diff --git a/libs/androidfw/AssetManager2.cpp b/libs/androidfw/AssetManager2.cpp
index 27b121b..2864c68 100644
--- a/libs/androidfw/AssetManager2.cpp
+++ b/libs/androidfw/AssetManager2.cpp
@@ -1356,21 +1356,22 @@
 
 void AssetManager2::RebuildFilterList() {
   for (PackageGroup& group : package_groups_) {
-    for (ConfiguredPackage& impl : group.packages_) {
-      impl.filtered_configs_.clear();
-
+    for (ConfiguredPackage& package : group.packages_) {
+      package.filtered_configs_.forEachItem([](auto, auto& fcg) { fcg.type_entries.clear(); });
       // Create the filters here.
-      impl.loaded_package_->ForEachTypeSpec([&](const TypeSpec& type_spec, uint8_t type_id) {
+      package.loaded_package_->ForEachTypeSpec([&](const TypeSpec& type_spec, uint8_t type_id) {
         FilteredConfigGroup* group = nullptr;
         for (const auto& type_entry : type_spec.type_entries) {
           if (type_entry.config.match(configuration_)) {
             if (!group) {
-              group = &impl.filtered_configs_.editItemAt(type_id - 1);
+              group = &package.filtered_configs_.editItemAt(type_id - 1);
             }
             group->type_entries.push_back(&type_entry);
           }
         }
       });
+      package.filtered_configs_.trimBuckets(
+          [](const auto& fcg) { return fcg.type_entries.empty(); });
     }
   }
 }
diff --git a/libs/androidfw/include/androidfw/ByteBucketArray.h b/libs/androidfw/include/androidfw/ByteBucketArray.h
index 05a2c4d..ca0a9ed 100644
--- a/libs/androidfw/include/androidfw/ByteBucketArray.h
+++ b/libs/androidfw/include/androidfw/ByteBucketArray.h
@@ -17,6 +17,7 @@
 #ifndef __BYTE_BUCKET_ARRAY_H
 #define __BYTE_BUCKET_ARRAY_H
 
+#include <algorithm>
 #include <cstdint>
 #include <cstring>
 
@@ -36,15 +37,11 @@
   }
 
   ~ByteBucketArray() {
-    clear();
+    deleteBuckets();
   }
 
   void clear() {
-    for (size_t i = 0; i < kNumBuckets; i++) {
-      if (buckets_[i] != NULL) {
-        delete[] buckets_[i];
-      }
-    }
+    deleteBuckets();
     memset(buckets_, 0, sizeof(buckets_));
   }
 
@@ -59,7 +56,7 @@
 
     uint8_t bucket_index = static_cast<uint8_t>(index) >> 4;
     T* bucket = buckets_[bucket_index];
-    if (bucket == NULL) {
+    if (bucket == nullptr) {
       return default_;
     }
     return bucket[0x0f & static_cast<uint8_t>(index)];
@@ -70,9 +67,9 @@
                           << ") with size=" << size();
 
     uint8_t bucket_index = static_cast<uint8_t>(index) >> 4;
-    T* bucket = buckets_[bucket_index];
-    if (bucket == NULL) {
-      bucket = buckets_[bucket_index] = new T[kBucketSize]();
+    T*& bucket = buckets_[bucket_index];
+    if (bucket == nullptr) {
+      bucket = new T[kBucketSize]();
     }
     return bucket[0x0f & static_cast<uint8_t>(index)];
   }
@@ -86,9 +83,42 @@
     return true;
   }
 
+  template <class Func>
+  void forEachItem(Func f) {
+    for (size_t i = 0; i < kNumBuckets; i++) {
+      const auto bucket = buckets_[i];
+      if (bucket != nullptr) {
+        for (size_t j = 0; j < kBucketSize; j++) {
+          f((i << 4) | j, bucket[j]);
+        }
+      }
+    }
+  }
+
+  template <class Func>
+  void trimBuckets(Func isEmptyFunc) {
+    for (size_t i = 0; i < kNumBuckets; i++) {
+      const auto bucket = buckets_[i];
+      if (bucket != nullptr) {
+        if (std::all_of(bucket, bucket + kBucketSize, isEmptyFunc)) {
+          delete[] bucket;
+          buckets_[i] = nullptr;
+        }
+      }
+    }
+  }
+
  private:
   enum { kNumBuckets = 16, kBucketSize = 16 };
 
+  void deleteBuckets() {
+    for (size_t i = 0; i < kNumBuckets; i++) {
+      if (buckets_[i] != nullptr) {
+        delete[] buckets_[i];
+      }
+    }
+  }
+
   T* buckets_[kNumBuckets];
   static inline const T default_ = {};
 };
diff --git a/libs/androidfw/tests/ByteBucketArray_test.cpp b/libs/androidfw/tests/ByteBucketArray_test.cpp
index 5d464c7..9c36cfb 100644
--- a/libs/androidfw/tests/ByteBucketArray_test.cpp
+++ b/libs/androidfw/tests/ByteBucketArray_test.cpp
@@ -52,4 +52,57 @@
   }
 }
 
+TEST(ByteBucketArrayTest, TestForEach) {
+  ByteBucketArray<int> bba;
+  ASSERT_TRUE(bba.set(0, 1));
+  ASSERT_TRUE(bba.set(10, 2));
+  ASSERT_TRUE(bba.set(26, 3));
+  ASSERT_TRUE(bba.set(129, 4));
+  ASSERT_TRUE(bba.set(234, 5));
+
+  int count = 0;
+  bba.forEachItem([&count](auto i, auto val) {
+    ++count;
+    switch (i) {
+      case 0:
+        EXPECT_EQ(1, val);
+        break;
+      case 10:
+        EXPECT_EQ(2, val);
+        break;
+      case 26:
+        EXPECT_EQ(3, val);
+        break;
+      case 129:
+        EXPECT_EQ(4, val);
+        break;
+      case 234:
+        EXPECT_EQ(5, val);
+        break;
+      default:
+        EXPECT_EQ(0, val);
+        break;
+    }
+  });
+  ASSERT_EQ(4 * 16, count);
+}
+
+TEST(ByteBucketArrayTest, TestTrimBuckets) {
+  ByteBucketArray<int> bba;
+  ASSERT_TRUE(bba.set(0, 1));
+  ASSERT_TRUE(bba.set(255, 2));
+  {
+    bba.trimBuckets([](auto val) { return val < 2; });
+    int count = 0;
+    bba.forEachItem([&count](auto, auto) { ++count; });
+    ASSERT_EQ(1 * 16, count);
+  }
+  {
+    bba.trimBuckets([](auto val) { return val < 3; });
+    int count = 0;
+    bba.forEachItem([&count](auto, auto) { ++count; });
+    ASSERT_EQ(0, count);
+  }
+}
+
 }  // namespace android