chore: make sure that the documention is available on doc.rs

.circleci/config.yml

@@ -149,6 +149,21 @@ jobs:
       - run:
           name: Run cargo release build
           command: cargo build --workspace --release
+  rustdoc:
+    executor: default
+    environment:
+      # Making sure that the documentation can be built without having the NVIDIA toolkit
+      # installed.
+      DOCS_RS: true
+    steps:
+      - *restore-workspace
+      - *restore-cache
+      - run: echo 'export PATH="$HOME:~/.cargo/bin:$PATH"' >> $BASH_ENV && source $BASH_ENV
+      - run:
+          name: Run rustdoc
+          command: |
+            cargo rustdoc --package ec-gpu --all-features -- -D warnings
+            cargo rustdoc --package ec-gpu-gen --all-features -- -D warnings
 
 workflows:
   version: 2.1
@@ -206,3 +221,6 @@ workflows:
       - build:
           requires:
             - cargo_fetch
+      - rustdoc:
+          requires:
+            - cargo_fetch

ec-gpu-gen/build.rs

@@ -18,6 +18,13 @@ fn main() {
     #[path = "src/source.rs"]
     mod source;
 
+    // This is a hack for the case when the documentation is built on docs.rs. For the
+    // documentation  we don't need a properly compiled kernel, but just some arbitrary bytes.
+    if env::var("DOCS_RS").is_ok() {
+        println!("cargo:rustc-env=CUDA_KERNEL_FATBIN=../build.rs");
+        return;
+    }
+
     let kernel_source = source::gen_source::<Bls12, source::Limb32>();
 
     let out_dir = env::var("OUT_DIR").expect("OUT_DIR was not set.");
@@ -69,7 +76,7 @@ fn main() {
             .arg(&fatbin_path)
             .arg(&source_path)
             .status()
-            .expect("Cannot run nvcc.");
+            .expect("Cannot run nvcc. Install the NVIDIA toolkit or disable the `cuda` feature.");
 
         if !status.success() {
             panic!(