Handle cross-compilation in the duplicate crate check

Author: bjorn3

src/bootstrap/src/core/build_steps/compile.rs

@@ -2423,15 +2423,25 @@ pub fn add_to_sysroot(
     for (path, dependency_type) in builder.read_stamp_file(stamp) {
         let filename = path.file_name().unwrap().to_str().unwrap();
         let dst = match dependency_type {
-            DependencyType::Host => sysroot_host_dst,
-            DependencyType::Target => sysroot_dst,
+            DependencyType::Host => {
+                if sysroot_dst == sysroot_host_dst {
+                    // Only insert the part before the . to deduplicate different files for the same crate.
+                    // For example foo-1234.dll and foo-1234.dll.lib.
+                    crates.insert(filename.split_once('.').unwrap().0.to_owned(), path.clone());
+                }
+
+                sysroot_host_dst
+            }
+            DependencyType::Target => {
+                // Only insert the part before the . to deduplicate different files for the same crate.
+                // For example foo-1234.dll and foo-1234.dll.lib.
+                crates.insert(filename.split_once('.').unwrap().0.to_owned(), path.clone());
+
+                sysroot_dst
+            }
             DependencyType::TargetSelfContained => self_contained_dst,
         };
         builder.copy_link(&path, &dst.join(filename), FileType::Regular);
-
-        // Only insert the part before the . to deduplicate different files for the same crate.
-        // For example foo-1234.dll and foo-1234.dll.lib.
-        crates.insert(filename.split_once('.').unwrap().0.to_owned(), path);
     }
 
     // Check that none of the rustc_* crates have multiple versions. Otherwise using them from