detect when pthread_rwlock_t is moved

For some implementations of pthreads, the address of pthread_rwlock_t
(or its fields) is used to identify the lock. That means that if the
contents of a pthread_rwlock_t are moved in memory, effectively a new
lock object is created, which is completely independted from the
original. Thus we want to detect when when such objects are moved and
show an error.

2 files changed, 29 insertions, 0 deletions

diff --git a/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.rs b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.rs
new file mode 100644
index 00000000000..b51bae79849
--- /dev/null
+++ b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.rs
@@ -0,0 +1,14 @@
+//@ignore-target-windows: No pthreads on Windows
+
+fn main() {
+    unsafe {
+        let mut rw = libc::PTHREAD_RWLOCK_INITIALIZER;
+
+        libc::pthread_rwlock_rdlock(&mut rw as *mut _);
+
+        // Move rwlock
+        let mut rw2 = rw;
+
+        libc::pthread_rwlock_unlock(&mut rw2 as *mut _); //~ ERROR: pthread_rwlock_t can't be moved after first use
+    }
+}
diff --git a/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr
new file mode 100644
index 00000000000..8a5ec4aa98d
--- /dev/null
+++ b/src/tools/miri/tests/fail-dep/concurrency/libx_pthread_rwlock_moved.stderr
@@ -0,0 +1,15 @@
+error: Undefined Behavior: pthread_rwlock_t can't be moved after first use
+  --> $DIR/libx_pthread_rwlock_moved.rs:LL:CC
+   |
+LL |         libc::pthread_rwlock_unlock(&mut rw2 as *mut _);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ pthread_rwlock_t can't be moved after first use
+   |
+   = 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 `main` at $DIR/libx_pthread_rwlock_moved.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
+