Auto merge of #2195 - RalfJung:vtable-validation, r=RalfJung

test for Stacked Borrows error during vtable validation

Fixes https://github.com/rust-lang/miri/issues/2123
Needs https://github.com/rust-lang/rust/pull/97761

rust-version

@@ -1 +1 @@
-09d52bc5d4260bac8b9a2ea8ac7a07c5c72906f1
+99930ac7f8cbb5d9b319b2e2e92794fd6f24f556

src/diagnostics.rs

@@ -16,10 +16,9 @@ pub enum TerminationInfo {
     Exit(i64),
     Abort(String),
     UnsupportedInIsolation(String),
-    ExperimentalUb {
+    StackedBorrowsUb {
         msg: String,
         help: Option<String>,
-        url: String,
         history: Option<TagHistory>,
     },
     Deadlock,
@@ -43,7 +42,7 @@ impl fmt::Display for TerminationInfo {
             Exit(code) => write!(f, "the evaluated program completed with exit code {}", code),
             Abort(msg) => write!(f, "{}", msg),
             UnsupportedInIsolation(msg) => write!(f, "{}", msg),
-            ExperimentalUb { msg, .. } => write!(f, "{}", msg),
+            StackedBorrowsUb { msg, .. } => write!(f, "{}", msg),
             Deadlock => write!(f, "the evaluated program deadlocked"),
             MultipleSymbolDefinitions { link_name, .. } =>
                 write!(f, "multiple definitions of symbol `{}`", link_name),
@@ -146,7 +145,7 @@ pub fn report_error<'tcx, 'mir>(
                 Exit(code) => return Some(*code),
                 Abort(_) => Some("abnormal termination"),
                 UnsupportedInIsolation(_) => Some("unsupported operation"),
-                ExperimentalUb { .. } => Some("Undefined Behavior"),
+                StackedBorrowsUb { .. } => Some("Undefined Behavior"),
                 Deadlock => Some("deadlock"),
                 MultipleSymbolDefinitions { .. } | SymbolShimClashing { .. } => None,
             };
@@ -157,11 +156,12 @@ pub fn report_error<'tcx, 'mir>(
                         (None, format!("pass the flag `-Zmiri-disable-isolation` to disable isolation;")),
                         (None, format!("or pass `-Zmiri-isolation-error=warn` to configure Miri to return an error code from isolated operations (if supported for that operation) and continue with a warning")),
                     ],
-                ExperimentalUb { url, help, history, .. } => {
+                StackedBorrowsUb { help, history, .. } => {
+                    let url = "https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md";
                     msg.extend(help.clone());
                     let mut helps = vec![
-                        (None, format!("this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental")),
-                        (None, format!("see {} for further information", url)),
+                        (None, format!("this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental")),
+                        (None, format!("see {url} for further information")),
                     ];
                     match history {
                         Some(TagHistory::Tagged {tag, created: (created_range, created_span), invalidated, protected }) => {

src/stacked_borrows.rs

@@ -250,14 +250,7 @@ pub fn err_sb_ub<'tcx>(
     help: Option<String>,
     history: Option<TagHistory>,
 ) -> InterpError<'tcx> {
-    err_machine_stop!(TerminationInfo::ExperimentalUb {
-        msg,
-        help,
-        url: format!(
-            "https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md"
-        ),
-        history
-    })
+    err_machine_stop!(TerminationInfo::StackedBorrowsUb { msg, help, history })
 }
 
 // # Stacked Borrows Core Begin

tests/fail/box-cell-alias.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { (*ptr).set(20); }
    |              trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of a reborrow at ALLOC[0x0..0x1]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x1]
   --> $DIR/box-cell-alias.rs:LL:CC

tests/fail/stacked_borrows/alias_through_mutation.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *target_alias;
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/alias_through_mutation.rs:LL:CC

tests/fail/stacked_borrows/aliasing_mut1.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because incompatible
 LL | pub fn safe(_x: &mut i32, _y: &mut i32) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because incompatible item is protected: [Unique for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/aliasing_mut1.rs:LL:CC

tests/fail/stacked_borrows/aliasing_mut2.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because incompatible
 LL | pub fn safe(_x: &i32, _y: &mut i32) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because incompatible item is protected: [SharedReadOnly for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/aliasing_mut2.rs:LL:CC

tests/fail/stacked_borrows/aliasing_mut3.stderr

@@ -7,7 +7,7 @@ LL | pub fn safe(_x: &mut i32, _y: &i32) {}
    | trying to reborrow <untagged> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    | this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/aliasing_mut3.rs:LL:CC

tests/fail/stacked_borrows/aliasing_mut4.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <TAG> because incompatible
 LL | pub fn safe(_x: &i32, _y: &mut Cell<i32>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ not granting access to tag <TAG> because incompatible item is protected: [SharedReadOnly for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/aliasing_mut4.rs:LL:CC

tests/fail/stacked_borrows/box_exclusive_violation1.stderr

@@ -7,7 +7,7 @@ LL |   *our
    |   attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |   this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/box_exclusive_violation1.rs:LL:CC

tests/fail/stacked_borrows/buggy_as_mut_slice.stderr

@@ -7,7 +7,7 @@ LL |     v1[1] = 5;
    |     attempting a write access using <TAG> at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of an access at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0xc]
   --> $DIR/buggy_as_mut_slice.rs:LL:CC

tests/fail/stacked_borrows/buggy_split_at_mut.stderr

@@ -7,7 +7,7 @@ LL |     let (a, b) = safe::split_at_mut(&mut array, 0);
    |          trying to reborrow <TAG> for Unique permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |          this error occurs as part of a reborrow at ALLOC[0x0..0x10]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x10]
   --> $DIR/buggy_split_at_mut.rs:LL:CC

tests/fail/stacked_borrows/deallocate_against_barrier1.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: deallocating while item is protected: [Unique for <TA
 LL |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating while item is protected: [Unique for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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 `std::alloc::dealloc` at RUSTLIB/alloc/src/alloc.rs:LL:CC

tests/fail/stacked_borrows/deallocate_against_barrier2.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: deallocating while item is protected: [SharedReadWrit
 LL |     unsafe { __rust_dealloc(ptr, layout.size(), layout.align()) }
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ deallocating while item is protected: [SharedReadWrite for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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 `std::alloc::dealloc` at RUSTLIB/alloc/src/alloc.rs:LL:CC

tests/fail/stacked_borrows/illegal_read1.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref; // ...but any use of raw will invalidate our ref.
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read1.rs:LL:CC

tests/fail/stacked_borrows/illegal_read2.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref; // ...but any use of raw will invalidate our ref.
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read2.rs:LL:CC

tests/fail/stacked_borrows/illegal_read3.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref2;
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read3.rs:LL:CC

tests/fail/stacked_borrows/illegal_read4.stderr

@@ -7,7 +7,7 @@ LL |     let _illegal = *xref2;
    |                    attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                    this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read4.rs:LL:CC

tests/fail/stacked_borrows/illegal_read5.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref; // the mutable one is dead and gone
    |                attempting a read access using <TAG> at ALLOC[$HEX], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[$HEX..$HEX]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
 help: <TAG> was created by a retag at offsets [$HEX..$HEX]
   --> $DIR/illegal_read5.rs:LL:CC

tests/fail/stacked_borrows/illegal_read6.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *raw;
    |                attempting a read access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/illegal_read6.rs:LL:CC

tests/fail/stacked_borrows/illegal_read7.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *x.get_mut();
    |                 trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                 this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read7.rs:LL:CC

tests/fail/stacked_borrows/illegal_read8.stderr

@@ -7,7 +7,7 @@ LL |     let _fail = *y1;
    |                 attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                 this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_read8.rs:LL:CC

tests/fail/stacked_borrows/illegal_write1.stderr

@@ -7,7 +7,7 @@ LL |     let _x = *xref;
    |              attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_write1.rs:LL:CC

tests/fail/stacked_borrows/illegal_write2.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *target2 = 13; }
    |              attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/illegal_write2.rs:LL:CC

tests/fail/stacked_borrows/illegal_write3.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *ptr = 42; }
    |              attempting a write access using <untagged> at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/illegal_write3.rs:LL:CC

tests/fail/stacked_borrows/illegal_write4.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *reference;
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_write4.rs:LL:CC

tests/fail/stacked_borrows/illegal_write5.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref;
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/illegal_write5.rs:LL:CC

tests/fail/stacked_borrows/illegal_write6.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <untagged> because incompa
 LL |     unsafe { *y = 2; }
    |              ^^^^^^ not granting access to tag <untagged> because incompatible item is protected: [Unique for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/illegal_write6.rs:LL:CC

tests/fail/stacked_borrows/interior_mut1.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *inner_shr.get();
    |                 trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                 this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/interior_mut1.rs:LL:CC

tests/fail/stacked_borrows/interior_mut2.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *inner_shr.get();
    |                 trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                 this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/interior_mut2.rs:LL:CC

tests/fail/stacked_borrows/invalidate_against_barrier1.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <untagged> because incompa
 LL |     let _val = unsafe { *x };
    |                         ^^ not granting access to tag <untagged> because incompatible item is protected: [Unique for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/invalidate_against_barrier1.rs:LL:CC

tests/fail/stacked_borrows/invalidate_against_barrier2.stderr

@@ -4,7 +4,7 @@ error: Undefined Behavior: not granting access to tag <untagged> because incompa
 LL |     unsafe { *x = 0 };
    |              ^^^^^^ not granting access to tag <untagged> because incompatible item is protected: [SharedReadOnly for <TAG> (call ID)]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/invalidate_against_barrier2.rs:LL:CC

tests/fail/stacked_borrows/load_invalid_mut.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref_in_mem;
    |                trying to reborrow <TAG> for Unique permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/load_invalid_mut.rs:LL:CC

tests/fail/stacked_borrows/load_invalid_shr.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *xref_in_mem;
    |                trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/load_invalid_shr.rs:LL:CC

tests/fail/stacked_borrows/mut_exclusive_violation1.stderr

@@ -7,7 +7,7 @@ LL |     *LEAK = 7;
    |     attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/mut_exclusive_violation1.rs:LL:CC

tests/fail/stacked_borrows/mut_exclusive_violation2.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *raw1;
    |                attempting a read access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/mut_exclusive_violation2.rs:LL:CC

tests/fail/stacked_borrows/outdated_local.stderr

@@ -7,7 +7,7 @@ LL |     assert_eq!(unsafe { *y }, 1);
    |                         attempting a read access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                         this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/outdated_local.rs:LL:CC

tests/fail/stacked_borrows/pass_invalid_mut.stderr

@@ -7,7 +7,7 @@ LL |     foo(xref);
    |         trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |         this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/pass_invalid_mut.rs:LL:CC

tests/fail/stacked_borrows/pass_invalid_shr.stderr

@@ -7,7 +7,7 @@ LL |     foo(xref);
    |         trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |         this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/pass_invalid_shr.rs:LL:CC

tests/fail/stacked_borrows/pointer_smuggling.stderr

@@ -7,7 +7,7 @@ LL |     let _x = unsafe { *PTR };
    |                       attempting a read access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |                       this error occurs as part of an access at ALLOC[0x0..0x1]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x1]
   --> $DIR/pointer_smuggling.rs:LL:CC

tests/fail/stacked_borrows/raw_tracking.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *raw1 = 13; }
    |              attempting a write access using <TAG> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/raw_tracking.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_mut.stderr

@@ -7,7 +7,7 @@ LL |     ret
    |     trying to reborrow <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_mut.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_mut_option.stderr

@@ -7,7 +7,7 @@ LL |         Some(_x) => {},
    |              trying to reborrow <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_mut_option.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_mut_tuple.stderr

@@ -7,7 +7,7 @@ LL |     foo(&mut (1, 2)).0;
    |     trying to reborrow <TAG> for Unique permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_mut_tuple.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_shr.stderr

@@ -7,7 +7,7 @@ LL |     ret
    |     trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_shr.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_shr_option.stderr

@@ -7,7 +7,7 @@ LL |         Some(_x) => {},
    |              trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_shr_option.rs:LL:CC

tests/fail/stacked_borrows/return_invalid_shr_tuple.stderr

@@ -7,7 +7,7 @@ LL |     foo(&mut (1, 2)).0;
    |     trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x4..0x8]
   --> $DIR/return_invalid_shr_tuple.rs:LL:CC

tests/fail/stacked_borrows/shared_rw_borrows_are_weak1.stderr

@@ -7,7 +7,7 @@ LL |     y.get_mut();
    |     trying to reborrow <TAG> for SharedReadWrite permission at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |     this error occurs as part of a reborrow at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x4]
   --> $DIR/shared_rw_borrows_are_weak1.rs:LL:CC

tests/fail/stacked_borrows/shared_rw_borrows_are_weak2.stderr

@@ -7,7 +7,7 @@ LL |     let _val = *y;
    |                attempting a read access using <TAG> at ALLOC[$HEX], but that tag does not exist in the borrow stack for this location
    |                this error occurs as part of an access at ALLOC[$HEX..$HEX]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows rules it violated are still experimental
    = help: see https://github.com/rust-lang/unsafe-code-guidelines/blob/master/wip/stacked-borrows.md for further information
 help: <TAG> was created by a retag at offsets [$HEX..$HEX]
   --> $DIR/shared_rw_borrows_are_weak2.rs:LL:CC

tests/fail/stacked_borrows/shr_frozen_violation1.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *(x as *const i32 as *mut i32) = 7; }
    |              attempting a write access using <untagged> at ALLOC[0x0], but that tag only grants SharedReadOnly permission for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/shr_frozen_violation1.rs:LL:CC

tests/fail/stacked_borrows/transmute-is-no-escape.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *raw = 13; }
    |              attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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 `main` at $DIR/transmute-is-no-escape.rs:LL:CC

tests/fail/stacked_borrows/unescaped_local.stderr

@@ -7,7 +7,7 @@ LL |     unsafe { *raw = 13; }
    |              attempting a write access using <untagged> at ALLOC[0x0], but that tag does not exist in the borrow stack for this location
    |              this error occurs as part of an access at ALLOC[0x0..0x4]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: tag was most recently created at offsets [0x0..0x4]
   --> $DIR/unescaped_local.rs:LL:CC

tests/fail/stacked_borrows/unescaped_static.stderr

@@ -7,7 +7,7 @@ LL |     let _val = unsafe { *ptr_to_first.add(1) };
    |                         attempting a read access using <untagged> at ALLOC[0x1], but that tag does not exist in the borrow stack for this location
    |                         this error occurs as part of an access at ALLOC[0x1..0x2]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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 `main` at $DIR/unescaped_static.rs:LL:CC

tests/fail/stacked_borrows/vtable.rs

@@ -0,0 +1,19 @@
+// error-pattern: vtable pointer does not have permission
+#![feature(ptr_metadata)]
+
+trait Foo {}
+
+impl Foo for u32 {}
+
+fn uwu(thin: *const (), meta: &'static ()) -> *const dyn Foo {
+    core::ptr::from_raw_parts(thin, unsafe { core::mem::transmute(meta) })
+}
+
+fn main() {
+    unsafe {
+        let orig = 1_u32;
+        let x = &orig as &dyn Foo;
+        let (ptr, meta) = (x as *const dyn Foo).to_raw_parts();
+        let _ = uwu(ptr, core::mem::transmute(meta));
+    }
+}

tests/fail/stacked_borrows/vtable.stderr

@@ -0,0 +1,25 @@
+error: Undefined Behavior: type validation failed: encountered vtable pointer does not have permission to read drop function pointer
+  --> RUSTLIB/core/src/ptr/metadata.rs:LL:CC
+   |
+LL |     unsafe { PtrRepr { components: PtrComponents { data_address, metadata } }.const_ptr }
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type validation failed: encountered vtable pointer does not have permission to read drop function pointer
+   |
+   = 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: inside `std::ptr::from_raw_parts::<dyn Foo>` at RUSTLIB/core/src/ptr/metadata.rs:LL:CC
+note: inside `uwu` at $DIR/vtable.rs:LL:CC
+  --> $DIR/vtable.rs:LL:CC
+   |
+LL |     core::ptr::from_raw_parts(thin, unsafe { core::mem::transmute(meta) })
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: inside `main` at $DIR/vtable.rs:LL:CC
+  --> $DIR/vtable.rs:LL:CC
+   |
+LL |         let _ = uwu(ptr, core::mem::transmute(meta));
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+note: some details are omitted, run with `MIRIFLAGS=-Zmiri-backtrace=full` for a verbose backtrace
+
+error: aborting due to previous error
+

tests/fail/stacked_borrows/zst_slice.stderr

@@ -7,7 +7,7 @@ LL |         unsafe { &*index.get_unchecked(self) }
    |                  trying to reborrow <TAG> for SharedReadOnly permission at ALLOC[0x4], but that tag does not exist in the borrow stack for this location
    |                  this error occurs as part of a reborrow at ALLOC[0x4..0x8]
    |
-   = help: this indicates a potential bug in the program: it performed an invalid operation, but the rules it violated are still experimental
+   = help: this indicates a potential bug in the program: it performed an invalid operation, but the Stacked Borrows 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
 help: <TAG> was created by a retag at offsets [0x0..0x0]
   --> $DIR/zst_slice.rs:LL:CC