Fix no-std build and bump MSRV to 1.61

Signed-off-by: John Nunley <dev@notgull.net>

.github/workflows/ci.yml

@@ -58,6 +58,11 @@ jobs:
 
   msrv:
     runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        # When updating this, the reminder to update the minimum supported
+        # Rust version in Cargo.toml.
+        rust: ['1.61']
     steps:
       - uses: actions/checkout@v4
       - name: Install cargo-hack

Cargo.toml

@@ -5,8 +5,8 @@ name = "async-lock"
 # - Create "v3.x.y" git tag
 version = "3.3.0"
 authors = ["Stjepan Glavina <stjepang@gmail.com>"]
-edition = "2021"
-rust-version = "1.60"
+edition = "2018"
+rust-version = "1.61"
 description = "Async synchronization primitives"
 license = "Apache-2.0 OR MIT"
 repository = "https://github.com/smol-rs/async-lock"

src/lib.rs

@@ -58,6 +58,7 @@ macro_rules! ready {
 /// Pins a variable on the stack.
 ///
 /// TODO: Drop in favor of `core::pin::pin`, once MSRV is bumped to 1.68.
+#[cfg(all(feature = "std", not(target_family = "wasm")))]
 macro_rules! pin {
     ($($x:ident),* $(,)?) => {
         $(

src/once_cell.rs

@@ -9,9 +9,12 @@ use core::sync::atomic::{AtomicUsize, Ordering};
 #[cfg(all(feature = "std", not(target_family = "wasm")))]
 use core::task::{Context, Poll, RawWaker, RawWakerVTable, Waker};
 
-use event_listener::{Event, Listener};
+use event_listener::Event;
 use event_listener_strategy::{NonBlocking, Strategy};
 
+#[cfg(all(feature = "std", not(target_family = "wasm")))]
+use event_listener::Listener;
+
 /// The current state of the `OnceCell`.
 #[derive(Copy, Clone, PartialEq, Eq)]
 #[repr(usize)]