CI: test build on actual no_std platforms

.github/workflows/rustls-rustcrypto.yml

@@ -17,22 +17,6 @@ env:
   RUSTFLAGS: "-Dwarnings"
 
 jobs:
-  build:
-    strategy:
-      matrix:
-        toolchain:
-          - 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:
@@ -43,7 +27,6 @@ jobs:
           components: clippy
       - run: cargo clippy --all --all-features -- -D warnings
 
-
   doc:
     runs-on: ubuntu-latest
     steps:
@@ -63,6 +46,25 @@ jobs:
           components: rustfmt
       - run: cargo fmt --all -- --check
 
+  no_std:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        rust:
+          - 1.56.0 # 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:

Cargo.toml

@@ -21,7 +21,7 @@ p384 = { version = "0.13.0", default-features = false, features = ["pem", "ecdsa
 paste = { version = "1.0.14", default-features = false }
 pkcs8 = { version = "0.10.2", default-features = false, features = ["pem", "pkcs5"] }
 pki-types = { package = "rustls-pki-types", version = "1.0.1", default-features = false }
-rand_core = { version = "0.6.4", default-features = false, features = ["getrandom"] }
+rand_core = { version = "0.6.4", default-features = false }
 rsa = { version = "0.9.2", default-features = false, features = ["sha2"] }
 rustls = { version = "0.23.0", default-features = false }
 sec1 = { version = "0.7.3", default-features = false, features = ["pkcs8", "pem"] }