFAULT_BUF_SIZE; + +pub fn stderr_prints_nothing() -> bool { + false +} diff --git a/src/libstd/sys/redox/stdio.rs b/src/libstd/sys/redox/stdio.rs index 3abb094ac34e3..7a4d11b0ecb9a 100644 --- a/src/libstd/sys/redox/stdio.rs +++ b/src/libstd/sys/redox/stdio.rs @@ -75,3 +75,7 @@ pub fn is_ebadf(err: &io::Error) -> bool { } pub const STDIN_BUF_SIZE: usize = ::sys_common::io::DEFAULT_BUF_SIZE; + +pub fn stderr_prints_nothing() -> bool { + false +} diff --git a/src/libstd/sys/unix/stdio.rs b/src/libstd/sys/unix/stdio.rs index e9b3d4affc7dd..87ba2aef4f1d3 100644 --- a/src/libstd/sys/unix/stdio.rs +++ b/src/libstd/sys/unix/stdio.rs @@ -75,3 +75,7 @@ pub fn is_ebadf(err: &io::Error) -> bool { } pub const STDIN_BUF_SIZE: usize = ::sys_common::io::DEFAULT_BUF_SIZE; + +pub fn stderr_prints_nothing() -> bool { + false +} diff --git a/src/libstd/sys/wasm/rwlock.rs b/src/libstd/sys/wasm/rwlock.rs index 8b06f54167487..6516010af4759 100644 --- a/src/libstd/sys/wasm/rwlock.rs +++ b/src/libstd/sys/wasm/rwlock.rs @@ -30,7 +30,7 @@ impl RWLock { if *mode >= 0 { *mode += 1; } else { - panic!("rwlock locked for writing"); + rtabort!("rwlock locked for writing"); } } @@ -51,7 +51,7 @@ impl RWLock { if *mode == 0 { *mode = -1; } else { - panic!("rwlock locked for reading") + rtabort!("rwlock locked for reading") } } diff --git a/src/libstd/sys/wasm/stdio.rs b/src/libstd/sys/wasm/stdio.rs index beb19c0ed2c1f..023f29576a27d 100644 --- a/src/libstd/sys/wasm/stdio.rs +++ b/src/libstd/sys/wasm/stdio.rs @@ -69,3 +69,7 @@ pub const STDIN_BUF_SIZE: usize = 0; pub fn is_ebadf(_err: &io::Error) -> bool { true } + +pub fn stderr_prints_nothing() -> bool { + !cfg!(feature = "wasm_syscall") +} diff --git a/src/libstd/sys/windows/stdio.rs b/src/libstd/sys/windows/stdio.rs index b43df20bddd08..81b89da21d3c6 100644 --- a/src/libstd/sys/windows/stdio.rs +++ b/src/libstd/sys/windows/stdio.rs @@ -227,3 +227,7 @@ pub fn is_ebadf(err: &io::Error) -> bool { // idea is that on windows we use a slightly smaller buffer that's // been seen to be acceptable. pub const STDIN_BUF_SIZE: usize = 8 * 1024; + +pub fn stderr_prints_nothing() -> bool { + false +} diff --git a/src/libstd/sys_common/backtrace.rs b/src/libstd/sys_common/backtrace.rs index 1955f3ec9a28f..20109d2d0d5ac 100644 --- a/src/libstd/sys_common/backtrace.rs +++ b/src/libstd/sys_common/backtrace.rs @@ -139,10 +139,10 @@ pub fn __rust_begin_short_backtrace(f: F) -> T /// Controls how the backtrace should be formatted. #[derive(Debug, Copy, Clone, Eq, PartialEq)] pub enum PrintFormat { - /// Show all the frames with absolute path for files. - Full = 2, /// Show only relevant data from the backtrace. - Short = 3, + Short = 2, + /// Show all the frames with absolute path for files. + Full = 3, } // For now logging is turned off by default, and this function checks to see @@ -150,11 +150,10 @@ pub enum PrintFormat { pub fn log_enabled() -> Option { static ENABLED: atomic::AtomicIsize = atomic::AtomicIsize::new(0); match ENABLED.load(Ordering::SeqCst) { - 0 => {}, + 0 => {} 1 => return None, - 2 => return Some(PrintFormat::Full), - 3 => return Some(PrintFormat::Short), - _ => unreachable!(), + 2 => return Some(PrintFormat::Short), + _ => return Some(PrintFormat::Full), } let val = match env::var_os("RUST_BACKTRACE") { diff --git a/src/libstd/sys_common/mod.rs b/src/libstd/sys_common/mod.rs index 27504d374ddbf..d0c4d6a773746 100644 --- a/src/libstd/sys_common/mod.rs +++ b/src/libstd/sys_common/mod.rs @@ -28,6 +28,16 @@ use sync::Once; use sys; +macro_rules! rtabort { + ($($t:tt)*) => (::sys_common::util::abort(format_args!($($t)*))) +} + +macro_rules! rtassert { + ($e:expr) => (if !$e { + rtabort!(concat!("assertion failed: ", stringify!($e))); + }) +} + pub mod at_exit_imp; #[cfg(feature = "backtrace")] pub mod backtrace; @@ -101,10 +111,6 @@ pub fn at_exit(f: F) -> Result<(), ()> { if at_exit_imp::push(Box::new(f)) {Ok(())} else {Err(())} } -macro_rules! rtabort { - ($($t:tt)*) => (::sys_common::util::abort(format_args!($($t)*))) -} - /// One-time runtime cleanup. pub fn cleanup() { static CLEANUP: Once = Once::new(); diff --git a/src/libstd/sys_common/thread_local.rs b/src/libstd/sys_common/thread_local.rs index a4aa3d96d25c0..d0d6224de0a15 100644 --- a/src/libstd/sys_common/thread_local.rs +++ b/src/libstd/sys_common/thread_local.rs @@ -169,7 +169,7 @@ impl StaticKey { self.key.store(key, Ordering::SeqCst); } INIT_LOCK.unlock(); - assert!(key != 0); + rtassert!(key != 0); return key } @@ -190,7 +190,7 @@ impl StaticKey { imp::destroy(key1); key2 }; - assert!(key != 0); + rtassert!(key != 0); match self.key.compare_and_swap(0, key as usize, Ordering::SeqCst) { // The CAS succeeded, so we've created the actual key 0 => key as usize, diff --git a/src/libstd/sys_common/util.rs b/src/libstd/sys_common/util.rs index a391c7cc6ef0c..a373e980b970d 100644 --- a/src/libstd/sys_common/util.rs +++ b/src/libstd/sys_common/util.rs @@ -10,10 +10,13 @@ use fmt; use io::prelude::*; -use sys::stdio::Stderr; +use sys::stdio::{Stderr, stderr_prints_nothing}; use thread; pub fn dumb_print(args: fmt::Arguments) { + if stderr_prints_nothing() { + return + } let _ = Stderr::new().map(|mut stderr| stderr.write_fmt(args)); } diff --git a/src/libstd/thread/local.rs b/src/libstd/thread/local.rs index 99479bc56eff3..40d3280baa687 100644 --- a/src/libstd/thread/local.rs +++ b/src/libstd/thread/local.rs @@ -172,12 +172,16 @@ macro_rules! __thread_local_inner { &'static $crate::cell::UnsafeCell< $crate::option::Option<$t>>> { + #[cfg(target_arch = "wasm32")] + static __KEY: $crate::thread::__StaticLocalKeyInner<$t> = + $crate::thread::__StaticLocalKeyInner::new(); + #[thread_local] - #[cfg(target_thread_local)] + #[cfg(all(target_thread_local, not(target_arch = "wasm32")))] static __KEY: $crate::thread::__FastLocalKeyInner<$t> = $crate::thread::__FastLocalKeyInner::new(); - #[cfg(not(target_thread_local))] + #[cfg(all(not(target_thread_local), not(target_arch = "wasm32")))] static __KEY: $crate::thread::__OsLocalKeyInner<$t> = $crate::thread::__OsLocalKeyInner::new(); @@ -295,6 +299,39 @@ impl LocalKey { } } +/// On some platforms like wasm32 there's no threads, so no need to generate +/// thread locals and we can instead just use plain statics! +#[doc(hidden)] +#[cfg(target_arch = "wasm32")] +pub mod statik { + use cell::UnsafeCell; + use fmt; + + pub struct Key { + inner: UnsafeCell>, + } + + unsafe impl ::marker::Sync for Key { } + + impl fmt::Debug for Key { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + f.pad("Key { .. }") + } + } + + impl Key { + pub const fn new() -> Key { + Key { + inner: UnsafeCell::new(None), + } + } + + pub unsafe fn get(&self) -> Option<&'static UnsafeCell>> { + Some(&*(&self.inner as *const _)) + } + } +} + #[doc(hidden)] #[cfg(target_thread_local)] pub mod fast { diff --git a/src/libstd/thread/mod.rs b/src/libstd/thread/mod.rs index 71aee673cfe3e..1b976b79b4c98 100644 --- a/src/libstd/thread/mod.rs +++ b/src/libstd/thread/mod.rs @@ -202,6 +202,9 @@ pub use self::local::{LocalKey, AccessError}; // where fast TLS was not available; end-user code is compiled with fast TLS // where available, but both are needed. +#[unstable(feature = "libstd_thread_internals", issue = "0")] +#[cfg(target_arch = "wasm32")] +#[doc(hidden)] pub use self::local::statik::Key as __StaticLocalKeyInner; #[unstable(feature = "libstd_thread_internals", issue = "0")] #[cfg(target_thread_local)] #[doc(hidden)] pub use self::local::fast::Key as __FastLocalKeyInner; diff --git a/src/test/run-make/wasm-panic-small/Makefile b/src/test/run-make/wasm-panic-small/Makefile new file mode 100644 index 0000000000000..330ae300c445e --- /dev/null +++ b/src/test/run-make/wasm-panic-small/Makefile @@ -0,0 +1,17 @@ +-include ../../run-make-fulldeps/tools.mk + +ifeq ($(TARGET),wasm32-unknown-unknown) +all: + $(RUSTC) foo.rs -C lto -O --target wasm32-unknown-unknown --cfg a + wc -c < $(TMPDIR)/foo.wasm + [ "`wc -c < $(TMPDIR)/foo.wasm`" -lt "1024" ] + $(RUSTC) foo.rs -C lto -O --target wasm32-unknown-unknown --cfg b + wc -c < $(TMPDIR)/foo.wasm + [ "`wc -c < $(TMPDIR)/foo.wasm`" -lt "5120" ] + $(RUSTC) foo.rs -C lto -O --target wasm32-unknown-unknown --cfg c + wc -c < $(TMPDIR)/foo.wasm + [ "`wc -c < $(TMPDIR)/foo.wasm`" -lt "5120" ] +else +all: +endif + diff --git a/src/test/run-make/wasm-panic-small/foo.rs b/src/test/run-make/wasm-panic-small/foo.rs new file mode 100644 index 0000000000000..1ea724ca94d47 --- /dev/null +++ b/src/test/run-make/wasm-panic-small/foo.rs @@ -0,0 +1,29 @@ +// Copyright 2018 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![crate_type = "cdylib"] + +#[no_mangle] +#[cfg(a)] +pub fn foo() { + panic!("test"); +} + +#[no_mangle] +#[cfg(b)] +pub fn foo() { + panic!("{}", 1); +} + +#[no_mangle] +#[cfg(c)] +pub fn foo() { + panic!("{}", "a"); +}