fix for cpp version compatibility

Author: ciaranra

.github/workflows/python-release.yml

@@ -91,17 +91,28 @@ jobs:
 
       - name: Build wheel
         uses: PyO3/maturin-action@v1
+        env:
+          # Set C++14 standard for cross-compilation compatibility
+          CXXFLAGS: "-std=c++14"
+          CXX_aarch64_unknown_linux_gnu: "aarch64-linux-gnu-g++"
+          CXXFLAGS_aarch64_unknown_linux_gnu: "-std=c++14"
         with:
           command: build
           args: --release --out dist --interpreter python3.10
           working-directory: python/pecos-rslib
           target: ${{ matrix.architecture == 'aarch64' && (matrix.os == 'macos-latest' && 'aarch64-apple-darwin' || 'aarch64-unknown-linux-gnu') || (matrix.os == 'macos-latest' && 'x86_64-apple-darwin' || '') }}
           manylinux: auto
           before-script-linux: |
+            # Install dependencies and ensure modern C++ compiler
             if command -v yum &> /dev/null; then
-              yum install -y openssl-devel
+              yum install -y openssl-devel gcc-c++ libstdc++-devel
+              # For manylinux, install newer gcc if needed
+              if [ "${{ matrix.architecture }}" = "aarch64" ]; then
+                yum install -y devtoolset-10-gcc-c++ || true
+                source /opt/rh/devtoolset-10/enable 2>/dev/null || true
+              fi
             elif command -v apt-get &> /dev/null; then
-              apt-get update && apt-get install -y libssl-dev pkg-config
+              apt-get update && apt-get install -y libssl-dev pkg-config g++ libstdc++-11-dev
             else
               echo "No supported package manager found"
               exit 1

crates/pecos-cppsparsesim/build.rs

@@ -1,18 +1,47 @@
 fn main() {
     // Build C++ source files
-    cc::Build::new()
+    let mut build = cc::Build::new();
+    build
         .cpp(true)
         .file("src/sparsesim.cpp")
         .file("src/cxx_shim.cpp")
-        .include("src")
-        .std("c++14")
-        .compile("sparsesim");
+        .include("src");
+    
+    // Use C++14 or newer to avoid issues with older cross-compilers
+    // that don't fully support C++11 type traits like is_trivially_move_constructible
+    let target = std::env::var("TARGET").unwrap_or_default();
+    
+    // For cross-compilation (especially aarch64), we need at least C++14
+    // to ensure type traits are available
+    if target.contains("aarch64") || target.contains("arm") {
+        // Try C++17 first, fall back to C++14
+        if !build.is_flag_supported("-std=c++17").unwrap_or(false) {
+            build.std("c++14");
+        } else {
+            build.std("c++17");
+        }
+    } else {
+        build.std("c++14");
+    }
+    
+    build.compile("sparsesim");
 
-    // Generate cxx bridge code
-    cxx_build::bridge("src/lib.rs")
-        .file("src/cxx_shim.cpp")
-        .std("c++14")
-        .compile("cppsparsesim-bridge");
+    // Generate cxx bridge code with same C++ standard
+    let mut bridge = cxx_build::bridge("src/lib.rs");
+    bridge.file("src/cxx_shim.cpp");
+    
+    // Match the same C++ standard for cxx bridge
+    if target.contains("aarch64") || target.contains("arm") {
+        if !bridge.is_flag_supported("-std=c++17").unwrap_or(false) {
+            bridge.std("c++14");
+        } else {
+            bridge.std("c++17");
+        }
+    } else {
+        bridge.std("c++14");
+    }
+    
+    bridge.compile("cppsparsesim-bridge");
 
     // Tell cargo to rerun if source files change
     println!("cargo:rerun-if-changed=src/lib.rs");

crates/pecos-ldpc-decoders/build_ldpc.rs

@@ -191,12 +191,26 @@ fn build_cxx_bridge(ldpc_dir: &Path) -> Result<()> {
     let mut build = cxx_build::bridge("src/bridge.rs");
     build
         .file("src/bridge.cpp")
-        .std("c++17")
         .include(&src_cpp_dir)
         .include(&include_dir)
         .include(include_dir.join("robin_map"))
         .include(include_dir.join("rapidcsv"))
         .include("include");
+    
+    // Use C++17 when available, fall back to C++14 for older compilers
+    // This helps with cross-compilation where older toolchains may not fully support C++17
+    let target = env::var("TARGET").unwrap_or_default();
+    if target.contains("aarch64") || target.contains("arm") {
+        // For ARM targets, check what's supported
+        if !build.is_flag_supported("-std=c++17").unwrap_or(false) {
+            build.std("c++14");
+        } else {
+            build.std("c++17");
+        }
+    } else {
+        // For other targets, use C++17
+        build.std("c++17");
+    }
 
     // Report ccache/sccache configuration
     report_cache_config();