From 8a2deddac7179f6ef98957881517c518e2fa2731 Mon Sep 17 00:00:00 2001
From: Tamir Duberstein <tamird@gmail.com>
Date: Sat, 24 May 2025 14:32:15 -0400
Subject: [PATCH] aya-ebpf: add a dedicated generic_const_exprs cfg
---
ebpf/aya-ebpf/build.rs | 3 ++-
ebpf/aya-ebpf/src/lib.rs | 7 ++++++-
ebpf/aya-ebpf/src/maps/ring_buf.rs | 8 ++++----
3 files changed, 12 insertions(+), 6 deletions(-)
diff --git a/ebpf/aya-ebpf/build.rs b/ebpf/aya-ebpf/build.rs
index c4dd61e6..7b0557b2 100644
--- a/ebpf/aya-ebpf/build.rs
+++ b/ebpf/aya-ebpf/build.rs
@@ -28,11 +28,12 @@ fn main() {
}
println!("))");
- println!("cargo::rustc-check-cfg=cfg(unstable)");
+ println!("cargo::rustc-check-cfg=cfg(generic_const_exprs,unstable)");
}
#[rustversion::nightly]
fn check_rust_version() {
+ println!("cargo:rustc-cfg=generic_const_exprs");
println!("cargo:rustc-cfg=unstable");
}
diff --git a/ebpf/aya-ebpf/src/lib.rs b/ebpf/aya-ebpf/src/lib.rs
index 971a3c40..d842abaf 100644
--- a/ebpf/aya-ebpf/src/lib.rs
+++ b/ebpf/aya-ebpf/src/lib.rs
@@ -8,7 +8,12 @@
html_logo_url = "https://aya-rs.dev/assets/images/crabby.svg",
html_favicon_url = "https://aya-rs.dev/assets/images/crabby.svg"
)]
-#![cfg_attr(unstable, expect(incomplete_features), feature(generic_const_exprs))]
+// TODO(https://github.com/rust-lang/rust/issues/141492): reenable this.
+#![cfg_attr(
+ generic_const_exprs,
+ expect(incomplete_features),
+ feature(generic_const_exprs)
+)]
#![cfg_attr(unstable, feature(never_type))]
#![cfg_attr(target_arch = "bpf", feature(asm_experimental_arch))]
#![warn(clippy::cast_lossless, clippy::cast_sign_loss)]
diff --git a/ebpf/aya-ebpf/src/maps/ring_buf.rs b/ebpf/aya-ebpf/src/maps/ring_buf.rs
index e7db9a53..9de0a7fe 100644
--- a/ebpf/aya-ebpf/src/maps/ring_buf.rs
+++ b/ebpf/aya-ebpf/src/maps/ring_buf.rs
@@ -14,7 +14,7 @@ use crate::{
maps::PinningType,
};
-#[cfg(unstable)]
+#[cfg(generic_const_exprs)]
mod const_assert {
pub struct Assert<const COND: bool> {}
@@ -22,7 +22,7 @@ mod const_assert {
impl IsTrue for Assert<true> {}
}
-#[cfg(unstable)]
+#[cfg(generic_const_exprs)]
use const_assert::{Assert, IsTrue};
#[repr(transparent)]
@@ -101,7 +101,7 @@ impl RingBuf {
/// Reserve memory in the ring buffer that can fit `T`.
///
/// Returns `None` if the ring buffer is full.
- #[cfg(unstable)]
+ #[cfg(generic_const_exprs)]
pub fn reserve<T: 'static>(&self, flags: u64) -> Option<RingBufEntry<T>>
where
Assert<{ 8 % mem::align_of::<T>() == 0 }>: IsTrue,
@@ -117,7 +117,7 @@ impl RingBuf {
/// be equal or smaller than 8. If you use this with a `T` that isn't properly aligned, this
/// function will be compiled to a panic; depending on your panic_handler, this may make
/// the eBPF program fail to load, or it may make it have undefined behavior.
- #[cfg(not(unstable))]
+ #[cfg(not(generic_const_exprs))]
pub fn reserve<T: 'static>(&self, flags: u64) -> Option<RingBufEntry<T>> {
assert_eq!(8 % mem::align_of::<T>(), 0);
self.reserve_impl(flags)