A MIR transform that checks pointers are aligned

17 files changed, 54 insertions, 12 deletions

diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index 9f6adf3e3fa..cd9cc8bccb6 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -169,7 +169,7 @@ fn check_rvalue<'tcx>(
                 Err((span, "unsizing casts are not allowed in const fn".into()))
             }
         },
-        Rvalue::Cast(CastKind::PointerExposeAddress, _, _) => {
+        Rvalue::Cast(CastKind::PointerExposeAddress | CastKind::PointerAddress, _, _) => {
             Err((span, "casting pointers to ints is unstable in const fn".into()))
         },
         Rvalue::Cast(CastKind::DynStar, _, _) => {
diff --git a/src/tools/miri/src/shims/panic.rs b/src/tools/miri/src/shims/panic.rs
index 0ea1137200b..acc97c4b8a0 100644
--- a/src/tools/miri/src/shims/panic.rs
+++ b/src/tools/miri/src/shims/panic.rs
@@ -220,6 +220,34 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
                     },
                 )?;
             }
+            MisalignedPointerDereference { required, found } => {
+                // Forward to `panic_misaligned_pointer_dereference` lang item.
+
+                // First arg: required.
+                let required = this.read_scalar(&this.eval_operand(required, None)?)?;
+                // Second arg: found.
+                let found = this.read_scalar(&this.eval_operand(found, None)?)?;
+
+                // Call the lang item.
+                let panic_misaligned_pointer_dereference =
+                    this.tcx.lang_items().panic_misaligned_pointer_dereference_fn().unwrap();
+                let panic_misaligned_pointer_dereference =
+                    ty::Instance::mono(this.tcx.tcx, panic_misaligned_pointer_dereference);
+                this.call_function(
+                    panic_misaligned_pointer_dereference,
+                    Abi::Rust,
+                    &[required.into(), found.into()],
+                    None,
+                    StackPopCleanup::Goto {
+                        ret: None,
+                        unwind: match unwind {
+                            Some(cleanup) => StackPopUnwind::Cleanup(cleanup),
+                            None => StackPopUnwind::Skip,
+                        },
+                    },
+                )?;
+            }
+
             _ => {
                 // Forward everything else to `panic` lang item.
                 this.start_panic(
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/alignment.rs b/src/tools/miri/tests/fail/unaligned_pointers/alignment.rs
index 438e74e5b8d..6bb95ae4bcb 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/alignment.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/alignment.rs
@@ -1,4 +1,5 @@
 //@normalize-stderr-test: "\| +\^+" -> "| ^"
+//@compile-flags: -Cdebug-assertions=no
 
 fn main() {
     // No retry needed, this fails reliably.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.rs b/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.rs
index 9dd652fd821..29976836b0b 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/atomic_unaligned.rs
@@ -1,4 +1,4 @@
-//@compile-flags: -Zmiri-symbolic-alignment-check
+//@compile-flags: -Zmiri-symbolic-alignment-check -Cdebug-assertions=no
 #![feature(core_intrinsics)]
 
 fn main() {
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.rs b/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.rs
index cf3a558bb99..8a40e527f0e 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/drop_in_place.rs
@@ -1,3 +1,5 @@
+//@compile-flags: -Cdebug-assertions=no
+
 #[repr(transparent)]
 struct HasDrop(u8);
 
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
index ca8590cc6b3..6d31ded75c6 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/dyn_alignment.rs
@@ -1,5 +1,5 @@
 // should find the bug even without validation and stacked borrows, but gets masked by optimizations
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Zmir-opt-level=0
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Zmir-opt-level=0 -Cdebug-assertions=no
 
 #[repr(align(256))]
 #[derive(Debug)]
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.rs b/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.rs
index da4cadc1c87..c1041ee32a4 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/intptrcast_alignment_check.rs
@@ -1,4 +1,4 @@
-//@compile-flags: -Zmiri-symbolic-alignment-check -Zmiri-permissive-provenance
+//@compile-flags: -Zmiri-symbolic-alignment-check -Zmiri-permissive-provenance -Cdebug-assertions=no
 // With the symbolic alignment check, even with intptrcast and without
 // validation, we want to be *sure* to catch bugs that arise from pointers being
 // insufficiently aligned. The only way to achieve that is not not let programs
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
index 4a43db0aac5..4a8cf405ae2 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/reference_to_packed.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation/SB
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 
 #![allow(dead_code, unused_variables)]
 
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.rs
index 47d1f782cb6..921bcd6ce24 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr1.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation or Stacked Borrows.
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 
 fn main() {
     // Try many times as this might work by chance.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.rs
index c252944ffb7..8f597659f73 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr2.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation or Stacked Borrows.
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 
 fn main() {
     // No retry needed, this fails reliably.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
index 3aa8cb492a1..a7fcf30c6ea 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr3.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation or Stacked Borrows.
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 
 fn main() {
     // Try many times as this might work by chance.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
index 606316120d6..b8b01e113c9 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr4.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation or Stacked Borrows.
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 
 fn main() {
     // Make sure we notice when a u16 is loaded at offset 1 into a u8 allocation.
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_addr_of.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_addr_of.rs
index f1032ab52bc..b414b905472 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_addr_of.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_addr_of.rs
@@ -1,5 +1,5 @@
 // This should fail even without validation or Stacked Borrows.
-//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows
+//@compile-flags: -Zmiri-disable-validation -Zmiri-disable-stacked-borrows -Cdebug-assertions=no
 use std::ptr;
 
 fn main() {
diff --git a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
index eff42375956..04dbe3fd8d4 100644
--- a/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
+++ b/src/tools/miri/tests/fail/unaligned_pointers/unaligned_ptr_zst.rs
@@ -1,6 +1,6 @@
 // This should fail even without validation
 // Some optimizations remove ZST accesses, thus masking this UB.
-//@compile-flags: -Zmir-opt-level=0 -Zmiri-disable-validation
+//@compile-flags: -Zmir-opt-level=0 -Zmiri-disable-validation -Cdebug-assertions=no
 
 fn main() {
     // Try many times as this might work by chance.
diff --git a/src/tools/miri/tests/panic/alignment-assertion.rs b/src/tools/miri/tests/panic/alignment-assertion.rs
new file mode 100644
index 00000000000..68aa19a88db
--- /dev/null
+++ b/src/tools/miri/tests/panic/alignment-assertion.rs
@@ -0,0 +1,9 @@
+//@compile-flags: -Zmiri-disable-alignment-check -Cdebug-assertions=yes
+
+fn main() {
+    let mut x = [0u32; 2];
+    let ptr: *mut u8 = x.as_mut_ptr().cast::<u8>();
+    unsafe {
+        *(ptr.add(1).cast::<u32>()) = 42;
+    }
+}
diff --git a/src/tools/miri/tests/panic/alignment-assertion.stderr b/src/tools/miri/tests/panic/alignment-assertion.stderr
new file mode 100644
index 00000000000..26cf51b0cd2
--- /dev/null
+++ b/src/tools/miri/tests/panic/alignment-assertion.stderr
@@ -0,0 +1,2 @@
+thread 'main' panicked at 'misaligned pointer dereference: address must be a multiple of 0x4 but is $HEX', $DIR/alignment-assertion.rs:LL:CC
+note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
diff --git a/src/tools/miri/tests/pass/disable-alignment-check.rs b/src/tools/miri/tests/pass/disable-alignment-check.rs
index fdcacc6cea4..e8c0e027673 100644
--- a/src/tools/miri/tests/pass/disable-alignment-check.rs
+++ b/src/tools/miri/tests/pass/disable-alignment-check.rs
@@ -1,6 +1,6 @@
 //@revisions: stack tree
 //@[tree]compile-flags: -Zmiri-tree-borrows
-//@compile-flags: -Zmiri-disable-alignment-check
+//@compile-flags: -Zmiri-disable-alignment-check -Cdebug-assertions=no
 
 fn main() {
     let mut x = [0u8; 20];