diff --git a/hal-x86_64/Cargo.toml b/hal-x86_64/Cargo.toml
index a5489ef9a..ea66edc22 100644
--- a/hal-x86_64/Cargo.toml
+++ b/hal-x86_64/Cargo.toml
@@ -6,7 +6,9 @@ edition = "2018"
 license = "MIT"
 
 [features]
+default = ["alloc"]
 log = ["tracing/log"]
+alloc = []
 
 [dependencies]
 acpi = "4.1.1"
diff --git a/hal-x86_64/src/cpu.rs b/hal-x86_64/src/cpu.rs
index b18b5eb80..6100c8806 100644
--- a/hal-x86_64/src/cpu.rs
+++ b/hal-x86_64/src/cpu.rs
@@ -3,6 +3,7 @@ use mycelium_util::bits;
 
 pub mod entropy;
 pub mod intrinsics;
+#[cfg(feature = "alloc")]
 pub mod local;
 mod msr;
 pub use self::msr::Msr;
diff --git a/hal-x86_64/src/lib.rs b/hal-x86_64/src/lib.rs
index 773fc0129..011f4f9d7 100644
--- a/hal-x86_64/src/lib.rs
+++ b/hal-x86_64/src/lib.rs
@@ -3,18 +3,17 @@
 // Allow const operands in asm.
 #![feature(asm_const)]
 #![feature(abi_x86_interrupt)]
-#![feature(doc_cfg)]
+#![feature(doc_cfg, doc_auto_cfg)]
+#![feature(extern_types)]
 // A bunch of const fn features.
 #![feature(const_mut_refs)]
 // Oftentimes it's necessary to write to a value at a particular location in
 // memory, and these types don't implement Copy to ensure they aren't
 // inadvertantly copied.
 #![allow(clippy::trivially_copy_pass_by_ref)]
-// Macros generated by `tracing` often generate large amounts of code, which
-// causes this lint to complain about relatively simple methods.
-#![allow(clippy::cognitive_complexity)]
 
 pub(crate) use hal_core::{PAddr, VAddr};
+#[cfg(feature = "alloc")]
 extern crate alloc;
 
 pub mod control_regs;