From 03e686892b395a7d5201bf5ae76d5d42f3dabd08 Mon Sep 17 00:00:00 2001
From: Tony Arcieri <bascule@gmail.com>
Date: Wed, 24 Apr 2024 10:12:28 -0600
Subject: [PATCH] CI: test build on actual `no_std` platforms (#67)

---
 .github/workflows/rustls-rustcrypto.yml | 37 +++++++++++++------------
 Cargo.lock                              |  1 +
 Cargo.toml                              |  4 +++
 3 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/.github/workflows/rustls-rustcrypto.yml b/.github/workflows/rustls-rustcrypto.yml
index e76faf0..826ca38 100644
--- a/.github/workflows/rustls-rustcrypto.yml
+++ b/.github/workflows/rustls-rustcrypto.yml
@@ -17,23 +17,6 @@ env:
   RUSTFLAGS: "-Dwarnings"
 
 jobs:
-  build:
-    strategy:
-      matrix:
-        toolchain:
-          - 1.75.0 # MSRV
-          - stable
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: RustCrypto/actions/cargo-cache@master
-      - uses: dtolnay/rust-toolchain@master
-        with:
-          toolchain: ${{ matrix.toolchain }}
-      - run: cargo build
-      - name: Test no_std with alloc build
-        run: cargo build --no-default-features --features tls12,alloc
-
   clippy:
     runs-on: ubuntu-latest
     steps:
@@ -63,10 +46,30 @@ jobs:
           components: rustfmt
       - run: cargo fmt --all -- --check
 
+  no_std:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - 1.75.0 # MSRV
+          - stable
+        target:
+          - armv7a-none-eabi
+          - thumbv7em-none-eabi
+          - wasm32-unknown-unknown
+    steps:
+      - uses: actions/checkout@v4
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{ matrix.rust }}
+          targets: ${{ matrix.target }}
+      - run: cargo build --no-default-features --features tls12,alloc --release --target ${{ matrix.target }}
+
   test:
     strategy:
       matrix:
         toolchain:
+          - 1.75.0 # MSRV
           - stable
     runs-on: ubuntu-latest
     steps:
diff --git a/Cargo.lock b/Cargo.lock
index 0255f28..bf81148 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -694,6 +694,7 @@ dependencies = [
  "digest",
  "ecdsa",
  "ed25519-dalek",
+ "getrandom",
  "hmac",
  "p256",
  "p384",
diff --git a/Cargo.toml b/Cargo.toml
index 985721c..c4f5481 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,6 +13,7 @@ categories = ["cryptography", "no-std"]
 keywords = ["rustls", "tls"]
 edition = "2021"
 rust-version = "1.75"
+resolver = "1" # Hack to enable the `custom` feature of `getrandom`
 
 # Ensure all dependencies + feats are mapped to crate features for correct usage
 # default features often have std breaking no_std and potentially other unwanted
@@ -40,6 +41,9 @@ signature = { version = "2.1.0", default-features = false }
 webpki = { package = "rustls-webpki", version = "0.102.0", default-features = false }
 x25519-dalek = { version = "2", default-features = false }
 
+[dev-dependencies]
+getrandom = { version = "0.2", features = ["custom"] } # workaround to build on no_std targets
+
 [features]
 default = ["std", "tls12", "zeroize"]
 logging = ["rustls/logging"]