Rollup merge of #102194 - fee1-dead-contrib:improve-const-drop, r=oli-obk

Note the type when unable to drop values in compile time

compiler/rustc_const_eval/src/transform/check_consts/check.rs

@@ -1009,7 +1009,10 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
 
                 if needs_non_const_drop {
                     self.check_op_spanned(
-                        ops::LiveDrop { dropped_at: Some(terminator.source_info.span) },
+                        ops::LiveDrop {
+                            dropped_at: Some(terminator.source_info.span),
+                            dropped_ty: ty_of_dropped_place,
+                        },
                         err_span,
                     );
                 }

compiler/rustc_const_eval/src/transform/check_consts/ops.rs

@@ -422,10 +422,11 @@ impl<'tcx> NonConstOp<'tcx> for InlineAsm {
 }
 
 #[derive(Debug)]
-pub struct LiveDrop {
+pub struct LiveDrop<'tcx> {
     pub dropped_at: Option<Span>,
+    pub dropped_ty: Ty<'tcx>,
 }
-impl<'tcx> NonConstOp<'tcx> for LiveDrop {
+impl<'tcx> NonConstOp<'tcx> for LiveDrop<'tcx> {
     fn build_error(
         &self,
         ccx: &ConstCx<'_, 'tcx>,
@@ -435,9 +436,13 @@ impl<'tcx> NonConstOp<'tcx> for LiveDrop {
             ccx.tcx.sess,
             span,
             E0493,
-            "destructors cannot be evaluated at compile-time"
+            "destructor of `{}` cannot be evaluated at compile-time",
+            self.dropped_ty,
+        );
+        err.span_label(
+            span,
+            format!("the destructor for this type cannot be evaluated in {}s", ccx.const_kind()),
         );
-        err.span_label(span, format!("{}s cannot evaluate destructors", ccx.const_kind()));
         if let Some(span) = self.dropped_at {
             err.span_label(span, "value is dropped here");
         }

compiler/rustc_const_eval/src/transform/check_consts/post_drop_elaboration.rs

@@ -1,6 +1,6 @@
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::{self, BasicBlock, Location};
-use rustc_middle::ty::TyCtxt;
+use rustc_middle::ty::{Ty, TyCtxt};
 use rustc_span::{symbol::sym, Span};
 
 use super::check::Qualifs;
@@ -58,9 +58,9 @@ impl<'mir, 'tcx> std::ops::Deref for CheckLiveDrops<'mir, 'tcx> {
     }
 }
 
-impl CheckLiveDrops<'_, '_> {
+impl<'tcx> CheckLiveDrops<'_, 'tcx> {
-    fn check_live_drop(&self, span: Span) {
+    fn check_live_drop(&self, span: Span, dropped_ty: Ty<'tcx>) {
-        ops::LiveDrop { dropped_at: None }.build_error(self.ccx, span).emit();
+        ops::LiveDrop { dropped_at: None, dropped_ty }.build_error(self.ccx, span).emit();
     }
 }
 
@@ -90,7 +90,7 @@ impl<'tcx> Visitor<'tcx> for CheckLiveDrops<'_, 'tcx> {
                 }
 
                 if dropped_place.is_indirect() {
-                    self.check_live_drop(terminator.source_info.span);
+                    self.check_live_drop(terminator.source_info.span, dropped_ty);
                     return;
                 }
 
@@ -101,7 +101,7 @@ impl<'tcx> Visitor<'tcx> for CheckLiveDrops<'_, 'tcx> {
                 if self.qualifs.needs_non_const_drop(self.ccx, dropped_place.local, location) {
                     // Use the span where the dropped local was declared for the error.
                     let span = self.body.local_decls[dropped_place.local].source_info.span;
-                    self.check_live_drop(span);
+                    self.check_live_drop(span, dropped_ty);
                 }
             }
 

src/test/ui/check-static-values-constraints.rs

@@ -63,7 +63,7 @@ static STATIC8: SafeStruct = SafeStruct{field1: SafeEnum::Variant1,
 // This example should fail because field1 in the base struct is not safe
 static STATIC9: SafeStruct = SafeStruct{field1: SafeEnum::Variant1,
                                         ..SafeStruct{field1: SafeEnum::Variant3(WithDtor),
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
                                                      field2: SafeEnum::Variant1}};
 
 struct UnsafeStruct;

src/test/ui/check-static-values-constraints.stderr

@@ -1,4 +1,4 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `SafeStruct` cannot be evaluated at compile-time
   --> $DIR/check-static-values-constraints.rs:65:43
    |
 LL |                                           ..SafeStruct{field1: SafeEnum::Variant3(WithDtor),
@@ -7,7 +7,7 @@ LL | |
 LL | |                                                      field2: SafeEnum::Variant1}};
    | |                                                                                ^- value is dropped here
    | |________________________________________________________________________________|
-   |                                                                                  statics cannot evaluate destructors
+   |                                                                                  the destructor for this type cannot be evaluated in statics
 
 error[E0010]: allocations are not allowed in statics
   --> $DIR/check-static-values-constraints.rs:79:33

src/test/ui/consts/const-eval/const_let.rs

@@ -14,16 +14,16 @@ const X2: FakeNeedsDrop = { let x; x = FakeNeedsDrop; x };
 
 // error
 const Y: FakeNeedsDrop = { let mut x = FakeNeedsDrop; x = FakeNeedsDrop; x };
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 // error
 const Y2: FakeNeedsDrop = { let mut x; x = FakeNeedsDrop; x = FakeNeedsDrop; x };
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 // error
 const Z: () = { let mut x = None; x = Some(FakeNeedsDrop); };
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 // error
 const Z2: () = { let mut x; x = None; x = Some(FakeNeedsDrop); };
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of

src/test/ui/consts/const-eval/const_let.stderr

@@ -1,34 +1,34 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `FakeNeedsDrop` cannot be evaluated at compile-time
   --> $DIR/const_let.rs:16:32
    |
 LL | const Y: FakeNeedsDrop = { let mut x = FakeNeedsDrop; x = FakeNeedsDrop; x };
    |                                ^^^^^                  - value is dropped here
    |                                |
-   |                                constants cannot evaluate destructors
+   |                                the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `FakeNeedsDrop` cannot be evaluated at compile-time
   --> $DIR/const_let.rs:20:33
    |
 LL | const Y2: FakeNeedsDrop = { let mut x; x = FakeNeedsDrop; x = FakeNeedsDrop; x };
    |                                 ^^^^^                     - value is dropped here
    |                                 |
-   |                                 constants cannot evaluate destructors
+   |                                 the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<FakeNeedsDrop>` cannot be evaluated at compile-time
   --> $DIR/const_let.rs:24:21
    |
 LL | const Z: () = { let mut x = None; x = Some(FakeNeedsDrop); };
    |                     ^^^^^                                  - value is dropped here
    |                     |
-   |                     constants cannot evaluate destructors
+   |                     the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<FakeNeedsDrop>` cannot be evaluated at compile-time
   --> $DIR/const_let.rs:28:22
    |
 LL | const Z2: () = { let mut x; x = None; x = Some(FakeNeedsDrop); };
    |                      ^^^^^                                     - value is dropped here
    |                      |
-   |                      constants cannot evaluate destructors
+   |                      the destructor for this type cannot be evaluated in constants
 
 error: aborting due to 4 previous errors
 

src/test/ui/consts/const-eval/issue-65394.rs

@@ -4,7 +4,7 @@
 // We will likely have to change this behavior before we allow `&mut` in a `const`.
 
 const _: Vec<i32> = {
-    let mut x = Vec::<i32>::new(); //~ ERROR destructors cannot be evaluated at compile-time
+    let mut x = Vec::<i32>::new(); //~ ERROR destructor of
     let r = &mut x; //~ ERROR mutable references are not allowed in constants
     let y = x;
     y

src/test/ui/consts/const-eval/issue-65394.stderr

@@ -7,11 +7,11 @@ LL |     let r = &mut x;
    = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
    = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Vec<i32>` cannot be evaluated at compile-time
   --> $DIR/issue-65394.rs:7:9
    |
 LL |     let mut x = Vec::<i32>::new();
-   |         ^^^^^ constants cannot evaluate destructors
+   |         ^^^^^ the destructor for this type cannot be evaluated in constants
 ...
 LL | };
    | - value is dropped here

src/test/ui/consts/const-eval/livedrop.rs

@@ -1,6 +1,6 @@
 const _: Option<Vec<i32>> = {
     let mut never_returned = Some(Vec::new());
-    let mut always_returned = None; //~ ERROR destructors cannot be evaluated at compile-time
+    let mut always_returned = None; //~ ERROR destructor of
 
     let mut i = 0;
     loop {

src/test/ui/consts/const-eval/livedrop.stderr

@@ -1,8 +1,8 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/livedrop.rs:3:9
    |
 LL |     let mut always_returned = None;
-   |         ^^^^^^^^^^^^^^^^^^^ constants cannot evaluate destructors
+   |         ^^^^^^^^^^^^^^^^^^^ the destructor for this type cannot be evaluated in constants
 ...
 LL |         always_returned = never_returned;
    |         --------------- value is dropped here

src/test/ui/consts/control-flow/drop-fail.precise.stderr

@@ -1,14 +1,14 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:8:9
    |
 LL |     let x = Some(Vec::new());
-   |         ^ constants cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:39:9
    |
 LL |     let mut tmp = None;
-   |         ^^^^^^^ constants cannot evaluate destructors
+   |         ^^^^^^^ the destructor for this type cannot be evaluated in constants
 
 error: aborting due to 2 previous errors
 

src/test/ui/consts/control-flow/drop-fail.rs

@@ -6,7 +6,7 @@
 const _: Option<Vec<i32>> = {
     let y: Option<Vec<i32>> = None;
     let x = Some(Vec::new());
-    //[stock,precise]~^ ERROR destructors cannot be evaluated at compile-time
+    //[stock,precise]~^ ERROR destructor of
 
     if true {
         x
@@ -19,7 +19,7 @@ const _: Option<Vec<i32>> = {
 // existing analysis.
 const _: Vec<i32> = {
     let vec_tuple = (Vec::new(),);
-    //[stock]~^ ERROR destructors cannot be evaluated at compile-time
+    //[stock]~^ ERROR destructor of
 
     vec_tuple.0
 };
@@ -27,7 +27,7 @@ const _: Vec<i32> = {
 // This applies to single-field enum variants as well.
 const _: Vec<i32> = {
     let x: Result<_, Vec<i32>> = Ok(Vec::new());
-    //[stock]~^ ERROR destructors cannot be evaluated at compile-time
+    //[stock]~^ ERROR destructor of
 
     match x {
         Ok(x) | Err(x) => x,
@@ -37,7 +37,7 @@ const _: Vec<i32> = {
 const _: Option<Vec<i32>> = {
     let mut some = Some(Vec::new());
     let mut tmp = None;
-    //[stock,precise]~^ ERROR destructors cannot be evaluated at compile-time
+    //[stock,precise]~^ ERROR destructor of
 
     let mut i = 0;
     while i < 10 {

src/test/ui/consts/control-flow/drop-fail.stock.stderr

@@ -1,35 +1,35 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:8:9
    |
 LL |     let x = Some(Vec::new());
-   |         ^ constants cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constants
 ...
 LL | };
    | - value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(Vec<i32>,)` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:21:9
    |
 LL |     let vec_tuple = (Vec::new(),);
-   |         ^^^^^^^^^ constants cannot evaluate destructors
+   |         ^^^^^^^^^ the destructor for this type cannot be evaluated in constants
 ...
 LL | };
    | - value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Result<Vec<i32>, Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:29:9
    |
 LL |     let x: Result<_, Vec<i32>> = Ok(Vec::new());
-   |         ^ constants cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constants
 ...
 LL | };
    | - value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<Vec<i32>>` cannot be evaluated at compile-time
   --> $DIR/drop-fail.rs:39:9
    |
 LL |     let mut tmp = None;
-   |         ^^^^^^^ constants cannot evaluate destructors
+   |         ^^^^^^^ the destructor for this type cannot be evaluated in constants
 ...
 LL | };
    | - value is dropped here

src/test/ui/consts/drop_box.rs

@@ -1,4 +1,4 @@
 const fn f<T>(_: Box<T>) {}
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 fn main() {}

src/test/ui/consts/drop_box.stderr

@@ -1,10 +1,10 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Box<T>` cannot be evaluated at compile-time
   --> $DIR/drop_box.rs:1:15
    |
 LL | const fn f<T>(_: Box<T>) {}
    |               ^           - value is dropped here
    |               |
-   |               constant functions cannot evaluate destructors
+   |               the destructor for this type cannot be evaluated in constant functions
 
 error: aborting due to previous error
 

src/test/ui/consts/drop_zst.stderr

@@ -1,8 +1,8 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `S` cannot be evaluated at compile-time
   --> $DIR/drop_zst.rs:14:9
    |
 LL |     let s = S;
-   |         ^ constant functions cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constant functions
 
 error: aborting due to previous error
 

src/test/ui/consts/min_const_fn/min_const_fn.rs

@@ -34,7 +34,7 @@ const fn foo35(a: bool, b: bool) -> bool { a ^ b }
 struct Foo<T: ?Sized>(T);
 impl<T> Foo<T> {
     const fn new(t: T) -> Self { Foo(t) }
-    const fn into_inner(self) -> T { self.0 } //~ destructors cannot be evaluated
+    const fn into_inner(self) -> T { self.0 } //~ destructor of
     const fn get(&self) -> &T { &self.0 }
     const fn get_mut(&mut self) -> &mut T { &mut self.0 }
     //~^ mutable references
@@ -43,7 +43,7 @@ impl<T> Foo<T> {
 }
 impl<'a, T> Foo<T> {
     const fn new_lt(t: T) -> Self { Foo(t) }
-    const fn into_inner_lt(self) -> T { self.0 } //~ destructors cannot be evaluated
+    const fn into_inner_lt(self) -> T { self.0 } //~ destructor of
     const fn get_lt(&'a self) -> &T { &self.0 }
     const fn get_mut_lt(&'a mut self) -> &mut T { &mut self.0 }
     //~^ mutable references
@@ -52,7 +52,7 @@ impl<'a, T> Foo<T> {
 }
 impl<T: Sized> Foo<T> {
     const fn new_s(t: T) -> Self { Foo(t) }
-    const fn into_inner_s(self) -> T { self.0 } //~ ERROR destructors
+    const fn into_inner_s(self) -> T { self.0 } //~ ERROR destructor
     const fn get_s(&self) -> &T { &self.0 }
     const fn get_mut_s(&mut self) -> &mut T { &mut self.0 }
     //~^ mutable references

src/test/ui/consts/min_const_fn/min_const_fn.stderr

@@ -1,10 +1,10 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Foo<T>` cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:37:25
    |
 LL |     const fn into_inner(self) -> T { self.0 }
    |                         ^^^^                - value is dropped here
    |                         |
-   |                         constant functions cannot evaluate destructors
+   |                         the destructor for this type cannot be evaluated in constant functions
 
 error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:39:22
@@ -33,13 +33,13 @@ LL |     const fn get_mut(&mut self) -> &mut T { &mut self.0 }
    = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
    = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Foo<T>` cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:46:28
    |
 LL |     const fn into_inner_lt(self) -> T { self.0 }
    |                            ^^^^                - value is dropped here
    |                            |
-   |                            constant functions cannot evaluate destructors
+   |                            the destructor for this type cannot be evaluated in constant functions
 
 error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:48:25
@@ -68,13 +68,13 @@ LL |     const fn get_mut_lt(&'a mut self) -> &mut T { &mut self.0 }
    = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
    = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Foo<T>` cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:55:27
    |
 LL |     const fn into_inner_s(self) -> T { self.0 }
    |                           ^^^^                - value is dropped here
    |                           |
-   |                           constant functions cannot evaluate destructors
+   |                           the destructor for this type cannot be evaluated in constant functions
 
 error[E0658]: mutable references are not allowed in constant functions
   --> $DIR/min_const_fn.rs:57:24
@@ -191,21 +191,21 @@ LL | const fn inc(x: &mut i32) { *x += 1 }
    = note: see issue #57349 <https://github.com/rust-lang/rust/issues/57349> for more information
    = help: add `#![feature(const_mut_refs)]` to the crate attributes to enable
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `AlanTuring<impl std::fmt::Debug>` cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:122:19
    |
 LL | const fn no_apit2(_x: AlanTuring<impl std::fmt::Debug>) {}
    |                   ^^                                     - value is dropped here
    |                   |
-   |                   constant functions cannot evaluate destructors
+   |                   the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `impl std::fmt::Debug` cannot be evaluated at compile-time
   --> $DIR/min_const_fn.rs:124:18
    |
 LL | const fn no_apit(_x: impl std::fmt::Debug) {}
    |                  ^^                         - value is dropped here
    |                  |
-   |                  constant functions cannot evaluate destructors
+   |                  the destructor for this type cannot be evaluated in constant functions
 
 error: aborting due to 24 previous errors
 

src/test/ui/consts/miri_unleashed/feature-gate-unleash_the_miri_inside_of_you.rs

@@ -8,7 +8,7 @@ trait Foo<T> {
 }
 
 trait Bar<T, U: Foo<T>> {
-    const F: u32 = (U::X, 42).1; //~ ERROR destructors cannot be evaluated at compile-time
+    const F: u32 = (U::X, 42).1; //~ ERROR destructor of
 }
 
 impl Foo<u32> for () {

src/test/ui/consts/miri_unleashed/feature-gate-unleash_the_miri_inside_of_you.stderr

@@ -1,10 +1,10 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(T, u32)` cannot be evaluated at compile-time
   --> $DIR/feature-gate-unleash_the_miri_inside_of_you.rs:11:20
    |
 LL |     const F: u32 = (U::X, 42).1;
    |                    ^^^^^^^^^^ - value is dropped here
    |                    |
-   |                    constants cannot evaluate destructors
+   |                    the destructor for this type cannot be evaluated in constants
 
 error: aborting due to previous error
 

src/test/ui/consts/qualif-indirect-mutation-fail.rs

@@ -6,13 +6,13 @@
 
 // Mutable borrow of a field with drop impl.
 pub const fn f() {
-    let mut a: (u32, Option<String>) = (0, None); //~ ERROR destructors cannot be evaluated
+    let mut a: (u32, Option<String>) = (0, None); //~ ERROR destructor of
     let _ = &mut a.1;
 }
 
 // Mutable borrow of a type with drop impl.
 pub const A1: () = {
-    let mut x = None; //~ ERROR destructors cannot be evaluated
+    let mut x = None; //~ ERROR destructor of
     let mut y = Some(String::new());
     let a = &mut x;
     let b = &mut y;
@@ -28,12 +28,12 @@ pub const A2: () = {
     let b = &mut y;
     std::mem::swap(a, b);
     std::mem::forget(y);
-    let _z = x; //~ ERROR destructors cannot be evaluated
+    let _z = x; //~ ERROR destructor of
 };
 
 // Shared borrow of a type that might be !Freeze and Drop.
 pub const fn g1<T>() {
-    let x: Option<T> = None; //~ ERROR destructors cannot be evaluated
+    let x: Option<T> = None; //~ ERROR destructor of
     let _ = x.is_some();
 }
 
@@ -41,24 +41,24 @@ pub const fn g1<T>() {
 pub const fn g2<T>() {
     let x: Option<T> = None;
     let _ = x.is_some();
-    let _y = x; //~ ERROR destructors cannot be evaluated
+    let _y = x; //~ ERROR destructor of
 }
 
 // Mutable raw reference to a Drop type.
 pub const fn address_of_mut() {
-    let mut x: Option<String> = None; //~ ERROR destructors cannot be evaluated
+    let mut x: Option<String> = None; //~ ERROR destructor of
     &raw mut x;
 
-    let mut y: Option<String> = None; //~ ERROR destructors cannot be evaluated
+    let mut y: Option<String> = None; //~ ERROR destructor of
     std::ptr::addr_of_mut!(y);
 }
 
 // Const raw reference to a Drop type. Conservatively assumed to allow mutation
 // until resolution of https://github.com/rust-lang/rust/issues/56604.
 pub const fn address_of_const() {
-    let x: Option<String> = None; //~ ERROR destructors cannot be evaluated
+    let x: Option<String> = None; //~ ERROR destructor of
     &raw const x;
 
-    let y: Option<String> = None; //~ ERROR destructors cannot be evaluated
+    let y: Option<String> = None; //~ ERROR destructor of
     std::ptr::addr_of!(y);
 }

src/test/ui/consts/qualif-indirect-mutation-fail.stderr

@@ -1,56 +1,56 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(u32, Option<String>)` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:9:9
    |
 LL |     let mut a: (u32, Option<String>) = (0, None);
-   |         ^^^^^ constant functions cannot evaluate destructors
+   |         ^^^^^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:15:9
    |
 LL |     let mut x = None;
-   |         ^^^^^ constants cannot evaluate destructors
+   |         ^^^^^ the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:31:9
    |
 LL |     let _z = x;
-   |         ^^ constants cannot evaluate destructors
+   |         ^^ the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<T>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:36:9
    |
 LL |     let x: Option<T> = None;
-   |         ^ constant functions cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<T>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:44:9
    |
 LL |     let _y = x;
-   |         ^^ constant functions cannot evaluate destructors
+   |         ^^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:52:9
    |
 LL |     let mut y: Option<String> = None;
-   |         ^^^^^ constant functions cannot evaluate destructors
+   |         ^^^^^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:49:9
    |
 LL |     let mut x: Option<String> = None;
-   |         ^^^^^ constant functions cannot evaluate destructors
+   |         ^^^^^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:62:9
    |
 LL |     let y: Option<String> = None;
-   |         ^ constant functions cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Option<String>` cannot be evaluated at compile-time
   --> $DIR/qualif-indirect-mutation-fail.rs:59:9
    |
 LL |     let x: Option<String> = None;
-   |         ^ constant functions cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in constant functions
 
 error: aborting due to 9 previous errors
 

src/test/ui/consts/stable-precise-live-drops-in-libcore.rs

@@ -11,7 +11,7 @@ impl<T> Either<T, T> {
     #[stable(feature = "rust1", since = "1.0.0")]
     #[rustc_const_stable(feature = "foo", since = "1.0.0")]
     pub const fn unwrap(self) -> T {
-        //~^ ERROR destructors cannot be evaluated at compile-time
+        //~^ ERROR destructor of
         match self {
             Self::Left(t) => t,
             Self::Right(t) => t,

src/test/ui/consts/stable-precise-live-drops-in-libcore.stderr

@@ -1,8 +1,8 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Either<T, T>` cannot be evaluated at compile-time
   --> $DIR/stable-precise-live-drops-in-libcore.rs:13:25
    |
 LL |     pub const fn unwrap(self) -> T {
-   |                         ^^^^ constant functions cannot evaluate destructors
+   |                         ^^^^ the destructor for this type cannot be evaluated in constant functions
 ...
 LL |     }
    |     - value is dropped here

src/test/ui/consts/unstable-const-fn-in-libcore.rs

@@ -15,8 +15,8 @@ impl<T> Opt<T> {
     #[rustc_const_unstable(feature = "foo", issue = "none")]
     #[stable(feature = "rust1", since = "1.0.0")]
     const fn unwrap_or_else<F: ~const FnOnce() -> T>(self, f: F) -> T {
-    //~^ ERROR destructors cannot be evaluated at compile-time
+    //~^ ERROR destructor of
-    //~| ERROR destructors cannot be evaluated at compile-time
+    //~| ERROR destructor of
         match self {
             Opt::Some(t) => t,
             Opt::None => f(),

src/test/ui/consts/unstable-const-fn-in-libcore.stderr

@@ -1,17 +1,17 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `F` cannot be evaluated at compile-time
   --> $DIR/unstable-const-fn-in-libcore.rs:17:60
    |
 LL |     const fn unwrap_or_else<F: ~const FnOnce() -> T>(self, f: F) -> T {
-   |                                                            ^ constant functions cannot evaluate destructors
+   |                                                            ^ the destructor for this type cannot be evaluated in constant functions
 ...
 LL |     }
    |     - value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `Opt<T>` cannot be evaluated at compile-time
   --> $DIR/unstable-const-fn-in-libcore.rs:17:54
    |
 LL |     const fn unwrap_or_else<F: ~const FnOnce() -> T>(self, f: F) -> T {
-   |                                                      ^^^^ constant functions cannot evaluate destructors
+   |                                                      ^^^^ the destructor for this type cannot be evaluated in constant functions
 ...
 LL |     }
    |     - value is dropped here

src/test/ui/drop/repeat-drop-2.rs

@@ -5,7 +5,7 @@ fn borrowck_catch() {
 }
 
 const _: [String; 0] = [String::new(); 0];
-//~^ ERROR destructors cannot be evaluated at compile-time [E0493]
+//~^ ERROR destructor of `String` cannot be evaluated at compile-time [E0493]
 
 fn must_be_init() {
     let x: u8;

src/test/ui/drop/repeat-drop-2.stderr

@@ -8,13 +8,13 @@ LL |     let _bar = foo;
 LL |     let _baz = [foo; 0];
    |                 ^^^ value used here after move
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `String` cannot be evaluated at compile-time
   --> $DIR/repeat-drop-2.rs:7:25
    |
 LL | const _: [String; 0] = [String::new(); 0];
    |                        -^^^^^^^^^^^^^----
    |                        ||
-   |                        |constants cannot evaluate destructors
+   |                        |the destructor for this type cannot be evaluated in constants
    |                        value is dropped here
 
 error[E0381]: used binding `x` isn't initialized

src/test/ui/impl-trait/issues/issue-78722.rs

@@ -12,7 +12,7 @@ struct Bug {
         }
         let f: F = async { 1 };
         //~^ ERROR `async` blocks are not allowed in constants
-        //~| ERROR destructors cannot be evaluated at compile-time
+        //~| ERROR destructor of
         1
     }],
 }

src/test/ui/impl-trait/issues/issue-78722.stderr

@@ -7,11 +7,11 @@ LL |         let f: F = async { 1 };
    = note: see issue #85368 <https://github.com/rust-lang/rust/issues/85368> for more information
    = help: add `#![feature(const_async_blocks)]` to the crate attributes to enable
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `F` cannot be evaluated at compile-time
   --> $DIR/issue-78722.rs:13:13
    |
 LL |         let f: F = async { 1 };
-   |             ^ constants cannot evaluate destructors
+   |             ^ the destructor for this type cannot be evaluated in constants
 ...
 LL |     }],
    |     - value is dropped here

src/test/ui/mir/drop-elaboration-after-borrowck-error.rs

@@ -3,9 +3,9 @@
 
 static A: () = {
     let a: [String; 1];
-    //~^ ERROR destructors cannot be evaluated at compile-time
+    //~^ ERROR destructor of
     a[0] = String::new();
-    //~^ ERROR destructors cannot be evaluated at compile-time
+    //~^ ERROR destructor of
     //~| ERROR binding `a` isn't initialized
 };
 
@@ -14,9 +14,9 @@ struct B<T>([T; 1]);
 impl<T> B<T> {
     pub const fn f(mut self, other: T) -> Self {
         let _this = self;
-        //~^ ERROR destructors cannot be evaluated at compile-time
+        //~^ ERROR destructor of
         self.0[0] = other;
-        //~^ ERROR destructors cannot be evaluated at compile-time
+        //~^ ERROR destructor of
         //~| ERROR use of moved value
         self
     }

src/test/ui/mir/drop-elaboration-after-borrowck-error.stderr

@@ -1,17 +1,17 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `String` cannot be evaluated at compile-time
   --> $DIR/drop-elaboration-after-borrowck-error.rs:7:5
    |
 LL |     a[0] = String::new();
    |     ^^^^
    |     |
-   |     statics cannot evaluate destructors
+   |     the destructor for this type cannot be evaluated in statics
    |     value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `[String; 1]` cannot be evaluated at compile-time
   --> $DIR/drop-elaboration-after-borrowck-error.rs:5:9
    |
 LL |     let a: [String; 1];
-   |         ^ statics cannot evaluate destructors
+   |         ^ the destructor for this type cannot be evaluated in statics
 ...
 LL | };
    | - value is dropped here
@@ -25,20 +25,20 @@ LL |
 LL |     a[0] = String::new();
    |     ^^^^ `a` used here but it isn't initialized
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/drop-elaboration-after-borrowck-error.rs:18:9
    |
 LL |         self.0[0] = other;
    |         ^^^^^^^^^
    |         |
-   |         constant functions cannot evaluate destructors
+   |         the destructor for this type cannot be evaluated in constant functions
    |         value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `B<T>` cannot be evaluated at compile-time
   --> $DIR/drop-elaboration-after-borrowck-error.rs:16:13
    |
 LL |         let _this = self;
-   |             ^^^^^ constant functions cannot evaluate destructors
+   |             ^^^^^ the destructor for this type cannot be evaluated in constant functions
 ...
 LL |     }
    |     - value is dropped here

src/test/ui/span/E0493.rs

@@ -15,7 +15,7 @@ impl Drop for Bar {
 }
 
 const F : Foo = (Foo { a : 0 }, Foo { a : 1 }).1;
-//~^ destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 fn main() {
 }

src/test/ui/span/E0493.stderr

@@ -1,10 +1,10 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(Foo, Foo)` cannot be evaluated at compile-time
   --> $DIR/E0493.rs:17:17
    |
 LL | const F : Foo = (Foo { a : 0 }, Foo { a : 1 }).1;
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - value is dropped here
    |                 |
-   |                 constants cannot evaluate destructors
+   |                 the destructor for this type cannot be evaluated in constants
 
 error: aborting due to previous error
 

src/test/ui/static/static-drop-scope.rs

@@ -5,33 +5,33 @@ impl Drop for WithDtor {
 }
 
 static PROMOTION_FAIL_S: Option<&'static WithDtor> = Some(&WithDtor);
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 //~| ERROR temporary value dropped while borrowed
 
 const PROMOTION_FAIL_C: Option<&'static WithDtor> = Some(&WithDtor);
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 //~| ERROR temporary value dropped while borrowed
 
 static EARLY_DROP_S: i32 = (WithDtor, 0).1;
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 const EARLY_DROP_C: i32 = (WithDtor, 0).1;
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 const fn const_drop<T>(_: T) {}
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 const fn const_drop2<T>(x: T) {
     (x, ()).1
-    //~^ ERROR destructors cannot be evaluated at compile-time
+    //~^ ERROR destructor of
 }
 
 const EARLY_DROP_C_OPTION: i32 = (Some(WithDtor), 0).1;
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 const HELPER: Option<WithDtor> = Some(WithDtor);
 
 const EARLY_DROP_C_OPTION_CONSTANT: i32 = (HELPER, 0).1;
-//~^ ERROR destructors cannot be evaluated at compile-time
+//~^ ERROR destructor of
 
 fn main () {}

src/test/ui/static/static-drop-scope.stderr

@@ -1,10 +1,10 @@
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `WithDtor` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:7:60
    |
 LL | static PROMOTION_FAIL_S: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                            ^^^^^^^^- value is dropped here
    |                                                            |
-   |                                                            statics cannot evaluate destructors
+   |                                                            the destructor for this type cannot be evaluated in statics
 
 error[E0716]: temporary value dropped while borrowed
   --> $DIR/static-drop-scope.rs:7:60
@@ -16,13 +16,13 @@ LL | static PROMOTION_FAIL_S: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                      |     creates a temporary which is freed while still in use
    |                                                      using this value as a static requires that borrow lasts for `'static`
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `WithDtor` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:11:59
    |
 LL | const PROMOTION_FAIL_C: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                           ^^^^^^^^- value is dropped here
    |                                                           |
-   |                                                           constants cannot evaluate destructors
+   |                                                           the destructor for this type cannot be evaluated in constants
 
 error[E0716]: temporary value dropped while borrowed
   --> $DIR/static-drop-scope.rs:11:59
@@ -34,54 +34,54 @@ LL | const PROMOTION_FAIL_C: Option<&'static WithDtor> = Some(&WithDtor);
    |                                                     |     creates a temporary which is freed while still in use
    |                                                     using this value as a constant requires that borrow lasts for `'static`
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(WithDtor, i32)` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:15:28
    |
 LL | static EARLY_DROP_S: i32 = (WithDtor, 0).1;
    |                            ^^^^^^^^^^^^^ - value is dropped here
    |                            |
-   |                            statics cannot evaluate destructors
+   |                            the destructor for this type cannot be evaluated in statics
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(WithDtor, i32)` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:18:27
    |
 LL | const EARLY_DROP_C: i32 = (WithDtor, 0).1;
    |                           ^^^^^^^^^^^^^ - value is dropped here
    |                           |
-   |                           constants cannot evaluate destructors
+   |                           the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:21:24
    |
 LL | const fn const_drop<T>(_: T) {}
    |                        ^      - value is dropped here
    |                        |
-   |                        constant functions cannot evaluate destructors
+   |                        the destructor for this type cannot be evaluated in constant functions
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(T, ())` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:25:5
    |
 LL |     (x, ()).1
-   |     ^^^^^^^ constant functions cannot evaluate destructors
+   |     ^^^^^^^ the destructor for this type cannot be evaluated in constant functions
 LL |
 LL | }
    | - value is dropped here
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(Option<WithDtor>, i32)` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:29:34
    |
 LL | const EARLY_DROP_C_OPTION: i32 = (Some(WithDtor), 0).1;
    |                                  ^^^^^^^^^^^^^^^^^^^ - value is dropped here
    |                                  |
-   |                                  constants cannot evaluate destructors
+   |                                  the destructor for this type cannot be evaluated in constants
 
-error[E0493]: destructors cannot be evaluated at compile-time
+error[E0493]: destructor of `(Option<WithDtor>, i32)` cannot be evaluated at compile-time
   --> $DIR/static-drop-scope.rs:34:43
    |
 LL | const EARLY_DROP_C_OPTION_CONSTANT: i32 = (HELPER, 0).1;
    |                                           ^^^^^^^^^^^ - value is dropped here
    |                                           |
-   |                                           constants cannot evaluate destructors
+   |                                           the destructor for this type cannot be evaluated in constants
 
 error: aborting due to 10 previous errors