try more for musl builds

Author: GlenDC

boring-sys/build/main.rs

@@ -213,12 +213,26 @@ fn get_boringssl_cmake_config(config: &Config) -> cmake::Config {
         return boringssl_cmake;
     }
 
+    let target_is_musl = config.target.contains("unknown-linux-musl");
+    let using_zig = config
+        .env
+        .cc
+        .as_deref()
+        .and_then(|s| s.to_str())
+        .map(|s| s.contains("zig") || s.ends_with("zigcc") || s.ends_with("zigcxx"))
+        .unwrap_or_default();
+
     if should_use_cmake_cross_compilation(config) {
-        boringssl_cmake
-            .define("CMAKE_CROSSCOMPILING", "true")
-            .define("CMAKE_C_COMPILER_TARGET", &config.target)
-            .define("CMAKE_CXX_COMPILER_TARGET", &config.target)
-            .define("CMAKE_ASM_COMPILER_TARGET", &config.target);
+        boringssl_cmake.define("CMAKE_CROSSCOMPILING", "true");
+
+        // Do NOT set CMAKE_*_COMPILER_TARGET when using Zig.
+        // CMake turns these into `--target=<rust-triple>` which Zig cannot parse.
+        if !using_zig {
+            boringssl_cmake
+                .define("CMAKE_C_COMPILER_TARGET", &config.target)
+                .define("CMAKE_CXX_COMPILER_TARGET", &config.target)
+                .define("CMAKE_ASM_COMPILER_TARGET", &config.target);
+        }
     }
 
     if let Some(cc) = &config.env.cc {
@@ -343,22 +357,26 @@ fn get_boringssl_cmake_config(config: &Config) -> cmake::Config {
                     );
                 }
                 "aarch64" => {
-                    boringssl_cmake.define(
-                        "CMAKE_TOOLCHAIN_FILE",
-                        config
-                            .manifest_dir
-                            .join("cmake/aarch64-linux.cmake")
-                            .as_os_str(),
-                    );
+                    if !(target_is_musl && using_zig) {
+                        boringssl_cmake.define(
+                            "CMAKE_TOOLCHAIN_FILE",
+                            config
+                                .manifest_dir
+                                .join("cmake/aarch64-linux.cmake")
+                                .as_os_str(),
+                        );
+                    }
                 }
                 "arm" => {
-                    boringssl_cmake.define(
-                        "CMAKE_TOOLCHAIN_FILE",
-                        config
-                            .manifest_dir
-                            .join("cmake/armv7-linux.cmake")
-                            .as_os_str(),
-                    );
+                    if !(target_is_musl && using_zig) {
+                        boringssl_cmake.define(
+                            "CMAKE_TOOLCHAIN_FILE",
+                            config
+                                .manifest_dir
+                                .join("cmake/armv7-linux.cmake")
+                                .as_os_str(),
+                        );
+                    }
                 }
                 _ => {
                     println!(