Fix clippy tests

Author: goldsteinn

library/core/src/panic.rs

@@ -131,9 +131,9 @@ pub macro unreachable_2015 {
     // cold function. This moves the codegen for setting up the
     // arguments to the panic implementation function to the
     // presumably cold panic path.
-    () => ({
-        $crate::panicking::unreachable_cold_explicit();
-    }),
+    () => (
+        $crate::panicking::unreachable_cold_explicit()
+    ),
     ($msg:literal $(,)?) => ({
         #[cold]
         #[track_caller]
@@ -165,9 +165,9 @@ pub macro unreachable_2015 {
 )]
 #[rustc_macro_transparency = "semitransparent"]
 pub macro unreachable_2021 {
-    () => ({
-        $crate::panicking::unreachable_cold_explicit();
-    }),
+    () => (
+        $crate::panicking::unreachable_cold_explicit()
+    ),
     // Special-case the single-argument case for const_panic.
     ("{}", $arg:expr $(,)?) => ({
         #[cold]

library/core/src/panicking.rs

@@ -261,13 +261,15 @@ pub const fn panic_str_2015(expr: &str) -> ! {
 #[cold]
 #[track_caller]
 #[inline(never)]
+#[rustc_const_unstable(feature = "panic_internals", issue = "none")]
 pub const fn panic_cold_explicit() -> ! {
     panic("explicit panic");
 }
 
 #[cold]
 #[track_caller]
 #[inline(never)]
+#[rustc_const_unstable(feature = "panic_internals", issue = "none")]
 pub const fn unreachable_cold_explicit() -> ! {
     panic("internal error: entered unreachable code");
 }

src/tools/clippy/tests/ui/missing_const_for_thread_local.stderr

@@ -37,13 +37,5 @@ error: initializer for `thread_local` value can be made `const`
 LL |         static PEEL_ME_MANY: i32 = { let x = 1; x * x };
    |                                    ^^^^^^^^^^^^^^^^^^^^ help: replace with: `const { { let x = 1; x * x } }`
 
-error: initializer for `thread_local` value can be made `const`
-  --> tests/ui/missing_const_for_thread_local.rs:64:55
-   |
-LL |         static STATE_12637_UNREACHABLE: Cell<usize> = unreachable!();
-   |                                                       ^^^^^^^^^^^^^^
-   |
-   = note: this error originates in the macro `$crate::panic::unreachable_2021` which comes from the expansion of the macro `unreachable` (in Nightly builds, run with -Z macro-backtrace for more info)
-
-error: aborting due to 7 previous errors
+error: aborting due to 6 previous errors