support nightly-2017-09-22

Author: japaric

cortex-m-rt/CHANGELOG.md

@@ -7,7 +7,16 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 
-## [v0.3.10] - 2018-01-17
+## [v0.3.11] - 2018-01-17
+
+### Changed
+
+- Dynamically support recent nightlies, which have the `termination` lang item, and
+  nightly-2017-09-22, which doesn't. That nightly version is used by the docs.rs builder. Supporting
+  that version instead of rejecting it ensures this crate and its reverse-dependencies will get
+  their documentation built by the docs.rs service.
+
+## [v0.3.10] - 2018-01-17 - YANKED
 
 ### Removed
 
@@ -203,7 +212,8 @@ section                size        addr
 
 Initial release
 
-[Unreleased]: https://github.com/japaric/cortex-m-rt/compare/v0.3.10...HEAD
+[Unreleased]: https://github.com/japaric/cortex-m-rt/compare/v0.3.11...HEAD
+[v0.3.11]: https://github.com/japaric/cortex-m-rt/compare/v0.3.10...v0.3.11
 [v0.3.10]: https://github.com/japaric/cortex-m-rt/compare/v0.3.9...v0.3.10
 [v0.3.9]: https://github.com/japaric/cortex-m-rt/compare/v0.3.8...v0.3.9
 [v0.3.8]: https://github.com/japaric/cortex-m-rt/compare/v0.3.7...v0.3.8

cortex-m-rt/Cargo.toml

@@ -7,7 +7,7 @@ keywords = ["arm", "cortex-m", "runtime", "startup"]
 license = "MIT OR Apache-2.0"
 name = "cortex-m-rt"
 repository = "https://github.com/japaric/cortex-m-rt"
-version = "0.3.10"
+version = "0.3.11"
 
 [dependencies]
 cortex-m = "0.3.0"
@@ -19,3 +19,4 @@ abort-on-panic = []
 
 [build-dependencies]
 rustc_version = "0.2.1"
+chrono = "0.4.0"

cortex-m-rt/build.rs

@@ -1,11 +1,25 @@
+extern crate chrono;
 extern crate rustc_version;
 
 use std::env;
 use std::fs::File;
 use std::io::Write;
 use std::path::PathBuf;
 
+use chrono::NaiveDate;
+
 fn main() {
+    let date: NaiveDate = rustc_version::version_meta()
+        .unwrap()
+        .commit_date
+        .unwrap()
+        .parse()
+        .unwrap();
+
+    if date > NaiveDate::from_ymd(2017, 12, 26) {
+        println!("cargo:rustc-cfg=has_termination_lang")
+    }
+
     let target = env::var("TARGET").unwrap();
 
     has_fpu(&target);

cortex-m-rt/src/lang_items.rs

@@ -5,7 +5,8 @@ unsafe extern "C" fn panic_fmt(_: ::core::fmt::Arguments, _: &'static str, _: u3
     ::core::intrinsics::abort()
 }
 
-/// Lang item required to make the normal `main` work in applications
+// Lang item required to make the normal `main` work in applications
+//
 // This is how the `start` lang item works:
 // When `rustc` compiles a binary crate, it creates a `main` function that looks
 // like this:
@@ -23,6 +24,7 @@ unsafe extern "C" fn panic_fmt(_: ::core::fmt::Arguments, _: &'static str, _: u3
 // The final piece is that the entry point of our program, the reset handler,
 // has to call `rustc_main`. That's covered by the `reset_handler` function in
 // root of this crate.
+#[cfg(has_termination_trait)]
 #[lang = "start"]
 extern "C" fn start<T>(main: fn() -> T, _argc: isize, _argv: *const *const u8) -> isize
 where
@@ -33,11 +35,21 @@ where
     0
 }
 
+#[cfg(not(has_termination_trait))]
+#[lang = "start"]
+extern "C" fn start(main: fn(), _argc: isize, _argv: *const *const u8) -> isize {
+    main();
+
+    0
+}
+
 #[lang = "termination"]
+#[cfg(has_termination_trait)]
 pub trait Termination {
     fn report(self) -> i32;
 }
 
+#[cfg(has_termination_trait)]
 impl Termination for () {
     fn report(self) -> i32 {
         0

cortex-m-rt/src/lib.rs

@@ -284,7 +284,9 @@
 #![no_std]
 
 extern crate compiler_builtins;
+#[cfg(target_arch = "arm")]
 extern crate cortex_m;
+#[cfg(target_arch = "arm")]
 extern crate r0;
 
 #[cfg(not(test))]