Miri: add a flag to do recursive validity checking

2 files changed, 23 insertions, 0 deletions

diff --git a/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.rs b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.rs
new file mode 100644
index 00000000000..17b81f29cfe
--- /dev/null
+++ b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.rs
@@ -0,0 +1,8 @@
+//@compile-flags: -Zmiri-recursive-validation
+
+fn main() {
+    let x = 3u8;
+    let xref = &x;
+    let xref_wrong_type: &bool = unsafe { std::mem::transmute(xref) }; //~ERROR: encountered 0x03, but expected a boolean
+    let _val = *xref_wrong_type;
+}
diff --git a/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr
new file mode 100644
index 00000000000..2b2fa9b8a20
--- /dev/null
+++ b/src/tools/miri/tests/fail/validity/recursive-validity-ref-bool.stderr
@@ -0,0 +1,15 @@
+error: Undefined Behavior: constructing invalid value at .<deref>: encountered 0x03, but expected a boolean
+  --> $DIR/recursive-validity-ref-bool.rs:LL:CC
+   |
+LL |     let xref_wrong_type: &bool = unsafe { std::mem::transmute(xref) };
+   |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^ constructing invalid value at .<deref>: encountered 0x03, but expected a boolean
+   |
+   = 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/recursive-validity-ref-bool.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
+