Auto merge of #94934 - Lireer:const-prop-lint, r=oli-obk

Separate const prop lints from optimizations

r? `@oli-obk`

Separates lints and optimizations during const prop by moving the lints into their own file and checking them during post borrowck cleanup.
Thanks to `@oli-obk` for mentoring me.

27 files changed, 248 insertions, 62 deletions

diff --git a/src/test/codegen/consts.rs b/src/test/codegen/consts.rs
index 1a84f1a4479..e6afbe49864 100644
--- a/src/test/codegen/consts.rs
+++ b/src/test/codegen/consts.rs
@@ -10,7 +10,7 @@
 // CHECK: @STATIC = {{.*}}, align 4
 
 // This checks the constants from inline_enum_const
-// CHECK: @alloc9 = {{.*}}, align 2
+// CHECK: @alloc12 = {{.*}}, align 2
 
 // This checks the constants from {low,high}_align_const, they share the same
 // constant, but the alignment differs, so the higher one should be used
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.rs b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.rs
index be8162c86b9..0315938a7ed 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.rs
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.rs
@@ -4,12 +4,12 @@ trait Foo {
     const BAR: u32;
 }
 
-const IMPL_REF_BAR: u32 = GlobalImplRef::BAR; //~ ERROR E0391
+const IMPL_REF_BAR: u32 = GlobalImplRef::BAR;
 
 struct GlobalImplRef;
 
 impl GlobalImplRef {
-    const BAR: u32 = IMPL_REF_BAR;
+    const BAR: u32 = IMPL_REF_BAR; //~ ERROR E0391
 }
 
 fn main() {}
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.stderr b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.stderr
index 61b16cb9d58..3d696bb049c 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.stderr
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-impl.stderr
@@ -1,9 +1,15 @@
-error[E0391]: cycle detected when simplifying constant for the type system `IMPL_REF_BAR`
+error[E0391]: cycle detected when elaborating drops for `<impl at $DIR/issue-24949-assoc-const-static-recursion-impl.rs:11:1: 13:2>::BAR`
+  --> $DIR/issue-24949-assoc-const-static-recursion-impl.rs:12:5
+   |
+LL |     const BAR: u32 = IMPL_REF_BAR;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: ...which requires normalizing `IMPL_REF_BAR`...
+note: ...which requires simplifying constant for the type system `IMPL_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-impl.rs:7:1
    |
 LL | const IMPL_REF_BAR: u32 = GlobalImplRef::BAR;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
 note: ...which requires simplifying constant for the type system `IMPL_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-impl.rs:7:1
    |
@@ -35,8 +41,7 @@ note: ...which requires caching mir of `<impl at $DIR/issue-24949-assoc-const-st
    |
 LL |     const BAR: u32 = IMPL_REF_BAR;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which requires normalizing `IMPL_REF_BAR`...
-   = note: ...which again requires simplifying constant for the type system `IMPL_REF_BAR`, completing the cycle
+   = note: ...which again requires elaborating drops for `<impl at $DIR/issue-24949-assoc-const-static-recursion-impl.rs:11:1: 13:2>::BAR`, completing the cycle
    = note: cycle used when running analysis passes on this crate
 
 error: aborting due to previous error
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.rs b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.rs
index cec75ae19f4..4e89f686288 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.rs
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.rs
@@ -5,10 +5,10 @@ trait Foo {
 }
 
 trait FooDefault {
-    const BAR: u32 = DEFAULT_REF_BAR;
+    const BAR: u32 = DEFAULT_REF_BAR; //~ ERROR E0391
 }
 
-const DEFAULT_REF_BAR: u32 = <GlobalDefaultRef>::BAR; //~ ERROR E0391
+const DEFAULT_REF_BAR: u32 = <GlobalDefaultRef>::BAR;
 
 struct GlobalDefaultRef;
 
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.stderr b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.stderr
index 494dc0c0ed4..71e26245e16 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.stderr
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait-default.stderr
@@ -1,9 +1,15 @@
-error[E0391]: cycle detected when simplifying constant for the type system `DEFAULT_REF_BAR`
+error[E0391]: cycle detected when elaborating drops for `FooDefault::BAR`
+  --> $DIR/issue-24949-assoc-const-static-recursion-trait-default.rs:8:5
+   |
+LL |     const BAR: u32 = DEFAULT_REF_BAR;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: ...which requires normalizing `DEFAULT_REF_BAR`...
+note: ...which requires simplifying constant for the type system `DEFAULT_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-trait-default.rs:11:1
    |
 LL | const DEFAULT_REF_BAR: u32 = <GlobalDefaultRef>::BAR;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
 note: ...which requires simplifying constant for the type system `DEFAULT_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-trait-default.rs:11:1
    |
@@ -35,8 +41,7 @@ note: ...which requires caching mir of `FooDefault::BAR` for CTFE...
    |
 LL |     const BAR: u32 = DEFAULT_REF_BAR;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which requires normalizing `DEFAULT_REF_BAR`...
-   = note: ...which again requires simplifying constant for the type system `DEFAULT_REF_BAR`, completing the cycle
+   = note: ...which again requires elaborating drops for `FooDefault::BAR`, completing the cycle
    = note: cycle used when running analysis passes on this crate
 
 error: aborting due to previous error
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.rs b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.rs
index 62af8534340..68b653ff3c5 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.rs
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.rs
@@ -4,12 +4,12 @@ trait Foo {
     const BAR: u32;
 }
 
-const TRAIT_REF_BAR: u32 = <GlobalTraitRef>::BAR; //~ ERROR E0391
+const TRAIT_REF_BAR: u32 = <GlobalTraitRef>::BAR;
 
 struct GlobalTraitRef;
 
 impl Foo for GlobalTraitRef {
-    const BAR: u32 = TRAIT_REF_BAR;
+    const BAR: u32 = TRAIT_REF_BAR; //~ ERROR E0391
 }
 
 fn main() {}
diff --git a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.stderr b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.stderr
index 4ff253bffcb..020d758e153 100644
--- a/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.stderr
+++ b/src/test/ui/associated-consts/issue-24949-assoc-const-static-recursion-trait.stderr
@@ -1,9 +1,15 @@
-error[E0391]: cycle detected when simplifying constant for the type system `TRAIT_REF_BAR`
+error[E0391]: cycle detected when elaborating drops for `<impl at $DIR/issue-24949-assoc-const-static-recursion-trait.rs:11:1: 13:2>::BAR`
+  --> $DIR/issue-24949-assoc-const-static-recursion-trait.rs:12:5
+   |
+LL |     const BAR: u32 = TRAIT_REF_BAR;
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   |
+   = note: ...which requires normalizing `TRAIT_REF_BAR`...
+note: ...which requires simplifying constant for the type system `TRAIT_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-trait.rs:7:1
    |
 LL | const TRAIT_REF_BAR: u32 = <GlobalTraitRef>::BAR;
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
 note: ...which requires simplifying constant for the type system `TRAIT_REF_BAR`...
   --> $DIR/issue-24949-assoc-const-static-recursion-trait.rs:7:1
    |
@@ -35,8 +41,7 @@ note: ...which requires caching mir of `<impl at $DIR/issue-24949-assoc-const-st
    |
 LL |     const BAR: u32 = TRAIT_REF_BAR;
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which requires normalizing `TRAIT_REF_BAR`...
-   = note: ...which again requires simplifying constant for the type system `TRAIT_REF_BAR`, completing the cycle
+   = note: ...which again requires elaborating drops for `<impl at $DIR/issue-24949-assoc-const-static-recursion-trait.rs:11:1: 13:2>::BAR`, completing the cycle
    = note: cycle used when running analysis passes on this crate
 
 error: aborting due to previous error
diff --git a/src/test/ui/const_prop/inline_spans.rs b/src/test/ui/const_prop/inline_spans.rs
index f1cfcfee557..504f2781156 100644
--- a/src/test/ui/const_prop/inline_spans.rs
+++ b/src/test/ui/const_prop/inline_spans.rs
@@ -1,18 +1,15 @@
-// build-fail
+// build-pass
 // compile-flags: -Zmir-opt-level=3
+// Overflow can't be detected by const prop
+// could only be detected after optimizations
 
 #![deny(warnings)]
 
 fn main() {
     let _ = add(u8::MAX, 1);
-    //~^ NOTE in this expansion of inlined source
-    //~| NOTE in this expansion of inlined source
 }
 
 #[inline(always)]
 fn add(x: u8, y: u8) -> u8 {
     x + y
-    //~^ ERROR this arithmetic operation will overflow
-    //~| NOTE attempt to compute `u8::MAX + 1_u8`, which would overflow
-    //~| NOTE `#[deny(arithmetic_overflow)]` on by default
 }
diff --git a/src/test/ui/const_prop/inline_spans.stderr b/src/test/ui/const_prop/inline_spans.stderr
deleted file mode 100644
index f99a3142386..00000000000
--- a/src/test/ui/const_prop/inline_spans.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error: this arithmetic operation will overflow
-  --> $DIR/inline_spans.rs:14:5
-   |
-LL |     let _ = add(u8::MAX, 1);
-   |             --------------- in this inlined function call
-...
-LL |     x + y
-   |     ^^^^^ attempt to compute `u8::MAX + 1_u8`, which would overflow
-   |
-   = note: `#[deny(arithmetic_overflow)]` on by default
-
-error: aborting due to previous error
-
diff --git a/src/test/ui/consts/const-eval/const-eval-query-stack.stderr b/src/test/ui/consts/const-eval/const-eval-query-stack.stderr
index 45a3d901c98..8bd5c08dc46 100644
--- a/src/test/ui/consts/const-eval/const-eval-query-stack.stderr
+++ b/src/test/ui/consts/const-eval/const-eval-query-stack.stderr
@@ -21,6 +21,7 @@ LL |     let x: &'static i32 = &X;
    |                            ^ referenced constant has errors
 query stack during panic:
 #0 [try_normalize_mir_const_after_erasing_regions] normalizing `main::promoted[1]`
-#1 [optimized_mir] optimizing MIR for `main`
-#2 [collect_and_partition_mono_items] collect_and_partition_mono_items
+#1 [mir_drops_elaborated_and_const_checked] elaborating drops for `main`
+#2 [optimized_mir] optimizing MIR for `main`
+#3 [collect_and_partition_mono_items] collect_and_partition_mono_items
 end of query stack
diff --git a/src/test/ui/consts/const-eval/issue-49296.stderr b/src/test/ui/consts/const-eval/issue-49296.stderr
index 1864a284579..cc4f1594c32 100644
--- a/src/test/ui/consts/const-eval/issue-49296.stderr
+++ b/src/test/ui/consts/const-eval/issue-49296.stderr
@@ -2,7 +2,7 @@ error[E0080]: evaluation of constant value failed
   --> $DIR/issue-49296.rs:9:16
    |
 LL | const X: u64 = *wat(42);
-   |                ^^^^^^^^ pointer to alloc2 was dereferenced after this allocation got freed
+   |                ^^^^^^^^ pointer to alloc3 was dereferenced after this allocation got freed
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/consts/const-eval/panic-assoc-never-type.rs b/src/test/ui/consts/const-eval/panic-assoc-never-type.rs
index 2bdf5d54765..80b0a1432fb 100644
--- a/src/test/ui/consts/const-eval/panic-assoc-never-type.rs
+++ b/src/test/ui/consts/const-eval/panic-assoc-never-type.rs
@@ -13,4 +13,5 @@ impl PrintName {
 
 fn main() {
     let _ = PrintName::VOID;
+    //~^ ERROR erroneous constant used [E0080]
 }
diff --git a/src/test/ui/consts/const-eval/panic-assoc-never-type.stderr b/src/test/ui/consts/const-eval/panic-assoc-never-type.stderr
index 9631b7748b5..0116a83910d 100644
--- a/src/test/ui/consts/const-eval/panic-assoc-never-type.stderr
+++ b/src/test/ui/consts/const-eval/panic-assoc-never-type.stderr
@@ -6,6 +6,12 @@ LL |     const VOID: ! = panic!();
    |
    = note: this error originates in the macro `$crate::panic::panic_2015` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to previous error
+error[E0080]: erroneous constant used
+  --> $DIR/panic-assoc-never-type.rs:15:13
+   |
+LL |     let _ = PrintName::VOID;
+   |             ^^^^^^^^^^^^^^^ referenced constant has errors
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0080`.
diff --git a/src/test/ui/consts/const-eval/promoted_errors.noopt.stderr b/src/test/ui/consts/const-eval/promoted_errors.noopt.stderr
index 77e7d484071..5bfd4ef92a9 100644
--- a/src/test/ui/consts/const-eval/promoted_errors.noopt.stderr
+++ b/src/test/ui/consts/const-eval/promoted_errors.noopt.stderr
@@ -1,3 +1,45 @@
+warning: this arithmetic operation will overflow
+  --> $DIR/promoted_errors.rs:15:5
+   |
+LL |     0 - 1
+   |     ^^^^^ attempt to compute `0_u32 - 1_u32`, which would overflow
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:20
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                    ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:21:5
+   |
+LL |     1 / 0
+   |     ^^^^^ attempt to divide `1_i32` by zero
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:41
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                                         ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:27:5
+   |
+LL |     1 / (1 - 1)
+   |     ^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:31:5
+   |
+LL |     1 / (false as i32)
+   |     ^^^^^^^^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:35:5
+   |
+LL |     [1, 2, 3][4]
+   |     ^^^^^^^^^^^^ index out of bounds: the length is 3 but the index is 4
+
 warning: any use of this value will cause an error
   --> $DIR/promoted_errors.rs:15:5
    |
@@ -6,7 +48,7 @@ LL |       0 - 1
    |       |
    |       attempt to compute `0_u32 - 1_u32`, which would overflow
    |       inside `overflow` at $DIR/promoted_errors.rs:15:5
-   |       inside `X` at $DIR/promoted_errors.rs:38:29
+   |       inside `X` at $DIR/promoted_errors.rs:43:29
 ...
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -26,7 +68,7 @@ LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
 warning: any use of this value will cause an error
-  --> $DIR/promoted_errors.rs:38:28
+  --> $DIR/promoted_errors.rs:43:28
    |
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -41,5 +83,5 @@ LL | | };
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
-warning: 2 warnings emitted
+warning: 7 warnings emitted
 
diff --git a/src/test/ui/consts/const-eval/promoted_errors.opt.stderr b/src/test/ui/consts/const-eval/promoted_errors.opt.stderr
index 6b17346e6ec..0a8a8aef3cf 100644
--- a/src/test/ui/consts/const-eval/promoted_errors.opt.stderr
+++ b/src/test/ui/consts/const-eval/promoted_errors.opt.stderr
@@ -1,12 +1,54 @@
+warning: this arithmetic operation will overflow
+  --> $DIR/promoted_errors.rs:15:5
+   |
+LL |     0 - 1
+   |     ^^^^^ attempt to compute `0_u32 - 1_u32`, which would overflow
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:20
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                    ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:21:5
+   |
+LL |     1 / 0
+   |     ^^^^^ attempt to divide `1_i32` by zero
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:41
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                                         ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:27:5
+   |
+LL |     1 / (1 - 1)
+   |     ^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:31:5
+   |
+LL |     1 / (false as i32)
+   |     ^^^^^^^^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:35:5
+   |
+LL |     [1, 2, 3][4]
+   |     ^^^^^^^^^^^^ index out of bounds: the length is 3 but the index is 4
+
 warning: any use of this value will cause an error
-  --> $DIR/promoted_errors.rs:20:5
+  --> $DIR/promoted_errors.rs:21:5
    |
 LL |       1 / 0
    |       ^^^^^
    |       |
    |       attempt to divide `1_i32` by zero
-   |       inside `div_by_zero1` at $DIR/promoted_errors.rs:20:5
-   |       inside `X` at $DIR/promoted_errors.rs:41:29
+   |       inside `div_by_zero1` at $DIR/promoted_errors.rs:21:5
+   |       inside `X` at $DIR/promoted_errors.rs:46:29
 ...
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -26,7 +68,7 @@ LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
 warning: any use of this value will cause an error
-  --> $DIR/promoted_errors.rs:41:28
+  --> $DIR/promoted_errors.rs:46:28
    |
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -42,5 +84,5 @@ LL | | };
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
-warning: 2 warnings emitted
+warning: 7 warnings emitted
 
diff --git a/src/test/ui/consts/const-eval/promoted_errors.opt_with_overflow_checks.stderr b/src/test/ui/consts/const-eval/promoted_errors.opt_with_overflow_checks.stderr
index 77e7d484071..5bfd4ef92a9 100644
--- a/src/test/ui/consts/const-eval/promoted_errors.opt_with_overflow_checks.stderr
+++ b/src/test/ui/consts/const-eval/promoted_errors.opt_with_overflow_checks.stderr
@@ -1,3 +1,45 @@
+warning: this arithmetic operation will overflow
+  --> $DIR/promoted_errors.rs:15:5
+   |
+LL |     0 - 1
+   |     ^^^^^ attempt to compute `0_u32 - 1_u32`, which would overflow
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:20
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                    ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:21:5
+   |
+LL |     1 / 0
+   |     ^^^^^ attempt to divide `1_i32` by zero
+   |
+note: the lint level is defined here
+  --> $DIR/promoted_errors.rs:11:41
+   |
+LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
+   |                                         ^^^^^^^^^^^^^^^^^^^
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:27:5
+   |
+LL |     1 / (1 - 1)
+   |     ^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:31:5
+   |
+LL |     1 / (false as i32)
+   |     ^^^^^^^^^^^^^^^^^^ attempt to divide `1_i32` by zero
+
+warning: this operation will panic at runtime
+  --> $DIR/promoted_errors.rs:35:5
+   |
+LL |     [1, 2, 3][4]
+   |     ^^^^^^^^^^^^ index out of bounds: the length is 3 but the index is 4
+
 warning: any use of this value will cause an error
   --> $DIR/promoted_errors.rs:15:5
    |
@@ -6,7 +48,7 @@ LL |       0 - 1
    |       |
    |       attempt to compute `0_u32 - 1_u32`, which would overflow
    |       inside `overflow` at $DIR/promoted_errors.rs:15:5
-   |       inside `X` at $DIR/promoted_errors.rs:38:29
+   |       inside `X` at $DIR/promoted_errors.rs:43:29
 ...
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -26,7 +68,7 @@ LL | #![warn(const_err, arithmetic_overflow, unconditional_panic)]
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
 warning: any use of this value will cause an error
-  --> $DIR/promoted_errors.rs:38:28
+  --> $DIR/promoted_errors.rs:43:28
    |
 LL | / const X: () = {
 LL | |     let _x: &'static u32 = &overflow();
@@ -41,5 +83,5 @@ LL | | };
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
 
-warning: 2 warnings emitted
+warning: 7 warnings emitted
 
diff --git a/src/test/ui/consts/const-eval/promoted_errors.rs b/src/test/ui/consts/const-eval/promoted_errors.rs
index 5bafea1ed46..eb891de33c4 100644
--- a/src/test/ui/consts/const-eval/promoted_errors.rs
+++ b/src/test/ui/consts/const-eval/promoted_errors.rs
@@ -15,20 +15,25 @@ const fn overflow() -> u32 {
     0 - 1
     //[opt_with_overflow_checks,noopt]~^ WARN any use of this value will cause an error
     //[opt_with_overflow_checks,noopt]~| WARN this was previously accepted by the compiler
+    //~^^^ WARN this arithmetic operation will overflow
 }
 const fn div_by_zero1() -> i32 {
     1 / 0
     //[opt]~^ WARN any use of this value will cause an error
     //[opt]~| WARN this was previously accepted by the compiler but is being phased out
+    //~^^^ WARN this operation will panic at runtime
 }
 const fn div_by_zero2() -> i32 {
     1 / (1 - 1)
+    //~^ WARN this operation will panic at runtime
 }
 const fn div_by_zero3() -> i32 {
     1 / (false as i32)
+    //~^ WARN this operation will panic at runtime
 }
 const fn oob() -> i32 {
     [1, 2, 3][4]
+    //~^ WARN this operation will panic at runtime
 }
 
 // An unused constant containing failing promoteds.
diff --git a/src/test/ui/consts/const-eval/union-const-eval-field.rs b/src/test/ui/consts/const-eval/union-const-eval-field.rs
index 80263718330..a1e48cac4fa 100644
--- a/src/test/ui/consts/const-eval/union-const-eval-field.rs
+++ b/src/test/ui/consts/const-eval/union-const-eval-field.rs
@@ -28,6 +28,7 @@ const fn read_field3() -> Field3 {
     const FIELD3: Field3 = unsafe { UNION.field3 };
     //~^ ERROR it is undefined behavior to use this value
     FIELD3
+    //~^ ERROR erroneous constant used [E0080]
 }
 
 fn main() {
diff --git a/src/test/ui/consts/const-eval/union-const-eval-field.stderr b/src/test/ui/consts/const-eval/union-const-eval-field.stderr
index e5a107ff011..8f818462781 100644
--- a/src/test/ui/consts/const-eval/union-const-eval-field.stderr
+++ b/src/test/ui/consts/const-eval/union-const-eval-field.stderr
@@ -9,6 +9,12 @@ LL |     const FIELD3: Field3 = unsafe { UNION.field3 };
                __ __ __ __ __ __ __ __                         │ ░░░░░░░░
            }
 
-error: aborting due to previous error
+error[E0080]: erroneous constant used
+  --> $DIR/union-const-eval-field.rs:30:5
+   |
+LL |     FIELD3
+   |     ^^^^^^ referenced constant has errors
+
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0080`.
diff --git a/src/test/ui/consts/issue-56164.rs b/src/test/ui/consts/issue-56164.rs
index 22ac75514f6..094ca377e03 100644
--- a/src/test/ui/consts/issue-56164.rs
+++ b/src/test/ui/consts/issue-56164.rs
@@ -1,5 +1,7 @@
 const fn foo() { (||{})() }
 //~^ ERROR cannot call non-const closure
+//~| ERROR erroneous constant used [const_err]
+//~| WARNING this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 
 const fn bad(input: fn()) {
     input()
diff --git a/src/test/ui/consts/issue-56164.stderr b/src/test/ui/consts/issue-56164.stderr
index 803424eedf3..b997aff0e83 100644
--- a/src/test/ui/consts/issue-56164.stderr
+++ b/src/test/ui/consts/issue-56164.stderr
@@ -8,11 +8,21 @@ LL | const fn foo() { (||{})() }
    = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
 
 error: function pointers are not allowed in const fn
-  --> $DIR/issue-56164.rs:5:5
+  --> $DIR/issue-56164.rs:7:5
    |
 LL |     input()
    |     ^^^^^^^
 
-error: aborting due to 2 previous errors
+error: erroneous constant used
+  --> $DIR/issue-56164.rs:1:18
+   |
+LL | const fn foo() { (||{})() }
+   |                  ^^^^^^ referenced constant has errors
+   |
+   = note: `#[deny(const_err)]` on by default
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0015`.
diff --git a/src/test/ui/consts/issue-66693.rs b/src/test/ui/consts/issue-66693.rs
index 909bef7aefb..99d28eb773f 100644
--- a/src/test/ui/consts/issue-66693.rs
+++ b/src/test/ui/consts/issue-66693.rs
@@ -8,7 +8,10 @@ static _FOO: () = panic!(true);
 //~^ ERROR: argument to `panic!()` in a const context must have type `&str`
 
 const fn _foo() {
-    panic!(&1); //~ ERROR: argument to `panic!()` in a const context must have type `&str`
+    panic!(&1);
+    //~^ ERROR: argument to `panic!()` in a const context must have type `&str`
+    //~| ERROR: erroneous constant used [const_err]
+    //~| WARNING: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
 }
 
 // ensure that conforming panics don't cause an error
diff --git a/src/test/ui/consts/issue-66693.stderr b/src/test/ui/consts/issue-66693.stderr
index 3530324bda2..b8257684983 100644
--- a/src/test/ui/consts/issue-66693.stderr
+++ b/src/test/ui/consts/issue-66693.stderr
@@ -22,5 +22,15 @@ LL |     panic!(&1);
    |
    = note: this error originates in the macro `$crate::panic::panic_2015` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 3 previous errors
+error: erroneous constant used
+  --> $DIR/issue-66693.rs:11:12
+   |
+LL |     panic!(&1);
+   |            ^^ referenced constant has errors
+   |
+   = note: `#[deny(const_err)]` on by default
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+
+error: aborting due to 4 previous errors
 
diff --git a/src/test/ui/consts/promotion.rs b/src/test/ui/consts/promotion.rs
index 580c6d62f10..e379e3aea13 100644
--- a/src/test/ui/consts/promotion.rs
+++ b/src/test/ui/consts/promotion.rs
@@ -4,11 +4,13 @@
 //[opt_with_overflow_checks]compile-flags: -C overflow-checks=on -O
 
 // build-pass
-#[allow(arithmetic_overflow)]
 
 const fn assert_static<T>(_: &'static T) {}
 
-const fn fail() -> i32 { 1/0 }
+#[allow(unconditional_panic)]
+const fn fail() -> i32 {
+    1/0
+}
 const C: i32 = {
     // Promoted that fails to evaluate in dead code -- this must work
     // (for backwards compatibility reasons).
diff --git a/src/test/ui/recursion/issue-26548-recursion-via-normalize.rs b/src/test/ui/recursion/issue-26548-recursion-via-normalize.rs
index 4fd5622b062..366ea7d3b3f 100644
--- a/src/test/ui/recursion/issue-26548-recursion-via-normalize.rs
+++ b/src/test/ui/recursion/issue-26548-recursion-via-normalize.rs
@@ -2,7 +2,6 @@
 //~| NOTE ...which requires computing layout of `core::option::Option<<S as Mirror>::It>`...
 //~| NOTE ...which requires computing layout of `core::option::Option<S>`...
 //~| NOTE ...which again requires computing layout of `S`, completing the cycle
-//~| NOTE cycle used when computing layout of `core::option::Option<S>`
 
 // build-fail
 
@@ -15,5 +14,6 @@ impl<T: ?Sized> Mirror for T {
 struct S(Option<<S as Mirror>::It>);
 
 fn main() {
+    //~^ NOTE cycle used when elaborating drops for `main`
     let _s = S(None);
 }
diff --git a/src/test/ui/recursion/issue-26548-recursion-via-normalize.stderr b/src/test/ui/recursion/issue-26548-recursion-via-normalize.stderr
index 6042379a918..5b675dc9f81 100644
--- a/src/test/ui/recursion/issue-26548-recursion-via-normalize.stderr
+++ b/src/test/ui/recursion/issue-26548-recursion-via-normalize.stderr
@@ -3,7 +3,11 @@ error[E0391]: cycle detected when computing layout of `S`
    = note: ...which requires computing layout of `core::option::Option<<S as Mirror>::It>`...
    = note: ...which requires computing layout of `core::option::Option<S>`...
    = note: ...which again requires computing layout of `S`, completing the cycle
-   = note: cycle used when computing layout of `core::option::Option<S>`
+note: cycle used when elaborating drops for `main`
+  --> $DIR/issue-26548-recursion-via-normalize.rs:16:1
+   |
+LL | fn main() {
+   | ^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/tools/clippy/tests/ui/crashes/ice-5497.stderr b/src/tools/clippy/tests/ui/crashes/ice-5497.stderr
new file mode 100644
index 00000000000..e75e7dc9136
--- /dev/null
+++ b/src/tools/clippy/tests/ui/crashes/ice-5497.stderr
@@ -0,0 +1,10 @@
+error: this operation will panic at runtime
+  --> $DIR/ice-5497.rs:9:22
+   |
+LL |     const OOB: i32 = [1][1] + T::OOB;
+   |                      ^^^^^^ index out of bounds: the length is 1 but the index is 1
+   |
+   = note: `#[deny(unconditional_panic)]` on by default
+
+error: aborting due to previous error
+