diff --git a/table/block.h b/table/block.h
index 470e52322..c6c03a300 100644
--- a/table/block.h
+++ b/table/block.h
@@ -49,8 +49,11 @@ class BlockReadAmpBitmap {
     }
 
     // num_bits_needed = ceil(block_size / bytes_per_bit)
-    size_t num_bits_needed = (block_size >> bytes_per_bit_pow_) +
-                             (block_size % (1 << bytes_per_bit_pow_) != 0);
+    size_t num_bits_needed =
+        (block_size >> static_cast<size_t>(bytes_per_bit_pow_)) +
+        (block_size % (static_cast<size_t>(1)
+                       << static_cast<size_t>(bytes_per_bit_pow_)) !=
+         0);
 
     // bitmap_size = ceil(num_bits_needed / kBitsPerEntry)
     size_t bitmap_size = (num_bits_needed / kBitsPerEntry) +
diff --git a/util/threadpool_imp.cc b/util/threadpool_imp.cc
index 1c8153477..128124cb2 100644
--- a/util/threadpool_imp.cc
+++ b/util/threadpool_imp.cc
@@ -38,7 +38,7 @@ namespace {
 
 struct Lock {
   std::unique_lock<std::mutex> ul_;
-  explicit Lock(const std::mutex& m) : ul_(m, std::defer_lock) {}
+  explicit Lock(std::mutex& m) : ul_(m, std::defer_lock) {}
 };
 
 using Condition = std::condition_variable;