Merge from rustc

4 files changed, 63 insertions, 3 deletions

diff --git a/src/tools/miri/tests/fail/alloc/global_system_mixup.rs b/src/tools/miri/tests/fail/alloc/global_system_mixup.rs
index 804aa13660b..bbf069b7a2d 100644
--- a/src/tools/miri/tests/fail/alloc/global_system_mixup.rs
+++ b/src/tools/miri/tests/fail/alloc/global_system_mixup.rs
@@ -4,7 +4,9 @@
 
 //@normalize-stderr-test: "using [A-Za-z]+ heap deallocation operation" -> "using PLATFORM heap deallocation operation"
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
-//@normalize-stderr-test: "libc::free\([^()]*\)|unsafe \{ HeapFree\([^}]*\};" -> "FREE();"
+//@normalize-stderr-test: "unsafe \{ libc::free\([^()]*\) \}|unsafe \{ HeapFree\([^}]*\};" -> "FREE();"
+//@normalize-stderr-test: "alloc::[A-Za-z]+::" -> "alloc::PLATFORM::"
+//@normalize-stderr-test: "alloc/[A-Za-z]+.rs" -> "alloc/PLATFORM.rs"
 
 #![feature(allocator_api, slice_ptr_get)]
 
diff --git a/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr b/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
index 77909564149..287a1f1a3e3 100644
--- a/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
+++ b/src/tools/miri/tests/fail/alloc/global_system_mixup.stderr
@@ -1,5 +1,5 @@
 error: Undefined Behavior: deallocating ALLOC, which is Rust heap memory, using PLATFORM heap deallocation operation
-  --> RUSTLIB/std/src/sys/pal/PLATFORM/alloc.rs:LL:CC
+  --> RUSTLIB/std/src/sys/alloc/PLATFORM.rs:LL:CC
    |
 LL |         FREE();
    | ^ deallocating ALLOC, which is Rust heap memory, using PLATFORM heap deallocation operation
@@ -7,7 +7,7 @@ LL |         FREE();
    = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
-   = note: inside `std::sys::pal::PLATFORM::alloc::<impl std::alloc::GlobalAlloc for std::alloc::System>::dealloc` at RUSTLIB/std/src/sys/pal/PLATFORM/alloc.rs:LL:CC
+   = note: inside `std::sys::alloc::PLATFORM::<impl std::alloc::GlobalAlloc for std::alloc::System>::dealloc` at RUSTLIB/std/src/sys/alloc/PLATFORM.rs:LL:CC
    = note: inside `<std::alloc::System as std::alloc::Allocator>::deallocate` at RUSTLIB/std/src/alloc.rs:LL:CC
 note: inside `main`
   --> $DIR/global_system_mixup.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/weak_memory/weak_uninit.rs b/src/tools/miri/tests/fail/weak_memory/weak_uninit.rs
new file mode 100644
index 00000000000..54bea6c6908
--- /dev/null
+++ b/src/tools/miri/tests/fail/weak_memory/weak_uninit.rs
@@ -0,0 +1,43 @@
+//@compile-flags: -Zmiri-ignore-leaks -Zmiri-preemption-rate=0
+
+// Tests showing weak memory behaviours are exhibited. All tests
+// return true when the desired behaviour is seen.
+// This is scheduler and pseudo-RNG dependent, so each test is
+// run multiple times until one try returns true.
+// Spurious failure is possible, if you are really unlucky with
+// the RNG and always read the latest value from the store buffer.
+#![feature(new_uninit)]
+
+use std::sync::atomic::*;
+use std::thread::spawn;
+
+#[allow(dead_code)]
+#[derive(Copy, Clone)]
+struct EvilSend<T>(pub T);
+
+unsafe impl<T> Send for EvilSend<T> {}
+unsafe impl<T> Sync for EvilSend<T> {}
+
+// We can't create static items because we need to run each test multiple times.
+fn static_uninit_atomic() -> &'static AtomicUsize {
+    unsafe { Box::leak(Box::new_uninit()).assume_init_ref() }
+}
+
+fn relaxed() {
+    let x = static_uninit_atomic();
+    let j1 = spawn(move || {
+        x.store(1, Ordering::Relaxed);
+    });
+
+    let j2 = spawn(move || x.load(Ordering::Relaxed)); //~ERROR: using uninitialized data
+
+    j1.join().unwrap();
+    j2.join().unwrap();
+}
+
+pub fn main() {
+    // If we try often enough, we should hit UB.
+    for _ in 0..100 {
+        relaxed();
+    }
+}
diff --git a/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr b/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr
new file mode 100644
index 00000000000..9aa5bc2fa76
--- /dev/null
+++ b/src/tools/miri/tests/fail/weak_memory/weak_uninit.stderr
@@ -0,0 +1,15 @@
+error: Undefined Behavior: using uninitialized data, but this operation requires initialized memory
+  --> $DIR/weak_uninit.rs:LL:CC
+   |
+LL |     let j2 = spawn(move || x.load(Ordering::Relaxed));
+   |                            ^^^^^^^^^^^^^^^^^^^^^^^^^ using uninitialized data, but this operation requires initialized memory
+   |
+   = help: this indicates a bug in the program: it performed an invalid operation, and caused Undefined Behavior
+   = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
+   = note: BACKTRACE on thread `unnamed-ID`:
+   = note: inside closure at $DIR/weak_uninit.rs:LL:CC
+
+note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+
+error: aborting due to 1 previous error
+