Improve Fuzz GitHub Actions CI (#1080)

* add separate fuzz build step

* improve fuzz caching

* separate build and test phases in CI

* properly build only tests

* separate build and test commands in ASAN test job

* remove second '--tests' arg

.github/workflows/rust.yml

@@ -67,6 +67,10 @@ jobs:
         run: rustup show
       - name: "Add Rust Component: `rust-src`"
         run: rustup component add rust-src --toolchain nightly-x86_64-unknown-linux-gnu
+      - name: Build Tests
+        env:
+          RUSTFLAGS: "--cfg debug_assertions -Zsanitizer=address"
+        run: cargo build --tests --workspace -Zbuild-std --target x86_64-unknown-linux-gnu
       - name: Test
         env:
           RUSTFLAGS: "--cfg debug_assertions -Zsanitizer=address"
@@ -95,10 +99,18 @@ jobs:
           restore-keys: ${{ runner.os }}-${{ github.job }}-
       - name: Checkout Submodules
         run: git submodule update --init --recursive
+      - name: Build (default features)
+        env:
+          RUSTFLAGS: "--cfg debug_assertions"
+        run: cargo build --tests --workspace --release
       - name: Test (default features)
         env:
           RUSTFLAGS: "--cfg debug_assertions"
         run: cargo test --workspace --release
+      - name: Build (all features)
+        env:
+          RUSTFLAGS: "--cfg debug_assertions"
+        run: cargo build --tests --workspace --release --all-features
       - name: Test (all features)
         env:
           RUSTFLAGS: "--cfg debug_assertions"
@@ -200,7 +212,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             ~/target/
-            ~/fuzz/target/
+            ~/target/x86_64-unknown-linux-gnu/
+            ~/target/x86_64-unknown-linux-gnu/release/
             ~/fuzz/corpus/translate/
             ~/fuzz/curpus/translate_metered/
           key: ${{ runner.os }}-${{ github.job }}-${{ hashFiles('**/Cargo.lock') }}
@@ -212,6 +225,8 @@ jobs:
           # Note: We use `|| true` because cargo install returns an error
           #       if cargo-udeps was already installed on the CI runner.
           cargo install cargo-fuzz || true
+      - name: Build Fuzzing
+        run: cargo fuzz build translate
       - name: Fuzz (Translation)
         run: cargo fuzz run translate -j 2 --verbose -- -max_total_time=60 # 1 minute of fuzzing
       - name: Fuzz (Translation) + fuel
@@ -233,6 +248,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             ~/target/
+            ~/target/x86_64-unknown-linux-gnu/
+            ~/target/x86_64-unknown-linux-gnu/release/
             ~/target/release/
             ~/target/debug/
             ~/fuzz/corpus/execute/
@@ -245,6 +262,8 @@ jobs:
           # Note: We use `|| true` because cargo install returns an error
           #       if cargo-udeps was already installed on the CI runner.
           cargo install cargo-fuzz || true
+      - name: Build Fuzzing
+        run: cargo fuzz build execute
       - name: Fuzz (Execution)
         run: cargo fuzz run execute -j 2 --verbose -- -max_total_time=120 # 2 minutes of fuzzing
 
@@ -264,6 +283,8 @@ jobs:
             ~/.cargo/registry/cache/
             ~/.cargo/git/db/
             ~/target/
+            ~/target/x86_64-unknown-linux-gnu/
+            ~/target/x86_64-unknown-linux-gnu/release/
             ~/target/release/
             ~/target/debug/
             ~/fuzz/corpus/execute/
@@ -276,6 +297,8 @@ jobs:
           # Note: We use `|| true` because cargo install returns an error
           #       if cargo-udeps was already installed on the CI runner.
           cargo install cargo-fuzz || true
+      - name: Build Fuzzing
+        run: cargo fuzz build differential
       - name: Fuzz (Differential)
         run: cargo fuzz run differential -j 2 --verbose -- -max_total_time=120 # 2 minutes of fuzzing