Fix warnings + always build as no_std

Cargo.toml

@@ -22,9 +22,9 @@ bitflags = "2"
 serde = { version = "1.0", features = ["derive"], optional = true }
 
 [features]
-default = ["std", "full-decoder", "formatter"]
+default = ["full-decoder", "formatter"]
 alloc = []
-std = ["alloc"]
+std = ["alloc"] # currently alias for "alloc", but may change in the future
 full-decoder = []
 formatter = ["alloc", "full-decoder"]
 encoder = ["alloc", "full-decoder"]

src/decoder.rs

@@ -1,5 +1,7 @@
 use crate::*;
-use core::{fmt, hash, marker::PhantomData, mem, mem::MaybeUninit, ops, ptr};
+use core::{fmt, marker::PhantomData, mem::MaybeUninit, ops};
+#[cfg(feature = "full-decoder")]
+use core::{hash,mem, ptr};
 
 /// Decodes raw instruction bytes into a machine-readable struct.
 #[derive(Clone, Debug)]

src/lib.rs

@@ -1,6 +1,6 @@
+#![no_std]
 // The doc-test in README.md needs formatter
 #![cfg_attr(feature = "formatter", doc = include_str!("../README.md"))]
-#![cfg_attr(not(feature = "std"), no_std)]
 
 //! ## Navigation
 //!