Made compatible with thumbv6m-none-eabi

Cargo.toml

@@ -45,6 +45,9 @@ matrixmultiply = { version = "0.3.2", default-features = false, features=["cgemm
 serde = { version = "1.0", optional = true, default-features = false, features = ["alloc"] }
 rawpointer = { version = "0.2" }
 
+portable-atomic = { git = "https://github.com/taiki-e/portable-atomic.git", rev = "4e66bd3", optional = true }
+portable-atomic-util = { git = "https://github.com/taiki-e/portable-atomic.git", rev = "4e66bd3", features = ["alloc"], optional = true}
+
 [dev-dependencies]
 defmac = "0.2"
 quickcheck = { version = "1.0", default-features = false }
@@ -70,6 +73,9 @@ docs = ["approx", "serde", "rayon"]
 std = ["num-traits/std", "matrixmultiply/std"]
 rayon = ["rayon_", "std"]
 
+portable-atomic = ["dep:portable-atomic", "dep:portable-atomic-util"]
+critical-section = ["portable-atomic/critical-section"]
+
 matrixmultiply-threading = ["matrixmultiply/threading"]
 
 [profile.bench]

README.rst

@@ -97,6 +97,14 @@ your `Cargo.toml`.
 
   - Enable the ``threading`` feature in the matrixmultiply package
 
+- ``portable-atomic``
+
+  - Enables ``portable_atomic`` package for compatability with microcontrollers
+
+- ``critical-section``
+
+  - Whether ``portable_atomic`` should use ``critical-section``
+
 How to use with cargo
 ---------------------
 

src/data_traits.rs

@@ -10,7 +10,12 @@
 
 use rawpointer::PointerExt;
 
+#[cfg(not(feature = "portable-atomic"))]
 use alloc::sync::Arc;
+
+#[cfg(feature = "portable-atomic")]
+use portable_atomic_util::Arc;
+
 #[cfg(not(feature = "std"))]
 use alloc::vec::Vec;
 use std::mem::MaybeUninit;

src/lib.rs

@@ -124,7 +124,12 @@ extern crate cblas_sys;
 #[cfg(feature = "docs")]
 pub mod doc;
 
+#[cfg(not(feature = "portable-atomic"))]
 use alloc::sync::Arc;
+
+#[cfg(feature = "portable-atomic")]
+use portable_atomic_util::Arc;
+
 use std::marker::PhantomData;
 
 pub use crate::dimension::dim::*;