tests: conditionally enable feature(lint_reasons)

Required for CI on Rust 1.78.

Signed-off-by: Benno Lossin <benno.lossin@proton.me>

Author: BennoLossin

tests/alloc_fail.rs

@@ -1,4 +1,5 @@
 #![cfg_attr(feature = "alloc", feature(allocator_api))]
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
 
 #[cfg(all(
     feature = "alloc",

tests/const-generic-default.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
+
 use pin_init::*;
 
 #[pin_data]

tests/many_generics.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
+
 use core::{marker::PhantomPinned, pin::Pin};
 use pin_init::*;
 

tests/ring_buf.rs

@@ -1,4 +1,5 @@
 #![allow(clippy::undocumented_unsafe_blocks)]
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
 #![cfg_attr(feature = "alloc", feature(allocator_api))]
 
 use core::{

tests/ui.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
+
 #[cfg(not(any(miri, NO_UI_TESTS)))]
 #[test]
 fn compile_fail() {

tests/ui/expand/many_generics.expanded.rs

@@ -1,3 +1,4 @@
+#![feature(lint_reasons)]
 use core::{marker::PhantomPinned, pin::Pin};
 use pin_init::*;
 trait Bar<'a, const ID: usize = 0> {

tests/zeroing.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(not(RUSTC_LINT_REASONS_IS_STABLE), feature(lint_reasons))]
+
 use std::{marker::PhantomPinned, ptr::addr_of_mut};
 
 use pin_init::*;