add QEMU CI support

.github/workflows/checks.yaml

@@ -84,7 +84,7 @@ jobs:
         with:
             shared-key: "${{matrix.rust}}-${{matrix.target}}"
       - name: cargo build
-        run: cargo build ${{ matrix.features }}
+        run: cargo build --target ${{matrix.target}} ${{ matrix.features }}
       - name: cargo nextest # reports segfaults in a helpful way
         run: cargo nextest run --target ${{matrix.target}} ${{ matrix.features }} --no-fail-fast
         env:
@@ -101,6 +101,59 @@ jobs:
           files: lcov.info
           fail_ci_if_error: false
 
+  build-qemu:
+    name: QEMU build & test
+    runs-on: "${{ matrix.os }}"
+    strategy:
+      matrix:
+        include:
+          - rust: stable
+            os: ubuntu-latest
+            features: ""
+            target: "s390x-unknown-linux-gnu"
+            gcc: "s390x-linux-gnu-gcc"
+          - rust: stable
+            os: ubuntu-latest
+            features: ""
+            target: "i686-unknown-linux-gnu"
+            gcc: "i686-linux-gnu-gcc"
+    steps:
+      - uses: actions/checkout@v2
+      - uses: awalsh128/cache-apt-pkgs-action@latest
+        with:
+          packages: qemu qemu-user qemu-user-static qemu-system-s390x gcc-s390x-linux-gnu gcc-i686-linux-gnu
+          version: 1.0
+      - name: Checkout sources
+        uses: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11
+        with:
+          persist-credentials: false
+      - name: Copy QEMU Cargo Config
+        run: |
+          mkdir -p .cargo
+          cp qemu-cargo-config.toml .cargo/config.toml
+      - name: Install toolchain
+        uses: dtolnay/rust-toolchain@be73d7920c329f220ce78e0234b8f96b7ae60248
+        with:
+          toolchain: "stable"
+          targets: "${{ matrix.target }}"
+      - name: target
+        run: "rustc -vV | sed -n 's|host: ||p'"
+      - name: Rust cache
+        uses: Swatinem/rust-cache@3cf7f8cc28d1b4e7d01e3783be10a97d55d483c8
+        with:
+            shared-key: "${{matrix.rust}}-${{matrix.target}}"
+      - name: Install cargo-nextest
+        uses: taiki-e/install-action@56ab7930c591507f833cbaed864d201386d518a8
+        with:
+          tool: cargo-nextest
+      - name: cargo build
+        run: cargo build --target ${{matrix.target}} ${{ matrix.features }}
+      - name: cargo nextest # reports segfaults in a helpful way
+        run: cargo nextest run -p zlib-rs --target ${{matrix.target}} ${{ matrix.features }}
+        env:
+          RUST_BACKTRACE: 1
+          CC: ${{matrix.gcc}}
+
   clippy:
     name: Clippy
     strategy:

qemu-cargo-config.toml

@@ -0,0 +1,8 @@
+# gets copied to .cargo/config.toml on CI, meant to run tests under qemu
+
+[target.s390x-unknown-linux-gnu]
+runner = "qemu-s390x -L /usr/s390x-linux-gnu"
+linker = "s390x-linux-gnu-gcc"
+
+[target.i686-unknown-linux-gnu]
+linker = "i686-linux-gnu-gcc"

test-libz-rs-sys/src/deflate.rs

@@ -716,6 +716,10 @@ fn deflate_bound_gzip_header() {
 }
 
 #[test]
+#[cfg_attr(
+    target_endian = "big",
+    ignore = "we don't support DFLTCC, which changes the bounds in zlib-ng"
+)]
 fn test_compress_bound_windows() {
     let source_len = 4294967289 as core::ffi::c_ulong;
 
@@ -726,6 +730,10 @@ fn test_compress_bound_windows() {
 }
 
 #[test]
+#[cfg_attr(
+    target_endian = "big",
+    ignore = "we don't support DFLTCC, which changes the bounds in zlib-ng"
+)]
 fn test_compress_bound() {
     ::quickcheck::quickcheck(test as fn(_) -> _);
 
@@ -1965,17 +1973,21 @@ mod fuzz_based_tests {
     const LCET10: &str = include_str!("test-data/lcet10.txt");
 
     #[test]
-    #[cfg_attr(miri, ignore)]
+    #[cfg_attr(
+        not(any(target_arch = "x86_64", target_arch = "aarch64")),
+        ignore = "https://github.com/memorysafety/zlib-rs/issues/91"
+    )]
+    #[cfg_attr(miri, ignore = "too slow")]
     fn compress_lcet10() {
         fuzz_based_test(LCET10.as_bytes(), DeflateConfig::default(), &[])
     }
 
     #[test]
     #[cfg_attr(
-        target_arch = "aarch64",
+        not(target_arch = "x86_64"),
         ignore = "https://github.com/memorysafety/zlib-rs/issues/91"
     )]
-    #[cfg_attr(miri, ignore)]
+    #[cfg_attr(miri, ignore = "too slow")]
     fn compress_paper_100k() {
         let mut config = DeflateConfig::default();
 

zlib-rs/src/deflate.rs

@@ -4059,24 +4059,24 @@ mod test {
             strategy: Strategy::Default,
         };
 
-        let _x86_64 = [
+        let x86 = [
             24, 149, 99, 96, 96, 96, 96, 208, 6, 17, 112, 138, 129, 193, 128, 1, 29, 24, 50, 208,
             1, 200, 146, 169, 79, 24, 74, 59, 96, 147, 52, 71, 22, 70, 246, 88, 26, 94, 80, 128,
             83, 6, 162, 219, 144, 76, 183, 210, 5, 8, 67, 105, 7, 108, 146, 230, 216, 133, 145,
             129, 22, 3, 3, 131, 17, 3, 0, 3, 228, 25, 128,
         ];
 
-        let _aarch64 = [
+        let other = [
             24, 149, 99, 96, 96, 96, 96, 208, 6, 17, 112, 138, 129, 193, 128, 1, 29, 24, 50, 208,
             1, 200, 146, 169, 79, 24, 74, 59, 96, 147, 52, 71, 22, 70, 246, 88, 26, 94, 80, 128,
             83, 6, 162, 219, 144, 76, 183, 210, 5, 8, 67, 105, 36, 159, 35, 128, 57, 118, 97, 100,
             160, 197, 192, 192, 96, 196, 0, 0, 3, 228, 25, 128,
         ];
 
-        #[cfg(target_arch = "x86_64")]
-        fuzz_based_test(&input, config, &_x86_64);
-
-        #[cfg(target_arch = "aarch64")]
-        fuzz_based_test(&input, config, &_aarch64);
+        if cfg!(any(target_arch = "x86_64", target_arch = "x86")) {
+            fuzz_based_test(&input, config, &x86);
+        } else {
+            fuzz_based_test(&input, config, &other);
+        }
     }
 }