Const generics port

.github/workflows/build.yml

@@ -105,7 +105,7 @@ jobs:
         toolchain:
           - stable
           - nightly
-          - 1.36.0
+          - 1.51.0
         features:
           - serde
         buildtype:
@@ -242,7 +242,7 @@ jobs:
       - name: Install Rust
         uses: actions-rs/toolchain@v1
         with:
-          toolchain: 1.36.0
+          toolchain: 1.51.0
           target: x86_64-unknown-linux-gnu
           override: true
 

CHANGELOG.md

@@ -7,6 +7,19 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
+### Changed
+
+- [breaking-change] Converted all data structures to use the `const generics` MVP
+- [breaking-change] `HistoryBuffer` is now working with const constructors and non-`Copy` data
+- [breaking-change] `HistoryBuffer::as_slice` and others now only return initialized values
+- [breaking-change] `MultiCore`/`SingleCore` is now removed from `spsc::Queue`
+- [breaking-change] `spsc::Queue` is now `usize` only
+- [breaking-change] `spsc::Queue` now sacrifices one element for correctness (see issue #207), i.e. it creates an `N - 1` sized queue instead of the old that generated an size `N` queue
+- `Pool` and `MPMC` now works on `thumbv6m`
+- [breaking-change] `String` has had `utf8` related methods removed as this can be done via `str`
+- [breaking-change] No data structures implement `AsSlice` traits any more, now using `AsRef` and `AsMut`
+- `IndexMap::new()` is now a `const-fn`
+
 ## [v0.6.1] - 2021-03-02
 
 ### Fixed

Cargo.toml

@@ -2,6 +2,7 @@
 authors = [
   "Jorge Aparicio <[email protected]>",
   "Per Lindgren <[email protected]>",
+  "Emil Fresk <[email protected]>",
 ]
 categories = [
     "data-structures",
@@ -31,10 +32,11 @@ __trybuild = []
 [target.x86_64-unknown-linux-gnu.dev-dependencies]
 scoped_threadpool = "0.1.8"
 
+[target.thumbv6m-none-eabi.dependencies]
+atomic-polyfill = "0.1.2"
+
 [dependencies]
-as-slice = "0.1.5"
-generic-array = "0.14.4"
-hash32 = "0.1.0"
+hash32 = "0.2.1"
 
 [dependencies.serde]
 version = "1"

build.rs

@@ -24,10 +24,7 @@ fn main() -> Result<(), Box<dyn Error>> {
     // built-in targets with no atomic / CAS support as of nightly-2019-12-17
     // see the `no-atomics.sh` / `no-cas.sh` script sitting next to this file
     match &target[..] {
-        "thumbv6m-none-eabi"
-        | "msp430-none-elf"
-        | "riscv32i-unknown-none-elf"
-        | "riscv32imc-unknown-none-elf" => {}
+        "msp430-none-elf" | "riscv32i-unknown-none-elf" | "riscv32imc-unknown-none-elf" => {}
 
         _ => {
             println!("cargo:rustc-cfg=has_cas");

cfail/ui/freeze.rs

@@ -1,7 +1,7 @@
-use heapless::{consts, spsc::Queue};
+use heapless::spsc::Queue;
 
 fn main() {
-    let mut q: Queue<u8, consts::U4> = Queue::new();
+    let mut q: Queue<u8, 4> = Queue::new();
 
     let (_p, mut _c) = q.split();
     q.enqueue(0).unwrap();

cfail/ui/not-send.rs

@@ -3,8 +3,8 @@
 use core::marker::PhantomData;
 
 use heapless::{
-    consts,
     spsc::{Consumer, Producer, Queue},
+    HistoryBuffer, Vec,
 };
 
 type NotSend = PhantomData<*const ()>;
@@ -16,8 +16,9 @@ where
 }
 
 fn main() {
-    is_send::<Consumer<NotSend, consts::U4>>();
-    is_send::<Producer<NotSend, consts::U4>>();
-    is_send::<Queue<NotSend, consts::U4>>();
-    is_send::<heapless::Vec<NotSend, consts::U4>>();
+    is_send::<Consumer<NotSend, 4>>();
+    is_send::<Producer<NotSend, 4>>();
+    is_send::<Queue<NotSend, 4>>();
+    is_send::<Vec<NotSend, 4>>();
+    is_send::<HistoryBuffer<NotSend, 4>>();
 }

cfail/ui/not-send.stderr

@@ -1,83 +1,89 @@
 error[E0277]: `*const ()` cannot be sent between threads safely
   --> $DIR/not-send.rs:19:5
    |
-19 |     is_send::<Consumer<NotSend, consts::U4>>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
+12 | fn is_send<T>()
+   |    ------- required by a bound in this
+13 | where
+14 |     T: Send,
+   |        ---- required by this bound in `is_send`
+...
+19 |     is_send::<Consumer<NotSend, 4>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
    |
-   = help: within `std::marker::PhantomData<*const ()>`, the trait `std::marker::Send` is not implemented for `*const ()`
-   = note: required because it appears within the type `std::marker::PhantomData<*const ()>`
-   = note: required because of the requirements on the impl of `std::marker::Send` for `heapless::spsc::split::Consumer<'_, std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-note: required by `is_send`
-  --> $DIR/not-send.rs:12:1
-   |
-12 | / fn is_send<T>()
-13 | | where
-14 | |     T: Send,
-15 | | {
-16 | | }
-   | |_^
+   = help: within `PhantomData<*const ()>`, the trait `Send` is not implemented for `*const ()`
+   = note: required because it appears within the type `PhantomData<*const ()>`
+   = note: required because of the requirements on the impl of `Send` for `Consumer<'_, PhantomData<*const ()>, 4_usize>`
 
 error[E0277]: `*const ()` cannot be sent between threads safely
   --> $DIR/not-send.rs:20:5
    |
-20 |     is_send::<Producer<NotSend, consts::U4>>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
-   |
-   = help: within `std::marker::PhantomData<*const ()>`, the trait `std::marker::Send` is not implemented for `*const ()`
-   = note: required because it appears within the type `std::marker::PhantomData<*const ()>`
-   = note: required because of the requirements on the impl of `std::marker::Send` for `heapless::spsc::split::Producer<'_, std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-note: required by `is_send`
-  --> $DIR/not-send.rs:12:1
+12 | fn is_send<T>()
+   |    ------- required by a bound in this
+13 | where
+14 |     T: Send,
+   |        ---- required by this bound in `is_send`
+...
+20 |     is_send::<Producer<NotSend, 4>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
    |
-12 | / fn is_send<T>()
-13 | | where
-14 | |     T: Send,
-15 | | {
-16 | | }
-   | |_^
+   = help: within `PhantomData<*const ()>`, the trait `Send` is not implemented for `*const ()`
+   = note: required because it appears within the type `PhantomData<*const ()>`
+   = note: required because of the requirements on the impl of `Send` for `Producer<'_, PhantomData<*const ()>, 4_usize>`
 
 error[E0277]: `*const ()` cannot be sent between threads safely
   --> $DIR/not-send.rs:21:5
    |
-21 |     is_send::<Queue<NotSend, consts::U4>>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
-   |
-   = help: within `std::marker::PhantomData<*const ()>`, the trait `std::marker::Send` is not implemented for `*const ()`
-   = note: required because it appears within the type `std::marker::PhantomData<*const ()>`
-   = note: required because of the requirements on the impl of `std::marker::Send` for `generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-   = note: required because it appears within the type `std::mem::ManuallyDrop<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `std::mem::MaybeUninit<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `heapless::i::Queue<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `heapless::spsc::Queue<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-note: required by `is_send`
-  --> $DIR/not-send.rs:12:1
+12 | fn is_send<T>()
+   |    ------- required by a bound in this
+13 | where
+14 |     T: Send,
+   |        ---- required by this bound in `is_send`
+...
+21 |     is_send::<Queue<NotSend, 4>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
    |
-12 | / fn is_send<T>()
-13 | | where
-14 | |     T: Send,
-15 | | {
-16 | | }
-   | |_^
+   = help: within `Queue<PhantomData<*const ()>, 4_usize>`, the trait `Send` is not implemented for `*const ()`
+   = note: required because it appears within the type `PhantomData<*const ()>`
+   = note: required because it appears within the type `ManuallyDrop<PhantomData<*const ()>>`
+   = note: required because it appears within the type `MaybeUninit<PhantomData<*const ()>>`
+   = note: required because it appears within the type `UnsafeCell<MaybeUninit<PhantomData<*const ()>>>`
+   = note: required because it appears within the type `[UnsafeCell<MaybeUninit<PhantomData<*const ()>>>; 4]`
+   = note: required because it appears within the type `Queue<PhantomData<*const ()>, 4_usize>`
 
 error[E0277]: `*const ()` cannot be sent between threads safely
   --> $DIR/not-send.rs:22:5
    |
-22 |     is_send::<heapless::Vec<NotSend, consts::U4>>();
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
+12 | fn is_send<T>()
+   |    ------- required by a bound in this
+13 | where
+14 |     T: Send,
+   |        ---- required by this bound in `is_send`
+...
+22 |     is_send::<Vec<NotSend, 4>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
+   |
+   = help: within `heapless::Vec<PhantomData<*const ()>, 4_usize>`, the trait `Send` is not implemented for `*const ()`
+   = note: required because it appears within the type `PhantomData<*const ()>`
+   = note: required because it appears within the type `[PhantomData<*const ()>; 4]`
+   = note: required because it appears within the type `ManuallyDrop<[PhantomData<*const ()>; 4]>`
+   = note: required because it appears within the type `MaybeUninit<[PhantomData<*const ()>; 4]>`
+   = note: required because it appears within the type `heapless::Vec<PhantomData<*const ()>, 4_usize>`
+
+error[E0277]: `*const ()` cannot be sent between threads safely
+  --> $DIR/not-send.rs:23:5
    |
-   = help: within `std::marker::PhantomData<*const ()>`, the trait `std::marker::Send` is not implemented for `*const ()`
-   = note: required because it appears within the type `std::marker::PhantomData<*const ()>`
-   = note: required because of the requirements on the impl of `std::marker::Send` for `generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-   = note: required because it appears within the type `std::mem::ManuallyDrop<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `std::mem::MaybeUninit<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `heapless::i::Vec<generic_array::GenericArray<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>>`
-   = note: required because it appears within the type `heapless::vec::Vec<std::marker::PhantomData<*const ()>, typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UInt<typenum::uint::UTerm, typenum::bit::B1>, typenum::bit::B0>, typenum::bit::B0>>`
-note: required by `is_send`
-  --> $DIR/not-send.rs:12:1
+12 | fn is_send<T>()
+   |    ------- required by a bound in this
+13 | where
+14 |     T: Send,
+   |        ---- required by this bound in `is_send`
+...
+23 |     is_send::<HistoryBuffer<NotSend, 4>>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ `*const ()` cannot be sent between threads safely
    |
-12 | / fn is_send<T>()
-13 | | where
-14 | |     T: Send,
-15 | | {
-16 | | }
-   | |_^
+   = help: within `HistoryBuffer<PhantomData<*const ()>, 4_usize>`, the trait `Send` is not implemented for `*const ()`
+   = note: required because it appears within the type `PhantomData<*const ()>`
+   = note: required because it appears within the type `ManuallyDrop<PhantomData<*const ()>>`
+   = note: required because it appears within the type `MaybeUninit<PhantomData<*const ()>>`
+   = note: required because it appears within the type `[MaybeUninit<PhantomData<*const ()>>; 4]`
+   = note: required because it appears within the type `HistoryBuffer<PhantomData<*const ()>, 4_usize>`