Run Miri on CI

.github/workflows/ci.yml

@@ -125,6 +125,15 @@ jobs:
       - name: clippy
         run: ./ci/clippy.sh
 
+  # Run miri.
+  miri:
+    name: miri
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: miri
+        run: ./ci/miri.sh
+
   # Run sanitizers.
   san:
     name: san
@@ -174,6 +183,7 @@ jobs:
       - codegen
       - rustfmt
       - clippy
+      - miri
       - san
       - loom
       - docs

ci/miri.sh

@@ -0,0 +1,54 @@
+#!/bin/bash
+
+cd "$(dirname "$0")"/..
+set -ex
+
+toolchain=nightly-$(curl -s https://rust-lang.github.io/rustup-components-history/x86_64-unknown-linux-gnu/miri)
+rustup set profile minimal
+rustup default "$toolchain"
+rustup component add miri
+
+MIRIFLAGS="-Zmiri-tag-raw-pointers -Zmiri-disable-isolation" \
+    cargo miri test \
+        -p crossbeam-utils \
+        -p crossbeam-queue
+
+# -Zmiri-ignore-leaks is needed because we use detached threads in tests/docs: https://github.com/rust-lang/miri/issues/1371
+# When enable -Zmiri-tag-raw-pointers, the following error is reported:
+# error: Undefined Behavior: trying to reborrow for SharedReadWrite at alloc3637744, but parent tag <untagged> does not have an appropriate item in the borrow stack
+#     --> /Users/taiki/projects/crossbeam/crossbeam-channel/src/flavors/zero.rs:137:22
+#      |
+# 137  |         let packet = &*(token.zero as *const Packet<T>);
+#      |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ trying to reborrow for SharedReadWrite at alloc3637744, but parent tag <untagged> does not have an appropriate item in the borrow stack
+#      |
+#      = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+#      = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
+#
+#      = note: inside `crossbeam_channel::flavors::zero::Channel::<i32>::write` at /Users/taiki/projects/crossbeam/crossbeam-channel/src/flavors/zero.rs:137:22
+#      = note: inside `crossbeam_channel::flavors::zero::Channel::<i32>::send` at /Users/taiki/projects/crossbeam/crossbeam-channel/src/flavors/zero.rs:219:17
+#      = note: inside `crossbeam_channel::Sender::<i32>::send` at /Users/taiki/projects/crossbeam/crossbeam-channel/src/channel.rs:428:41
+# note: inside `SyncSender::<i32>::send` at crossbeam-channel/tests/mpsc.rs:54:9
+#     --> crossbeam-channel/tests/mpsc.rs:54:9
+#      |
+# 54   |         self.inner.send(t).map_err(|cc::SendError(m)| SendError(m))
+#      |         ^^^^^^^^^^^^^^^^^^
+# note: inside closure at crossbeam-channel/tests/mpsc.rs:2097:13
+#     --> crossbeam-channel/tests/mpsc.rs:2097:13
+#      |
+# 2097 |             tx.send(1).unwrap();
+#      |             ^^^^^^^^^^
+MIRIFLAGS="-Zmiri-disable-isolation -Zmiri-ignore-leaks" \
+    cargo miri test \
+        -p crossbeam-channel
+
+# -Zmiri-ignore-leaks is needed for https://github.com/crossbeam-rs/crossbeam/issues/579
+# -Zmiri-disable-stacked-borrows is needed for https://github.com/crossbeam-rs/crossbeam/issues/545
+MIRIFLAGS="-Zmiri-disable-isolation -Zmiri-ignore-leaks -Zmiri-disable-stacked-borrows" \
+    cargo miri test \
+        -p crossbeam-epoch \
+        -p crossbeam-skiplist \
+        -p crossbeam
+
+MIRIFLAGS="-Zmiri-disable-isolation -Zmiri-ignore-leaks -Zmiri-disable-stacked-borrows -Zmiri-compare-exchange-weak-failure-rate=1.0" \
+    cargo miri test \
+        -p crossbeam-deque

crossbeam-channel/src/flavors/array.rs

@@ -10,7 +10,7 @@
 
 use std::cell::UnsafeCell;
 use std::marker::PhantomData;
-use std::mem::{self, MaybeUninit};
+use std::mem::MaybeUninit;
 use std::ptr;
 use std::sync::atomic::{self, AtomicUsize, Ordering};
 use std::time::Instant;
@@ -110,7 +110,7 @@ impl<T> Channel<T> {
         // Allocate a buffer of `cap` slots initialized
         // with stamps.
         let buffer = {
-            let mut boxed: Box<[Slot<T>]> = (0..cap)
+            let boxed: Box<[Slot<T>]> = (0..cap)
                 .map(|i| {
                     // Set the stamp to `{ lap: 0, mark: 0, index: i }`.
                     Slot {
@@ -119,9 +119,7 @@ impl<T> Channel<T> {
                     }
                 })
                 .collect();
-            let ptr = boxed.as_mut_ptr();
-            mem::forget(boxed);
-            ptr
+            Box::into_raw(boxed) as *mut Slot<T>
         };
 
         Channel {

crossbeam-channel/tests/after.rs

@@ -1,5 +1,7 @@
 //! Tests for the after channel flavor.
 
+#![cfg(not(miri))] // TODO: many assertions failed due to Miri is slow
+
 use std::sync::atomic::AtomicUsize;
 use std::sync::atomic::Ordering;
 use std::thread;

crossbeam-channel/tests/array.rs

@@ -1,5 +1,7 @@
 //! Tests for the array channel flavor.
 
+#![cfg(not(miri))] // TODO: many assertions failed due to Miri is slow
+
 use std::any::Any;
 use std::sync::atomic::AtomicUsize;
 use std::sync::atomic::Ordering;

crossbeam-channel/tests/golang.rs

@@ -232,6 +232,9 @@ macro_rules! go {
 mod doubleselect {
     use super::*;
 
+    #[cfg(miri)]
+    const ITERATIONS: i32 = 100;
+    #[cfg(not(miri))]
     const ITERATIONS: i32 = 10_000;
 
     fn sender(n: i32, c1: Chan<i32>, c2: Chan<i32>, c3: Chan<i32>, c4: Chan<i32>) {
@@ -691,6 +694,11 @@ mod select {
 mod select2 {
     use super::*;
 
+    #[cfg(miri)]
+    const N: i32 = 1000;
+    #[cfg(not(miri))]
+    const N: i32 = 100000;
+
     #[test]
     fn main() {
         fn sender(c: &Chan<i32>, n: i32) {
@@ -717,15 +725,18 @@ mod select2 {
 
         ALLOCATED.store(0, SeqCst);
 
-        go!(c, sender(&c, 100000));
-        receiver(&c, &dummy, 100000);
+        go!(c, sender(&c, N));
+        receiver(&c, &dummy, N);
 
         let alloc = ALLOCATED.load(SeqCst);
 
-        go!(c, sender(&c, 100000));
-        receiver(&c, &dummy, 100000);
+        go!(c, sender(&c, N));
+        receiver(&c, &dummy, N);
 
-        assert!(!(ALLOCATED.load(SeqCst) > alloc && (ALLOCATED.load(SeqCst) - alloc) > 110000))
+        assert!(
+            !(ALLOCATED.load(SeqCst) > alloc
+                && (ALLOCATED.load(SeqCst) - alloc) > (N as usize + 10000))
+        )
     }
 }
 
@@ -913,6 +924,9 @@ mod chan_test {
 
     #[test]
     fn test_chan() {
+        #[cfg(miri)]
+        const N: i32 = 20;
+        #[cfg(not(miri))]
         const N: i32 = 200;
 
         for cap in 0..N {
@@ -1052,6 +1066,9 @@ mod chan_test {
 
     #[test]
     fn test_nonblock_recv_race() {
+        #[cfg(miri)]
+        const N: usize = 100;
+        #[cfg(not(miri))]
         const N: usize = 1000;
 
         for _ in 0..N {
@@ -1073,6 +1090,9 @@ mod chan_test {
 
     #[test]
     fn test_nonblock_select_race() {
+        #[cfg(miri)]
+        const N: usize = 100;
+        #[cfg(not(miri))]
         const N: usize = 1000;
 
         let done = make::<bool>(1);
@@ -1106,6 +1126,9 @@ mod chan_test {
 
     #[test]
     fn test_nonblock_select_race2() {
+        #[cfg(miri)]
+        const N: usize = 100;
+        #[cfg(not(miri))]
         const N: usize = 1000;
 
         let done = make::<bool>(1);
@@ -1142,6 +1165,11 @@ mod chan_test {
         // Ensure that send/recv on the same chan in select
         // does not crash nor deadlock.
 
+        #[cfg(miri)]
+        const N: usize = 100;
+        #[cfg(not(miri))]
+        const N: usize = 1000;
+
         for &cap in &[0, 10] {
             let wg = WaitGroup::new();
             wg.add(2);
@@ -1151,7 +1179,7 @@ mod chan_test {
                 let p = p;
                 go!(wg, p, c, {
                     defer! { wg.done() }
-                    for i in 0..1000 {
+                    for i in 0..N {
                         if p == 0 || i % 2 == 0 {
                             select! {
                                 send(c.tx(), p) -> _ => {}
@@ -1180,15 +1208,18 @@ mod chan_test {
 
     #[test]
     fn test_select_stress() {
+        #[cfg(miri)]
+        const N: usize = 100;
+        #[cfg(not(miri))]
+        const N: usize = 10000;
+
         let c = vec![
             make::<i32>(0),
             make::<i32>(0),
             make::<i32>(2),
             make::<i32>(3),
         ];
 
-        const N: usize = 10000;
-
         // There are 4 goroutines that send N values on each of the chans,
         // + 4 goroutines that receive N values on each of the chans,
         // + 1 goroutine that sends N values on each of the chans in a single select,
@@ -1286,6 +1317,9 @@ mod chan_test {
 
     #[test]
     fn test_select_fairness() {
+        #[cfg(miri)]
+        const TRIALS: usize = 100;
+        #[cfg(not(miri))]
         const TRIALS: usize = 10000;
 
         let c1 = make::<u8>(TRIALS + 1);
@@ -1369,6 +1403,9 @@ mod chan_test {
 
     #[test]
     fn test_pseudo_random_send() {
+        #[cfg(miri)]
+        const N: usize = 20;
+        #[cfg(not(miri))]
         const N: usize = 100;
 
         for cap in 0..N {
@@ -1412,6 +1449,9 @@ mod chan_test {
     #[test]
     fn test_multi_consumer() {
         const NWORK: usize = 23;
+        #[cfg(miri)]
+        const NITER: usize = 100;
+        #[cfg(not(miri))]
         const NITER: usize = 271828;
 
         let pn = [2, 3, 7, 11, 13, 17, 19, 23, 27, 31];
@@ -1510,6 +1550,9 @@ mod chan1 {
     use super::*;
 
     // sent messages
+    #[cfg(miri)]
+    const N: usize = 100;
+    #[cfg(not(miri))]
     const N: usize = 1000;
     // receiving "goroutines"
     const M: usize = 10;

crossbeam-channel/tests/list.rs

@@ -239,6 +239,9 @@ fn disconnect_wakes_receiver() {
 
 #[test]
 fn spsc() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 100_000;
 
     let (s, r) = unbounded();
@@ -261,6 +264,9 @@ fn spsc() {
 
 #[test]
 fn mpmc() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 25_000;
     const THREADS: usize = 4;
 
@@ -295,6 +301,9 @@ fn mpmc() {
 
 #[test]
 fn stress_oneshot() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 10_000;
 
     for _ in 0..COUNT {
@@ -310,6 +319,9 @@ fn stress_oneshot() {
 
 #[test]
 fn stress_iter() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 100_000;
 
     let (request_s, request_r) = unbounded();
@@ -371,8 +383,11 @@ fn stress_timeout_two_threads() {
     .unwrap();
 }
 
+#[cfg_attr(miri, ignore)] // Miri is too slow
 #[test]
 fn drops() {
+    const RUNS: usize = 100;
+
     static DROPS: AtomicUsize = AtomicUsize::new(0);
 
     #[derive(Debug, PartialEq)]
@@ -386,7 +401,7 @@ fn drops() {
 
     let mut rng = thread_rng();
 
-    for _ in 0..100 {
+    for _ in 0..RUNS {
         let steps = rng.gen_range(0..10_000);
         let additional = rng.gen_range(0..1000);
 
@@ -421,6 +436,9 @@ fn drops() {
 
 #[test]
 fn linearizable() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 25_000;
     const THREADS: usize = 4;
 
@@ -441,6 +459,9 @@ fn linearizable() {
 
 #[test]
 fn fairness() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 10_000;
 
     let (s1, r1) = unbounded::<()>();
@@ -463,6 +484,9 @@ fn fairness() {
 
 #[test]
 fn fairness_duplicates() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 10_000;
 
     let (s, r) = unbounded();
@@ -496,6 +520,9 @@ fn recv_in_send() {
 
 #[test]
 fn channel_through_channel() {
+    #[cfg(miri)]
+    const COUNT: usize = 100;
+    #[cfg(not(miri))]
     const COUNT: usize = 1000;
 
     type T = Box<dyn Any + Send>;