diff --git a/src/common/chunkedvector.c b/src/common/chunkedvector.c
index 3311fbeb..3f06ba7d 100644
--- a/src/common/chunkedvector.c
+++ b/src/common/chunkedvector.c
@@ -1,12 +1,12 @@
 #include "pocketpy/common/chunkedvector.h"
-#include "pocketpy/config.h"
+#include "pocketpy/pocketpy.h"
 #include <assert.h>
 
 #if defined(_MSC_VER)
 #include <intrin.h>
 #endif
 
-inline static int c11_bit_length(unsigned long x) {
+PK_INLINE static int c11__bit_length(unsigned long x) {
 #if(defined(__clang__) || defined(__GNUC__))
     return x == 0 ? 0 : (int)sizeof(unsigned long) * 8 - __builtin_clzl(x);
 #elif defined(_MSC_VER)
@@ -36,7 +36,6 @@ void c11_chunkedvector__ctor(c11_chunkedvector* self, int elem_size, int initial
     self->initial_chunks = initial_chunks;
     void* chunks_data = PK_MALLOC(elem_size * ((1U << (unsigned int)initial_chunks) - 1));
     for(int i = 0; i < initial_chunks; i++) {
-        // TODO: optimize?
         c11_chunkedvector_chunk chunk = {.length = 0,
                                          .capacity = 1U << i,
                                          .data = (char*)chunks_data + elem_size * ((1U << i) - 1U)};
@@ -56,10 +55,11 @@ void c11_chunkedvector__dtor(c11_chunkedvector* self) {
 
 void* c11_chunkedvector__emplace(c11_chunkedvector* self) {
     if(self->length == self->capacity) {
-        #ifndef NDEBUG
-            c11_chunkedvector_chunk last_chunk = c11_vector__back(c11_chunkedvector_chunk, &self->chunks);
-            assert(last_chunk.capacity == last_chunk.length);
-        #endif
+#ifndef NDEBUG
+        c11_chunkedvector_chunk last_chunk =
+            c11_vector__back(c11_chunkedvector_chunk, &self->chunks);
+        assert(last_chunk.capacity == last_chunk.length);
+#endif
         c11_chunkedvector_chunk chunk = {
             .length = 0,
             .capacity = 1U << (unsigned int)self->chunks.length,
@@ -67,9 +67,14 @@ void* c11_chunkedvector__emplace(c11_chunkedvector* self) {
         self->capacity += chunk.capacity;
         c11_vector__push(c11_chunkedvector_chunk, &self->chunks, chunk);
     }
-    int last_chunk_index = c11_bit_length(self->length + 1) - 1;
+#if 1
+    int last_chunk_index = c11__bit_length(self->length + 1) - 1;
     c11_chunkedvector_chunk* last_chunk =
         c11__at(c11_chunkedvector_chunk, &self->chunks, last_chunk_index);
+#else
+    // This is not correct, because there is some pre-allocated chunks
+    c11_chunkedvector_chunk* last_chunk = &c11_vector__back(c11_chunkedvector_chunk, &self->chunks);
+#endif
     void* p = (char*)last_chunk->data + self->elem_size * last_chunk->length;
     last_chunk->length++;
     self->length++;
@@ -77,7 +82,7 @@ void* c11_chunkedvector__emplace(c11_chunkedvector* self) {
 }
 
 void* c11_chunkedvector__at(c11_chunkedvector* self, int index) {
-    int chunk_index = c11_bit_length(index + 1) - 1;
+    int chunk_index = c11__bit_length(index + 1) - 1;
     c11_chunkedvector_chunk* chunk = c11__at(c11_chunkedvector_chunk, &self->chunks, chunk_index);
     return (char*)chunk->data + (index + 1 - (1U << (unsigned int)chunk_index)) * self->elem_size;
 }