Auto merge of #115696 - RalfJung:closure-ty-print, r=oli-obk

adjust how closure/generator types are printed

I saw `&[closure@$DIR/issue-20862.rs:2:5]` and I thought it is a slice type, because that's usually what `&[_]` is... it took me a while to realize that this is just a confusing printer and actually there's no slice. Let's use something that cannot be mistaken for a regular type.

23 files changed, 28 insertions, 28 deletions

diff --git a/src/tools/clippy/tests/ui/box_default.fixed b/src/tools/clippy/tests/ui/box_default.fixed
index 22c034c88ab..69cabcb32d3 100644
--- a/src/tools/clippy/tests/ui/box_default.fixed
+++ b/src/tools/clippy/tests/ui/box_default.fixed
@@ -36,7 +36,7 @@ fn main() {
     issue_10381();
 
     // `Box::<Option<_>>::default()` would be valid here, but not `Box::default()` or
-    // `Box::<Option<[closure@...]>::default()`
+    // `Box::<Option<{closure@...}>::default()`
     //
     // Would have a suggestion after https://github.com/rust-lang/rust/blob/fdd030127cc68afec44a8d3f6341525dd34e50ae/compiler/rustc_middle/src/ty/diagnostics.rs#L554-L563
     let mut unnameable = Box::new(Option::default());
diff --git a/src/tools/clippy/tests/ui/box_default.rs b/src/tools/clippy/tests/ui/box_default.rs
index 89e3888ba21..48fa8bc33bc 100644
--- a/src/tools/clippy/tests/ui/box_default.rs
+++ b/src/tools/clippy/tests/ui/box_default.rs
@@ -36,7 +36,7 @@ fn main() {
     issue_10381();
 
     // `Box::<Option<_>>::default()` would be valid here, but not `Box::default()` or
-    // `Box::<Option<[closure@...]>::default()`
+    // `Box::<Option<{closure@...}>::default()`
     //
     // Would have a suggestion after https://github.com/rust-lang/rust/blob/fdd030127cc68afec44a8d3f6341525dd34e50ae/compiler/rustc_middle/src/ty/diagnostics.rs#L554-L563
     let mut unnameable = Box::new(Option::default());
diff --git a/src/tools/clippy/tests/ui/crashes/ice-6251.stderr b/src/tools/clippy/tests/ui/crashes/ice-6251.stderr
index 68a5766c90c..11081dc8087 100644
--- a/src/tools/clippy/tests/ui/crashes/ice-6251.stderr
+++ b/src/tools/clippy/tests/ui/crashes/ice-6251.stderr
@@ -27,7 +27,7 @@ LL | fn bug<T>() -> impl Iterator<Item = [(); { |x: [u8]| x }]> {
    |                                            ^^^^^^^^^^^ expected `usize`, found closure
    |
    = note: expected type `usize`
-           found closure `[closure@$DIR/ice-6251.rs:4:44: 4:53]`
+           found closure `{closure@$DIR/ice-6251.rs:4:44: 4:53}`
 
 error: aborting due to 3 previous errors
 
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
index 0cba380ea1a..fcabb751db9 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.stack.stderr
@@ -24,7 +24,7 @@ note: inside closure
    |
 LL |             || drop(Box::from_raw(ptr)),
    |                     ^^^^^^^^^^^^^^^^^^
-note: inside `dealloc_while_running::<[closure@$DIR/newtype_pair_retagging.rs:LL:CC]>`
+note: inside `dealloc_while_running::<{closure@$DIR/newtype_pair_retagging.rs:LL:CC}>`
   --> $DIR/newtype_pair_retagging.rs:LL:CC
    |
 LL |     dealloc();
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
index f26fc6cbaae..19a05ec5dd3 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_pair_retagging.tree.stderr
@@ -35,7 +35,7 @@ note: inside closure
    |
 LL |             || drop(Box::from_raw(ptr)),
    |                ^^^^^^^^^^^^^^^^^^^^^^^^
-note: inside `dealloc_while_running::<[closure@$DIR/newtype_pair_retagging.rs:LL:CC]>`
+note: inside `dealloc_while_running::<{closure@$DIR/newtype_pair_retagging.rs:LL:CC}>`
   --> $DIR/newtype_pair_retagging.rs:LL:CC
    |
 LL |     dealloc();
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
index f76b6a57eac..6cbc6a86c09 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.stack.stderr
@@ -24,7 +24,7 @@ note: inside closure
    |
 LL |             || drop(Box::from_raw(ptr)),
    |                     ^^^^^^^^^^^^^^^^^^
-note: inside `dealloc_while_running::<[closure@$DIR/newtype_retagging.rs:LL:CC]>`
+note: inside `dealloc_while_running::<{closure@$DIR/newtype_retagging.rs:LL:CC}>`
   --> $DIR/newtype_retagging.rs:LL:CC
    |
 LL |     dealloc();
diff --git a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
index 687c72d574d..6364c51122a 100644
--- a/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
+++ b/src/tools/miri/tests/fail/both_borrows/newtype_retagging.tree.stderr
@@ -35,7 +35,7 @@ note: inside closure
    |
 LL |             || drop(Box::from_raw(ptr)),
    |                ^^^^^^^^^^^^^^^^^^^^^^^^
-note: inside `dealloc_while_running::<[closure@$DIR/newtype_retagging.rs:LL:CC]>`
+note: inside `dealloc_while_running::<{closure@$DIR/newtype_retagging.rs:LL:CC}>`
   --> $DIR/newtype_retagging.rs:LL:CC
    |
 LL |     dealloc();
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
index e4821bc0bac..4c477416416 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.both.stderr
@@ -14,7 +14,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_cannot_unwind` at RUSTLIB/core/src/panicking.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
index e4821bc0bac..4c477416416 100644
--- a/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
+++ b/src/tools/miri/tests/fail/function_calls/exported_symbol_bad_unwind2.definition.stderr
@@ -14,7 +14,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_cannot_unwind` at RUSTLIB/core/src/panicking.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/generator-pinned-moved.stderr b/src/tools/miri/tests/fail/generator-pinned-moved.stderr
index e29e352e64b..4cb8450c6d5 100644
--- a/src/tools/miri/tests/fail/generator-pinned-moved.stderr
+++ b/src/tools/miri/tests/fail/generator-pinned-moved.stderr
@@ -18,12 +18,12 @@ LL |     }; // *deallocate* generator_iterator
    |     ^
    = note: BACKTRACE (of the first span):
    = note: inside closure at $DIR/generator-pinned-moved.rs:LL:CC
-note: inside `<GeneratorIteratorAdapter<[static generator@$DIR/generator-pinned-moved.rs:LL:CC]> as std::iter::Iterator>::next`
+note: inside `<GeneratorIteratorAdapter<{static generator@$DIR/generator-pinned-moved.rs:LL:CC}> as std::iter::Iterator>::next`
   --> $DIR/generator-pinned-moved.rs:LL:CC
    |
 LL |         match me.resume(()) {
    |               ^^^^^^^^^^^^^
-   = note: inside `<std::boxed::Box<GeneratorIteratorAdapter<[static generator@$DIR/generator-pinned-moved.rs:LL:CC]>> as std::iter::Iterator>::next` at RUSTLIB/alloc/src/boxed.rs:LL:CC
+   = note: inside `<std::boxed::Box<GeneratorIteratorAdapter<{static generator@$DIR/generator-pinned-moved.rs:LL:CC}>> as std::iter::Iterator>::next` at RUSTLIB/alloc/src/boxed.rs:LL:CC
 note: inside `main`
   --> $DIR/generator-pinned-moved.rs:LL:CC
    |
diff --git a/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr b/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
index 70e10e8dc48..c63cfe06553 100644
--- a/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/uninit_uninhabited_type.stderr
@@ -11,7 +11,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
 note: inside `main`
diff --git a/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr b/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
index 56143b6c205..f954c4e9712 100644
--- a/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
+++ b/src/tools/miri/tests/fail/intrinsics/zero_fn_ptr.stderr
@@ -11,7 +11,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
 note: inside `main`
diff --git a/src/tools/miri/tests/fail/panic/bad_unwind.stderr b/src/tools/miri/tests/fail/panic/bad_unwind.stderr
index 18438c13b21..c2d007e5729 100644
--- a/src/tools/miri/tests/fail/panic/bad_unwind.stderr
+++ b/src/tools/miri/tests/fail/panic/bad_unwind.stderr
@@ -11,9 +11,9 @@ LL |     std::panic::catch_unwind(|| unwind()).unwrap_err();
    = help: see https://doc.rust-lang.org/nightly/reference/behavior-considered-undefined.html for further information
    = note: BACKTRACE:
    = note: inside closure at $DIR/bad_unwind.rs:LL:CC
-   = note: inside `std::panicking::r#try::do_call::<[closure@$DIR/bad_unwind.rs:LL:CC], ()>` at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::panicking::r#try::<(), [closure@$DIR/bad_unwind.rs:LL:CC]>` at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::panic::catch_unwind::<[closure@$DIR/bad_unwind.rs:LL:CC], ()>` at RUSTLIB/std/src/panic.rs:LL:CC
+   = note: inside `std::panicking::r#try::do_call::<{closure@$DIR/bad_unwind.rs:LL:CC}, ()>` at RUSTLIB/std/src/panicking.rs:LL:CC
+   = note: inside `std::panicking::r#try::<(), {closure@$DIR/bad_unwind.rs:LL:CC}>` at RUSTLIB/std/src/panicking.rs:LL:CC
+   = note: inside `std::panic::catch_unwind::<{closure@$DIR/bad_unwind.rs:LL:CC}, ()>` at RUSTLIB/std/src/panic.rs:LL:CC
 note: inside `main`
   --> $DIR/bad_unwind.rs:LL:CC
    |
diff --git a/src/tools/miri/tests/fail/panic/double_panic.stderr b/src/tools/miri/tests/fail/panic/double_panic.stderr
index a39522c8a61..5de7b3cf929 100644
--- a/src/tools/miri/tests/fail/panic/double_panic.stderr
+++ b/src/tools/miri/tests/fail/panic/double_panic.stderr
@@ -16,7 +16,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind_nobacktrace` at RUSTLIB/core/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_in_cleanup` at RUSTLIB/core/src/panicking.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort1.stderr b/src/tools/miri/tests/fail/panic/panic_abort1.stderr
index 404777344d7..6bd7157031a 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort1.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort1.stderr
@@ -12,7 +12,7 @@ LL |                 ABORT();
    = note: inside `std::panicking::rust_panic` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
 note: inside `main`
   --> $DIR/panic_abort1.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort2.stderr b/src/tools/miri/tests/fail/panic/panic_abort2.stderr
index 5512d145c6b..1d828d2e0f5 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort2.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort2.stderr
@@ -12,7 +12,7 @@ LL |                 ABORT();
    = note: inside `std::panicking::rust_panic` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
 note: inside `main`
   --> $DIR/panic_abort2.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort3.stderr b/src/tools/miri/tests/fail/panic/panic_abort3.stderr
index 9fdccd4e59e..5e43444572e 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort3.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort3.stderr
@@ -12,7 +12,7 @@ LL |                 ABORT();
    = note: inside `std::panicking::rust_panic` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
 note: inside `main`
   --> $DIR/panic_abort3.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/panic/panic_abort4.stderr b/src/tools/miri/tests/fail/panic/panic_abort4.stderr
index 3c9557ca4ab..12c4b857134 100644
--- a/src/tools/miri/tests/fail/panic/panic_abort4.stderr
+++ b/src/tools/miri/tests/fail/panic/panic_abort4.stderr
@@ -12,7 +12,7 @@ LL |                 ABORT();
    = note: inside `std::panicking::rust_panic` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
 note: inside `main`
   --> $DIR/panic_abort4.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr b/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
index 2385439c8a5..a1b9662961d 100644
--- a/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
+++ b/src/tools/miri/tests/fail/shims/fs/isolated_file.stderr
@@ -8,11 +8,11 @@ LL |         let fd = cvt_r(|| unsafe { open64(path.as_ptr(), flags, opts.mode a
    = help: or pass `-Zmiri-isolation-error=warn` to configure Miri to return an error code from isolated operations (if supported for that operation) and continue with a warning
    = note: BACKTRACE:
    = note: inside closure at RUSTLIB/std/src/sys/PLATFORM/fs.rs:LL:CC
-   = note: inside `std::sys::PLATFORM::cvt_r::<i32, [closure@std::sys::PLATFORM::fs::File::open_c::{closure#0}]>` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
+   = note: inside `std::sys::PLATFORM::cvt_r::<i32, {closure@std::sys::PLATFORM::fs::File::open_c::{closure#0}}>` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::sys::PLATFORM::fs::File::open_c` at RUSTLIB/std/src/sys/PLATFORM/fs.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/sys/PLATFORM/fs.rs:LL:CC
-   = note: inside `std::sys::PLATFORM::small_c_string::run_with_cstr::<std::sys::PLATFORM::fs::File, [closure@std::sys::PLATFORM::fs::File::open::{closure#0}]>` at RUSTLIB/std/src/sys/PLATFORM/small_c_string.rs:LL:CC
-   = note: inside `std::sys::PLATFORM::small_c_string::run_path_with_cstr::<std::sys::PLATFORM::fs::File, [closure@std::sys::PLATFORM::fs::File::open::{closure#0}]>` at RUSTLIB/std/src/sys/PLATFORM/small_c_string.rs:LL:CC
+   = note: inside `std::sys::PLATFORM::small_c_string::run_with_cstr::<std::sys::PLATFORM::fs::File, {closure@std::sys::PLATFORM::fs::File::open::{closure#0}}>` at RUSTLIB/std/src/sys/PLATFORM/small_c_string.rs:LL:CC
+   = note: inside `std::sys::PLATFORM::small_c_string::run_path_with_cstr::<std::sys::PLATFORM::fs::File, {closure@std::sys::PLATFORM::fs::File::open::{closure#0}}>` at RUSTLIB/std/src/sys/PLATFORM/small_c_string.rs:LL:CC
    = note: inside `std::sys::PLATFORM::fs::File::open` at RUSTLIB/std/src/sys/PLATFORM/fs.rs:LL:CC
    = note: inside `std::fs::OpenOptions::_open` at RUSTLIB/std/src/fs.rs:LL:CC
    = note: inside `std::fs::OpenOptions::open::<&std::path::Path>` at RUSTLIB/std/src/fs.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr b/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
index 8ebb35450e5..00ea6b27d4c 100644
--- a/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
+++ b/src/tools/miri/tests/fail/stacked_borrows/deallocate_against_protector1.stderr
@@ -17,7 +17,7 @@ note: inside closure
    |
 LL |         drop(unsafe { Box::from_raw(raw) });
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: inside `<[closure@$DIR/deallocate_against_protector1.rs:LL:CC] as std::ops::FnOnce<(&mut i32,)>>::call_once - shim` at RUSTLIB/core/src/ops/function.rs:LL:CC
+   = note: inside `<{closure@$DIR/deallocate_against_protector1.rs:LL:CC} as std::ops::FnOnce<(&mut i32,)>>::call_once - shim` at RUSTLIB/core/src/ops/function.rs:LL:CC
 note: inside `inner`
   --> $DIR/deallocate_against_protector1.rs:LL:CC
    |
diff --git a/src/tools/miri/tests/fail/terminate-terminator.stderr b/src/tools/miri/tests/fail/terminate-terminator.stderr
index e9277ebdbfd..dc634df831f 100644
--- a/src/tools/miri/tests/fail/terminate-terminator.stderr
+++ b/src/tools/miri/tests/fail/terminate-terminator.stderr
@@ -16,7 +16,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_cannot_unwind` at RUSTLIB/core/src/panicking.rs:LL:CC
diff --git a/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr b/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
index 55665e63e8a..fb2e77f9d2a 100644
--- a/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
+++ b/src/tools/miri/tests/fail/tree_borrows/strongly-protected.stderr
@@ -28,7 +28,7 @@ note: inside closure
    |
 LL |         drop(unsafe { Box::from_raw(raw) });
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: inside `<[closure@$DIR/strongly-protected.rs:LL:CC] as std::ops::FnOnce<(&mut i32,)>>::call_once - shim` at RUSTLIB/core/src/ops/function.rs:LL:CC
+   = note: inside `<{closure@$DIR/strongly-protected.rs:LL:CC} as std::ops::FnOnce<(&mut i32,)>>::call_once - shim` at RUSTLIB/core/src/ops/function.rs:LL:CC
 note: inside `inner`
   --> $DIR/strongly-protected.rs:LL:CC
    |
diff --git a/src/tools/miri/tests/fail/unwind-action-terminate.stderr b/src/tools/miri/tests/fail/unwind-action-terminate.stderr
index cf94dbb9909..7575300bc57 100644
--- a/src/tools/miri/tests/fail/unwind-action-terminate.stderr
+++ b/src/tools/miri/tests/fail/unwind-action-terminate.stderr
@@ -14,7 +14,7 @@ LL |     ABORT();
    = note: inside `std::sys::PLATFORM::abort_internal` at RUSTLIB/std/src/sys/PLATFORM/mod.rs:LL:CC
    = note: inside `std::panicking::rust_panic_with_hook` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<[closure@std::panicking::begin_panic_handler::{closure#0}], !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
+   = note: inside `std::sys_common::backtrace::__rust_end_short_backtrace::<{closure@std::panicking::begin_panic_handler::{closure#0}}, !>` at RUSTLIB/std/src/sys_common/backtrace.rs:LL:CC
    = note: inside `std::panicking::begin_panic_handler` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_nounwind` at RUSTLIB/core/src/panicking.rs:LL:CC
    = note: inside `core::panicking::panic_cannot_unwind` at RUSTLIB/core/src/panicking.rs:LL:CC