Auto merge of #1617 - JCTyblaidd:data_race_detector, r=RalfJung

Add simple data-race detector

Partially fixes data-race detection, see #1372, based on Dynamic Race Detection for C++11

- This does not explore weak memory behaviour, only exploring one sequentially consistent ordering.
- Data-race detection is only enabled after the first thread is created, so should have minimal overhead for non-concurrent execution.
- ~~Does not attempt to re-use thread id's so creating and joining threads lots of time in an execution will result in the vector clocks growing in size and slowing down program execution~~ It does now

Cargo.toml

@@ -30,6 +30,7 @@ log = "0.4"
 shell-escape = "0.1.4"
 hex = "0.4.0"
 rand = "0.7"
+smallvec = "1.4.2"
 
 # A noop dependency that changes in the Rust repository, it's a bit of a hack.
 # See the `src/tools/rustc-workspace-hack/README.md` file in `rust-lang/rust`

bench-cargo-miri/mse/src/main.rs

@@ -2,6 +2,9 @@ static EXPECTED: &[u8] = &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 static PCM: &[i16] = &[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, -2, 0, -2, 0, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 1, 0, 1, 0, 0, -2, 0, -2, 0, -2, 0, -2, -2, -2, -3, -3, -3, -3, -4, -2, -5, -2, -5, -2, -4, 0, -4, 0, -4, 0, -4, 1, -4, 1, -4, 2, -4, 2, -4, 2, -4, 2, -4, 2, -3, 1, -4, 0, -4, 0, -5, 0, -5, 0, -5, 0, -4, 2, -4, 3, -4, 4, -3, 5, -2, 5, -3, 6, -3, 6, -3, 5, -3, 5, -2, 4, -2, 3, -5, 0, -6, 0, -3, -2, -4, -4, -9, -5, -9, -4, -4, -2, -4, -2, -4, 0, -2, 1, 1, 1, 4, 2, 8, 2, 12, 1, 13, 0, 12, 0, 11, 0, 8, -2, 7, 0, 7, -3, 11, -8, 15, -9, 17, -6, 17, -5, 13, -3, 7, 0, 3, 0, -2, 0, -4, 0, -4, -2, -6, 0, -14, -2, -17, -4, -8, 0, -7, 5, -17, 7, -18, 10, -7, 18, -2, 25, -3, 27, 0, 31, 4, 34, 4, 34, 8, 36, 8, 37, 2, 36, 4, 34, 8, 28, 3, 15, 0, 11, 0, 12, -5, 8, -4, 10, 0, 23, -4, 31, -8, 30, -2, 30, 0, 26, -6, 22, -6, 20, -12, 15, -19, 10, -10, 13, -14, 6, -43, -13, -43, -16, -9, -12, -10, -29, -42, -40, -37, -28, -5, -21, 1, -24, -8, -20, 4, -18, 26, -24, 44, -26, 66, -30, 86, -37, 88, -41, 72, -46, 50, -31, 28, 23, 14, 64, 16, 51, 26, 32, 34, 39, 42, 48, 35, 58, 0, 72, -36, 69, -59, 58, -98, 54, -124, 36, -103, 12, -110, 5, -173, -19, -146, -59, -4, -42, 51, 1, -23, -6, -30, -6, 45, 46, 47, 70, 6, 55, 19, 60, 38, 62, 42, 47, 61, 46, 40, 42, -19, 22, -34, 6, -35, -50, -61, -141, -37, -171, 17, -163, 26, -180, 46, -154, 80, -63, 48, -4, 18, 20, 50, 47, 58, 53, 44, 61, 57, 85, 37, 80, 0, 86, -8, 106, -95, 49, -213, -8, -131, 47, 49, 63, 40, -39, -69, -74, -37, -20, 63, -12, 58, -14, -12, 25, -31, 41, 11, 45, 76, 47, 167, 5, 261, -37, 277, -83, 183, -172, 35, -122, -79, 138, -70, 266, 69, 124, 228, 0, 391, -29, 594, -84, 702, -78, 627, -8, 551, -13, 509, 13, 372, 120, 352, 125, 622, 127, 691, 223, 362, 126, 386, -33, 915, 198, 958, 457, 456, 298, 500, 233, 1027, 469, 1096, 426, 918, 160, 1067, 141, 1220, 189, 1245, 164, 1375, 297, 1378, 503, 1299, 702, 1550, 929, 1799, 855, 1752, 547, 1830, 602, 1928, 832, 1736, 796, 1735, 933, 1961, 1385, 1935, 1562, 2105, 1485, 2716, 1449, 2948, 1305, 2768, 1205, 2716, 1346, 2531, 1450, 2470, 1653, 3117, 2111, 3370, 2176, 2696, 1947, 2925, 2305, 3846, 2658, 2425, 2184, -877, 1981, -2261, 2623, -1645, 2908, -1876, 2732, -2704, 2953, -2484, 3116, -2120, 2954, -2442, 3216, -2466, 3499, -2192, 3234, -2392, 3361, -2497, 3869, -2078, 3772, -1858, 3915, -2066, 4438, -2285, 2934, -2294, -280, -2066, -1762, -1992, -1412, -2298, -1535, -2399, -1789, -2223, -1419, -2244, -1334, -2092, -1476, -1777, -1396, -2014, -1571, -2199, -1574, -1843, -1167, -1910, -1446, -2007, -1818];
 
 fn main() {
+    #[cfg(increase_thread_usage)]
+    let thread = std::thread::spawn(|| 4);
+
     for _ in 0..2 {
         mse(PCM.len(), PCM, EXPECTED);
     }

src/bin/miri.rs

@@ -195,6 +195,9 @@ fn main() {
                 "-Zmiri-disable-stacked-borrows" => {
                     miri_config.stacked_borrows = false;
                 }
+                "-Zmiri-disable-data-race-detector" => {
+                    miri_config.data_race_detector = false;
+                }
                 "-Zmiri-disable-alignment-check" => {
                     miri_config.check_alignment = miri::AlignmentCheck::None;
                 }