fix: avoid implicit clang target on native builds

src/core/build/engine.rs

@@ -609,10 +609,14 @@ fn build_project_at_inner(
         tc_as.as_deref(),
     );
     let resolved_linker = resolve_tool("DCR_LD", tc_ld.as_deref());
-    prepend_clang_target_flag(&mut build_cflags, build_target, &resolved_compiler);
+    // The host triple is still used for native target-specific configuration and
+    // artifact paths, but native Clang must select the platform SDK implicitly.
+    // Pass --target only when the user/config explicitly requested a target.
+    let compiler_target = if explicit_target { build_target } else { None };
+    prepend_clang_target_flag(&mut build_cflags, compiler_target, &resolved_compiler);
     prepend_clang_target_flag(
         &mut build_ldflags,
-        build_target,
+        compiler_target,
         resolved_linker.as_deref().unwrap_or(&resolved_compiler),
     );
     let resolved_archiver = resolve_tool("DCR_AR", tc_ar.as_deref());

src/utils/build.rs

@@ -782,6 +782,13 @@ mod tests {
         assert_eq!(flags, vec!["-O2".to_string()]);
     }
 
+    #[test]
+    fn native_clang_target_is_not_added_without_explicit_target() {
+        let mut flags = vec!["-O3".to_string()];
+        prepend_clang_target_flag(&mut flags, None, "clang");
+        assert_eq!(flags, vec!["-O3".to_string()]);
+    }
+
     /// Test for parse_version_parts function.
     #[test]
     fn parse_version_parts() {