diff --git a/src/arena_allocator.cpp b/src/arena_allocator.cpp
index df4a0d4..d4642dd 100644
--- a/src/arena_allocator.cpp
+++ b/src/arena_allocator.cpp
@@ -1,5 +1,6 @@
 #include "arena_allocator.hpp"
 #include <cassert>
+#include <iomanip>
 
 ArenaAllocator::~ArenaAllocator() {
   while (current_block_) {
diff --git a/src/arena_allocator.hpp b/src/arena_allocator.hpp
index 6467be6..ca81377 100644
--- a/src/arena_allocator.hpp
+++ b/src/arena_allocator.hpp
@@ -5,7 +5,6 @@
 #include <cstdint>
 #include <cstdlib>
 #include <cstring>
-#include <iomanip>
 #include <iostream>
 #include <new>
 #include <type_traits>
@@ -595,13 +594,11 @@ public:
   T *allocate(size_type n) {
     if (n == 0)
       return nullptr;
-    return static_cast<T *>(arena_->allocate_raw(n * sizeof(T), alignof(T)));
+    return arena_->allocate<T>(n);
   }
 
-  void deallocate(T *ptr, size_type n) noexcept {
+  void deallocate(T *, size_type) noexcept {
     // Arena allocator doesn't support individual deallocation
-    (void)ptr;
-    (void)n;
   }
 
   template <typename U>