adjust dangling-int-ptr error message

RalfJung · RalfJung · commit 46956f76ca6f · 2022-07-05T08:08:24.000-04:00
diff --git a/compiler/rustc_const_eval/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs
@@ -513,7 +513,7 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) {
         _ecx: &InterpCx<$mir, $tcx, Self>,
         addr: u64,
     ) -> Pointer<Option<AllocId>> {
-        Pointer::new(None, Size::from_bytes(addr))
+        Pointer::from_addr(addr)
     }
 
     #[inline(always)]
@@ -523,7 +523,7 @@ pub macro compile_time_machine(<$mir: lifetime, $tcx: lifetime>) {
     ) -> InterpResult<$tcx, Pointer<Option<AllocId>>> {
         // Allow these casts, but make the pointer not dereferenceable.
         // (I.e., they behave like transmutation.)
-        Ok(Pointer::new(None, Size::from_bytes(addr)))
+        Ok(Pointer::from_addr(addr))
     }
 
     #[inline(always)]
diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs
@@ -188,7 +188,7 @@ impl<'tcx, Tag: Provenance> MPlaceTy<'tcx, Tag> {
     #[inline]
     pub fn dangling(layout: TyAndLayout<'tcx>) -> Self {
         let align = layout.align.abi;
-        let ptr = Pointer::new(None, Size::from_bytes(align.bytes())); // no provenance, absolute address
+        let ptr = Pointer::from_addr(align.bytes()); // no provenance, absolute address
         // `Poison` this to make sure that the pointer value `ptr` is never observable by the program.
         MPlaceTy { mplace: MemPlace { ptr, meta: MemPlaceMeta::Poison }, layout, align }
     }
diff --git a/compiler/rustc_middle/src/mir/interpret/error.rs b/compiler/rustc_middle/src/mir/interpret/error.rs
@@ -186,17 +186,17 @@ pub enum CheckInAllocMsg {
 
 impl fmt::Display for CheckInAllocMsg {
     /// When this is printed as an error the context looks like this:
-    /// "{msg}0x01 is not a valid pointer".
+    /// "{msg}{pointer} is a dangling pointer".
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(
             f,
             "{}",
             match *self {
                 CheckInAllocMsg::DerefTest => "dereferencing pointer failed: ",
                 CheckInAllocMsg::MemoryAccessTest => "memory access failed: ",
-                CheckInAllocMsg::PointerArithmeticTest => "pointer arithmetic failed: ",
+                CheckInAllocMsg::PointerArithmeticTest => "out-of-bounds pointer arithmetic: ",
                 CheckInAllocMsg::OffsetFromTest => "out-of-bounds offset_from: ",
-                CheckInAllocMsg::InboundsTest => "",
+                CheckInAllocMsg::InboundsTest => "out-of-bounds pointer use: ",
             }
         )
     }
@@ -350,14 +350,12 @@ impl fmt::Display for UndefinedBehaviorInfo<'_> {
                 ptr_size = ptr_size.bytes(),
                 ptr_size_p = pluralize!(ptr_size.bytes()),
             ),
-            DanglingIntPointer(0, CheckInAllocMsg::InboundsTest) => {
-                write!(f, "null pointer is not a valid pointer for this operation")
-            }
-            DanglingIntPointer(0, msg) => {
-                write!(f, "{msg}null pointer is not a valid pointer")
-            }
             DanglingIntPointer(i, msg) => {
-                write!(f, "{msg}{i:#x} is not a valid pointer")
+                write!(
+                    f,
+                    "{msg}{pointer} is a dangling pointer (it has no provenance)",
+                    pointer = Pointer::<Option<AllocId>>::from_addr(*i),
+                )
             }
             AlignmentCheckFailed { required, has } => write!(
                 f,
diff --git a/compiler/rustc_middle/src/mir/interpret/pointer.rs b/compiler/rustc_middle/src/mir/interpret/pointer.rs
@@ -181,7 +181,17 @@ impl<Tag: Provenance> fmt::Debug for Pointer<Option<Tag>> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self.provenance {
             Some(tag) => Provenance::fmt(&Pointer::new(tag, self.offset), f),
-            None => write!(f, "{:#x}", self.offset.bytes()),
+            None => write!(f, "{:#x}[noalloc]", self.offset.bytes()),
+        }
+    }
+}
+
+impl<Tag: Provenance> fmt::Display for Pointer<Option<Tag>> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if self.provenance.is_none() && self.offset.bytes() == 0 {
+            write!(f, "null pointer")
+        } else {
+            fmt::Debug::fmt(self, f)
         }
     }
 }
@@ -226,9 +236,14 @@ impl<Tag> Pointer<Option<Tag>> {
 }
 
 impl<Tag> Pointer<Option<Tag>> {
+    #[inline(always)]
+    pub fn from_addr(addr: u64) -> Self {
+        Pointer { provenance: None, offset: Size::from_bytes(addr) }
+    }
+
     #[inline(always)]
     pub fn null() -> Self {
-        Pointer { provenance: None, offset: Size::ZERO }
+        Pointer::from_addr(0)
     }
 }
 
diff --git a/src/test/ui/const-ptr/forbidden_slices.32bit.stderr b/src/test/ui/const-ptr/forbidden_slices.32bit.stderr
@@ -4,7 +4,7 @@ error[E0080]: could not evaluate static initializer
 LL |         &*ptr::slice_from_raw_parts(data, len)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |         |
-   |         dereferencing pointer failed: null pointer is not a valid pointer
+   |         dereferencing pointer failed: null pointer is a dangling pointer (it has no provenance)
    |         inside `std::slice::from_raw_parts::<u32>` at $SRC_DIR/core/src/slice/raw.rs:LL:COL
    |
   ::: $DIR/forbidden_slices.rs:19:34
@@ -18,7 +18,7 @@ error[E0080]: could not evaluate static initializer
 LL |         &*ptr::slice_from_raw_parts(data, len)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |         |
-   |         dereferencing pointer failed: null pointer is not a valid pointer
+   |         dereferencing pointer failed: null pointer is a dangling pointer (it has no provenance)
    |         inside `std::slice::from_raw_parts::<()>` at $SRC_DIR/core/src/slice/raw.rs:LL:COL
    |
   ::: $DIR/forbidden_slices.rs:20:33
@@ -104,7 +104,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::ptr_offset_from_unsigned(self, origin) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  out-of-bounds offset_from: null pointer is not a valid pointer
+   |                  out-of-bounds offset_from: null pointer is a dangling pointer (it has no provenance)
    |                  inside `ptr::const_ptr::<impl *const u32>::sub_ptr` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $SRC_DIR/core/src/slice/raw.rs:LL:COL
@@ -144,7 +144,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: ALLOC_ID has size 4, so pointer to 8 bytes starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: ALLOC_ID has size 4, so pointer to 8 bytes starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u32>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
 ...
 LL |         unsafe { self.offset(count as isize) }
@@ -205,7 +205,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: ALLOC_ID has size 8, so pointer to 8 bytes starting at offset 1 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: ALLOC_ID has size 8, so pointer to 8 bytes starting at offset 1 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u64>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
 ...
 LL |         unsafe { self.offset(count as isize) }
diff --git a/src/test/ui/const-ptr/forbidden_slices.64bit.stderr b/src/test/ui/const-ptr/forbidden_slices.64bit.stderr
@@ -4,7 +4,7 @@ error[E0080]: could not evaluate static initializer
 LL |         &*ptr::slice_from_raw_parts(data, len)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |         |
-   |         dereferencing pointer failed: null pointer is not a valid pointer
+   |         dereferencing pointer failed: null pointer is a dangling pointer (it has no provenance)
    |         inside `std::slice::from_raw_parts::<u32>` at $SRC_DIR/core/src/slice/raw.rs:LL:COL
    |
   ::: $DIR/forbidden_slices.rs:19:34
@@ -18,7 +18,7 @@ error[E0080]: could not evaluate static initializer
 LL |         &*ptr::slice_from_raw_parts(data, len)
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |         |
-   |         dereferencing pointer failed: null pointer is not a valid pointer
+   |         dereferencing pointer failed: null pointer is a dangling pointer (it has no provenance)
    |         inside `std::slice::from_raw_parts::<()>` at $SRC_DIR/core/src/slice/raw.rs:LL:COL
    |
   ::: $DIR/forbidden_slices.rs:20:33
@@ -104,7 +104,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::ptr_offset_from_unsigned(self, origin) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  out-of-bounds offset_from: null pointer is not a valid pointer
+   |                  out-of-bounds offset_from: null pointer is a dangling pointer (it has no provenance)
    |                  inside `ptr::const_ptr::<impl *const u32>::sub_ptr` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $SRC_DIR/core/src/slice/raw.rs:LL:COL
@@ -144,7 +144,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: ALLOC_ID has size 4, so pointer to 8 bytes starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: ALLOC_ID has size 4, so pointer to 8 bytes starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u32>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
 ...
 LL |         unsafe { self.offset(count as isize) }
@@ -205,7 +205,7 @@ error[E0080]: could not evaluate static initializer
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: ALLOC_ID has size 8, so pointer to 8 bytes starting at offset 1 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: ALLOC_ID has size 8, so pointer to 8 bytes starting at offset 1 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u64>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
 ...
 LL |         unsafe { self.offset(count as isize) }
diff --git a/src/test/ui/consts/const-deref-ptr.stderr b/src/test/ui/consts/const-deref-ptr.stderr
@@ -2,7 +2,7 @@ error[E0080]: could not evaluate static initializer
   --> $DIR/const-deref-ptr.rs:4:29
    |
 LL |     static C: u64 = unsafe {*(0xdeadbeef as *const u64)};
-   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0xdeadbeef is not a valid pointer
+   |                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0xdeadbeef[noalloc] is a dangling pointer (it has no provenance)
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/consts/const-eval/const_raw_ptr_ops2.rs b/src/test/ui/consts/const-eval/const_raw_ptr_ops2.rs
@@ -5,6 +5,6 @@ const Z: i32 = unsafe { *(&1 as *const i32) };
 
 // bad, will thus error in miri
 const Z2: i32 = unsafe { *(42 as *const i32) }; //~ ERROR evaluation of constant value failed
-//~| is not a valid pointer
+//~| is a dangling pointer
 const Z3: i32 = unsafe { *(44 as *const i32) }; //~ ERROR evaluation of constant value failed
-//~| is not a valid pointer
+//~| is a dangling pointer
diff --git a/src/test/ui/consts/const-eval/const_raw_ptr_ops2.stderr b/src/test/ui/consts/const-eval/const_raw_ptr_ops2.stderr
@@ -2,13 +2,13 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/const_raw_ptr_ops2.rs:7:26
    |
 LL | const Z2: i32 = unsafe { *(42 as *const i32) };
-   |                          ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2a is not a valid pointer
+   |                          ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2a[noalloc] is a dangling pointer (it has no provenance)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/const_raw_ptr_ops2.rs:9:26
    |
 LL | const Z3: i32 = unsafe { *(44 as *const i32) };
-   |                          ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2c is not a valid pointer
+   |                          ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2c[noalloc] is a dangling pointer (it has no provenance)
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/consts/const-eval/ub-wide-ptr.32bit.stderr b/src/test/ui/consts/const-eval/ub-wide-ptr.32bit.stderr
@@ -319,7 +319,7 @@ error[E0080]: could not evaluate static initializer
   --> $DIR/ub-wide-ptr.rs:147:5
    |
 LL |     mem::transmute::<_, &dyn Trait>((&92u8, 0usize))
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is not a valid pointer
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is a dangling pointer (it has no provenance)
 
 error[E0080]: could not evaluate static initializer
   --> $DIR/ub-wide-ptr.rs:151:5
diff --git a/src/test/ui/consts/const-eval/ub-wide-ptr.64bit.stderr b/src/test/ui/consts/const-eval/ub-wide-ptr.64bit.stderr
@@ -319,7 +319,7 @@ error[E0080]: could not evaluate static initializer
   --> $DIR/ub-wide-ptr.rs:147:5
    |
 LL |     mem::transmute::<_, &dyn Trait>((&92u8, 0usize))
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is not a valid pointer
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is a dangling pointer (it has no provenance)
 
 error[E0080]: could not evaluate static initializer
   --> $DIR/ub-wide-ptr.rs:151:5
diff --git a/src/test/ui/consts/const-mut-refs/mut_ref_in_final_dynamic_check.rs b/src/test/ui/consts/const-mut-refs/mut_ref_in_final_dynamic_check.rs
@@ -11,7 +11,7 @@ const fn helper() -> Option<&'static mut i32> { unsafe {
     // Undefined behaviour (integer as pointer), who doesn't love tests like this.
     // This code never gets executed, because the static checks fail before that.
     Some(&mut *(42 as *mut i32)) //~ ERROR evaluation of constant value failed
-    //~| 0x2a is not a valid pointer
+    //~| 0x2a[noalloc] is a dangling pointer
 } }
 // The error is an evaluation error and not a validation error, so the error is reported
 // directly at the site where it occurs.
diff --git a/src/test/ui/consts/const-mut-refs/mut_ref_in_final_dynamic_check.stderr b/src/test/ui/consts/const-mut-refs/mut_ref_in_final_dynamic_check.stderr
@@ -4,7 +4,7 @@ error[E0080]: evaluation of constant value failed
 LL |     Some(&mut *(42 as *mut i32))
    |          ^^^^^^^^^^^^^^^^^^^^^^
    |          |
-   |          dereferencing pointer failed: 0x2a is not a valid pointer
+   |          dereferencing pointer failed: 0x2a[noalloc] is a dangling pointer (it has no provenance)
    |          inside `helper` at $DIR/mut_ref_in_final_dynamic_check.rs:13:10
 ...
 LL | const A: Option<&mut i32> = helper();
diff --git a/src/test/ui/consts/offset_from_ub.rs b/src/test/ui/consts/offset_from_ub.rs
@@ -34,14 +34,14 @@ pub const NOT_MULTIPLE_OF_SIZE: isize = {
 pub const OFFSET_FROM_NULL: isize = {
     let ptr = 0 as *const u8;
     unsafe { ptr_offset_from(ptr, ptr) } //~ERROR evaluation of constant value failed
-    //~| null pointer is not a valid pointer
+    //~| null pointer is a dangling pointer
 };
 
 pub const DIFFERENT_INT: isize = { // offset_from with two different integers: like DIFFERENT_ALLOC
     let ptr1 = 8 as *const u8;
     let ptr2 = 16 as *const u8;
     unsafe { ptr_offset_from(ptr2, ptr1) } //~ERROR evaluation of constant value failed
-    //~| 0x8 is not a valid pointer
+    //~| 0x8[noalloc] is a dangling pointer
 };
 
 const OUT_OF_BOUNDS_1: isize = {
diff --git a/src/test/ui/consts/offset_from_ub.stderr b/src/test/ui/consts/offset_from_ub.stderr
@@ -28,13 +28,13 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/offset_from_ub.rs:36:14
    |
 LL |     unsafe { ptr_offset_from(ptr, ptr) }
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ out-of-bounds offset_from: null pointer is not a valid pointer
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^ out-of-bounds offset_from: null pointer is a dangling pointer (it has no provenance)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/offset_from_ub.rs:43:14
    |
 LL |     unsafe { ptr_offset_from(ptr2, ptr1) }
-   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^ out-of-bounds offset_from: 0x8 is not a valid pointer
+   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^ out-of-bounds offset_from: 0x8[noalloc] is a dangling pointer (it has no provenance)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/offset_from_ub.rs:52:14
diff --git a/src/test/ui/consts/offset_ub.stderr b/src/test/ui/consts/offset_ub.stderr
@@ -18,7 +18,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: allocN has size 1, so pointer to 2 bytes starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: allocN has size 1, so pointer to 2 bytes starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:8:43
@@ -32,7 +32,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: allocN has size 100, so pointer to 101 bytes starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: allocN has size 100, so pointer to 101 bytes starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:9:45
@@ -102,7 +102,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: allocN has size 1, so pointer to 2 bytes starting at offset -4 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: allocN has size 1, so pointer to 2 bytes starting at offset -4 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:15:49
@@ -116,7 +116,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: allocN has size 0, so pointer to 1 byte starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: allocN has size 0, so pointer to 1 byte starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:17:50
@@ -130,7 +130,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) as *mut T }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: 0x1 is not a valid pointer
+   |                  out-of-bounds pointer arithmetic: 0x1[noalloc] is a dangling pointer (it has no provenance)
    |                  inside `ptr::mut_ptr::<impl *mut u8>::offset` at $SRC_DIR/core/src/ptr/mut_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:18:42
@@ -144,7 +144,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: null pointer is not a valid pointer
+   |                  out-of-bounds pointer arithmetic: null pointer is a dangling pointer (it has no provenance)
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:21:50
@@ -158,7 +158,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: 0x7f..f is not a valid pointer
+   |                  out-of-bounds pointer arithmetic: 0x7f..f[noalloc] is a dangling pointer (it has no provenance)
    |                  inside `ptr::const_ptr::<impl *const u8>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/offset_ub.rs:24:47
diff --git a/src/test/ui/consts/ptr_comparisons.stderr b/src/test/ui/consts/ptr_comparisons.stderr
@@ -4,7 +4,7 @@ error[E0080]: evaluation of constant value failed
 LL |         unsafe { intrinsics::offset(self, count) }
    |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |                  |
-   |                  pointer arithmetic failed: alloc3 has size $WORD, so pointer to $TWO_WORDS bytes starting at offset 0 is out-of-bounds
+   |                  out-of-bounds pointer arithmetic: alloc3 has size $WORD, so pointer to $TWO_WORDS bytes starting at offset 0 is out-of-bounds
    |                  inside `ptr::const_ptr::<impl *const usize>::offset` at $SRC_DIR/core/src/ptr/const_ptr.rs:LL:COL
    |
   ::: $DIR/ptr_comparisons.rs:58:34
diff --git a/src/test/ui/error-codes/E0396-fixed.stderr b/src/test/ui/error-codes/E0396-fixed.stderr

Original file line number	Diff line number	Diff line change
`@@ -188,7 +188,7 @@ impl<'tcx, Tag: Provenance> MPlaceTy<'tcx, Tag> {`
`188`	`188`	`#[inline]`
`189`	`189`	`pub fn dangling(layout: TyAndLayout<'tcx>) -> Self {`
`190`	`190`	`let align = layout.align.abi;`
`191`		`- let ptr = Pointer::new(None, Size::from_bytes(align.bytes())); // no provenance, absolute address`
	`191`	`+ let ptr = Pointer::from_addr(align.bytes()); // no provenance, absolute address`
`192`	`192`	// `Poison` this to make sure that the pointer value `ptr` is never observable by the program.
`193`	`193`	`MPlaceTy { mplace: MemPlace { ptr, meta: MemPlaceMeta::Poison }, layout, align }`
`194`	`194`	`}`
Original file line number	Diff line number	Diff line change
`@@ -181,7 +181,17 @@ impl<Tag: Provenance> fmt::Debug for Pointer<Option<Tag>> {`
`181`	`181`	`fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {`
`182`	`182`	`match self.provenance {`
`183`	`183`	`Some(tag) => Provenance::fmt(&Pointer::new(tag, self.offset), f),`
`184`		`- None => write!(f, "{:#x}", self.offset.bytes()),`
	`184`	`+ None => write!(f, "{:#x}[noalloc]", self.offset.bytes()),`
	`185`	`+ }`
	`186`	`+ }`
	`187`	`+}`
	`188`	`+`
	`189`	`+impl<Tag: Provenance> fmt::Display for Pointer<Option<Tag>> {`
	`190`	`+ fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {`
	`191`	`+ if self.provenance.is_none() && self.offset.bytes() == 0 {`
	`192`	`+ write!(f, "null pointer")`
	`193`	`+ } else {`
	`194`	`+ fmt::Debug::fmt(self, f)`
`185`	`195`	`}`
`186`	`196`	`}`
`187`	`197`	`}`
`@@ -226,9 +236,14 @@ impl<Tag> Pointer<Option<Tag>> {`
`226`	`236`	`}`
`227`	`237`
`228`	`238`	`impl<Tag> Pointer<Option<Tag>> {`
	`239`	`+ #[inline(always)]`
	`240`	`+ pub fn from_addr(addr: u64) -> Self {`
	`241`	`+ Pointer { provenance: None, offset: Size::from_bytes(addr) }`
	`242`	`+ }`
	`243`	`+`
`229`	`244`	`#[inline(always)]`
`230`	`245`	`pub fn null() -> Self {`
`231`		`- Pointer { provenance: None, offset: Size::ZERO }`
	`246`	`+ Pointer::from_addr(0)`
`232`	`247`	`}`
`233`	`248`	`}`
`234`	`249`
Original file line number	Diff line number	Diff line change
`@@ -2,7 +2,7 @@ error[E0080]: could not evaluate static initializer`
`2`	`2`	`--> $DIR/const-deref-ptr.rs:4:29`
`3`	`3`	`\|`
`4`	`4`	`LL \| static C: u64 = unsafe {(0xdeadbeef as const u64)};`
`5`		`- \| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0xdeadbeef is not a valid pointer`
	`5`	`+ \| ^^^^^^^^^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0xdeadbeef[noalloc] is a dangling pointer (it has no provenance)`
`6`	`6`
`7`	`7`	`error: aborting due to previous error`
`8`	`8`
Original file line number	Diff line number	Diff line change
`@@ -2,13 +2,13 @@ error[E0080]: evaluation of constant value failed`
`2`	`2`	`--> $DIR/const_raw_ptr_ops2.rs:7:26`
`3`	`3`	`\|`
`4`	`4`	`LL \| const Z2: i32 = unsafe { (42 as const i32) };`
`5`		`- \| ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2a is not a valid pointer`
	`5`	`+ \| ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2a[noalloc] is a dangling pointer (it has no provenance)`
`6`	`6`
`7`	`7`	`error[E0080]: evaluation of constant value failed`
`8`	`8`	`--> $DIR/const_raw_ptr_ops2.rs:9:26`
`9`	`9`	`\|`
`10`	`10`	`LL \| const Z3: i32 = unsafe { (44 as const i32) };`
`11`		`- \| ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2c is not a valid pointer`
	`11`	`+ \| ^^^^^^^^^^^^^^^^^^^ dereferencing pointer failed: 0x2c[noalloc] is a dangling pointer (it has no provenance)`
`12`	`12`
`13`	`13`	`error: aborting due to 2 previous errors`
`14`	`14`
Original file line number	Diff line number	Diff line change
`@@ -319,7 +319,7 @@ error[E0080]: could not evaluate static initializer`
`319`	`319`	`--> $DIR/ub-wide-ptr.rs:147:5`
`320`	`320`	`\|`
`321`	`321`	`LL \| mem::transmute::<_, &dyn Trait>((&92u8, 0usize))`
`322`		`- \| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is not a valid pointer`
	`322`	`+ \| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ memory access failed: null pointer is a dangling pointer (it has no provenance)`
`323`	`323`
`324`	`324`	`error[E0080]: could not evaluate static initializer`
`325`	`325`	`--> $DIR/ub-wide-ptr.rs:151:5`