diff --git a/common/dictionary.h b/common/dictionary.h
index 3436362..fc47c1e 100644
--- a/common/dictionary.h
+++ b/common/dictionary.h
@@ -38,7 +38,7 @@
   uint8_t data[122784];
 } BrotliDictionary;
 
-BROTLI_COMMON_API extern const BrotliDictionary* BrotliGetDictionary();
+BROTLI_COMMON_API extern const BrotliDictionary* BrotliGetDictionary(void);
 
 #define BROTLI_MIN_DICTIONARY_WORD_LENGTH 4
 #define BROTLI_MAX_DICTIONARY_WORD_LENGTH 24
diff --git a/common/version.h b/common/version.h
index 2cf6133..10fe01f 100755
--- a/common/version.h
+++ b/common/version.h
@@ -13,7 +13,7 @@
    If library is dynamically linked, use BrotliDecoderVersion and
    BrotliEncoderVersion methods. */
 
-/* Semantic version, claculated as (MAJOR << 24) | (MINOR << 12) | PATCH */
+/* Semantic version, calculated as (MAJOR << 24) | (MINOR << 12) | PATCH */
 #define BROTLI_VERSION 0x1000000
 
 #endif  /* BROTLI_COMMON_VERSION_H_ */
diff --git a/dec/state.c b/dec/state.c
index bb37c77..27f4129 100644
--- a/dec/state.c
+++ b/dec/state.c
@@ -137,10 +137,9 @@
   BROTLI_FREE(s, s->context_modes);
   BROTLI_FREE(s, s->context_map);
   BROTLI_FREE(s, s->dist_context_map);
-
-  BrotliDecoderHuffmanTreeGroupRelease(s, &s->literal_hgroup);
-  BrotliDecoderHuffmanTreeGroupRelease(s, &s->insert_copy_hgroup);
-  BrotliDecoderHuffmanTreeGroupRelease(s, &s->distance_hgroup);
+  BROTLI_FREE(s, s->literal_hgroup.htrees);
+  BROTLI_FREE(s, s->insert_copy_hgroup.htrees);
+  BROTLI_FREE(s, s->distance_hgroup.htrees);
 }
 
 void BrotliDecoderStateCleanup(BrotliDecoderState* s) {
@@ -160,17 +159,11 @@
   HuffmanCode** p = (HuffmanCode**)BROTLI_ALLOC(s, code_size + htree_size);
   group->alphabet_size = (uint16_t)alphabet_size;
   group->num_htrees = (uint16_t)ntrees;
-  group->htrees = (HuffmanCode**)p;
+  group->htrees = p;
   group->codes = (HuffmanCode*)(&p[ntrees]);
   return !!p;
 }
 
-void BrotliDecoderHuffmanTreeGroupRelease(
-    BrotliDecoderState* s, HuffmanTreeGroup* group) {
-  BROTLI_FREE(s, group->htrees);
-  group->htrees = NULL;
-}
-
 #if defined(__cplusplus) || defined(c_plusplus)
 }  /* extern "C" */
 #endif
diff --git a/dec/state.h b/dec/state.h
index ace6002..5946124 100644
--- a/dec/state.h
+++ b/dec/state.h
@@ -242,8 +242,6 @@
 BROTLI_INTERNAL BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(
     BrotliDecoderState* s, HuffmanTreeGroup* group, uint32_t alphabet_size,
     uint32_t ntrees);
-BROTLI_INTERNAL void BrotliDecoderHuffmanTreeGroupRelease(
-    BrotliDecoderState* s, HuffmanTreeGroup* group);
 
 #if defined(__cplusplus) || defined(c_plusplus)
 }  /* extern "C" */
diff --git a/enc/backward_references_hq.c b/enc/backward_references_hq.c
index 6640faa..5150ae1 100755
--- a/enc/backward_references_hq.c
+++ b/enc/backward_references_hq.c
@@ -519,6 +519,7 @@
   return num_commands;
 }
 
+/* REQUIRES: nodes != NULL and len(nodes) >= num_bytes + 1 */
 void BrotliZopfliCreateCommands(const size_t num_bytes,
                                 const size_t block_start,
                                 const size_t max_backward_limit,
@@ -609,7 +610,7 @@
   return ComputeShortestPathFromNodes(num_bytes, nodes);
 }
 
-
+/* REQUIRES: nodes != NULL and len(nodes) >= num_bytes + 1 */
 size_t BrotliZopfliComputeShortestPath(MemoryManager* m,
                                        const BrotliDictionary* dictionary,
                                        size_t num_bytes,
diff --git a/enc/block_splitter_inc.h b/enc/block_splitter_inc.h
index 8574fb9..f932740 100644
--- a/enc/block_splitter_inc.h
+++ b/enc/block_splitter_inc.h
@@ -214,7 +214,6 @@
   size_t num_final_clusters;
   static const uint32_t kInvalidIndex = BROTLI_UINT32_MAX;
   uint32_t* new_index;
-  uint8_t max_type = 0;
   size_t i;
   uint32_t sizes[HISTOGRAMS_PER_BATCH] = { 0 };
   uint32_t new_clusters[HISTOGRAMS_PER_BATCH] = { 0 };
@@ -337,6 +336,7 @@
   {
     uint32_t cur_length = 0;
     size_t block_idx = 0;
+    uint8_t max_type = 0;
     for (i = 0; i < num_blocks; ++i) {
       cur_length += block_lengths[i];
       if (i + 1 == num_blocks ||
diff --git a/enc/encode.c b/enc/encode.c
index e16002c..dc0ddc1 100644
--- a/enc/encode.c
+++ b/enc/encode.c
@@ -1067,7 +1067,6 @@
       0, hasher_eff_size, BROTLI_TRUE);
   if (BROTLI_IS_OOM(m)) goto oom;
 
-
   while (ok && metablock_start < input_size) {
     const size_t metablock_end =
         BROTLI_MIN(size_t, input_size, metablock_start + max_metablock_size);
diff --git a/enc/hash_to_binary_tree_inc.h b/enc/hash_to_binary_tree_inc.h
index b2d5ea2..0b2554c 100755
--- a/enc/hash_to_binary_tree_inc.h
+++ b/enc/hash_to_binary_tree_inc.h
@@ -197,7 +197,7 @@
    sorted by strictly increasing length and (non-strictly) increasing
    distance. */
 static BROTLI_INLINE size_t FN(FindAllMatches)(HasherHandle handle,
-    const BrotliDictionary* dicionary, const uint8_t* data,
+    const BrotliDictionary* dictionary, const uint8_t* data,
     const size_t ring_buffer_mask, const size_t cur_ix,
     const size_t max_length, const size_t max_backward,
     const BrotliEncoderParams* params, BackwardMatch* matches) {
@@ -240,7 +240,7 @@
   }
   {
     size_t minlen = BROTLI_MAX(size_t, 4, best_len + 1);
-    if (BrotliFindAllStaticDictionaryMatches(dicionary,
+    if (BrotliFindAllStaticDictionaryMatches(dictionary,
         &data[cur_ix_masked], minlen, max_length, &dict_matches[0])) {
       size_t maxlen = BROTLI_MIN(
           size_t, BROTLI_MAX_STATIC_DICTIONARY_MATCH_LEN, max_length);
diff --git a/enc/literal_cost.c b/enc/literal_cost.c
index 2e78600..91c691c 100644
--- a/enc/literal_cost.c
+++ b/enc/literal_cost.c
@@ -38,12 +38,10 @@
   size_t counts[3] = { 0 };
   size_t max_utf8 = 1;  /* should be 2, but 1 compresses better. */
   size_t last_c = 0;
-  size_t utf8_pos = 0;
   size_t i;
   for (i = 0; i < len; ++i) {
     size_t c = data[(pos + i) & mask];
-    utf8_pos = UTF8Position(last_c, c, 2);
-    ++counts[utf8_pos];
+    ++counts[UTF8Position(last_c, c, 2)];
     last_c = c;
   }
   if (counts[2] < 500) {
@@ -65,7 +63,6 @@
   size_t in_window = BROTLI_MIN(size_t, window_half, len);
   size_t in_window_utf8[3] = { 0 };
 
-
   size_t i;
   {  /* Bootstrap histograms. */
     size_t last_c = 0;
diff --git a/include/brotli/port.h b/include/brotli/port.h
index ecb1db2..16c31d4 100755
--- a/include/brotli/port.h
+++ b/include/brotli/port.h
@@ -135,7 +135,6 @@
 #define BROTLI_NOINLINE
 #endif
 
-
 #if BROTLI_MODERN_COMPILER || __has_attribute(deprecated)
 #define BROTLI_DEPRECATED __attribute__((deprecated))
 #else