diff --git a/llama-util.h b/llama-util.h
index 9c38bddd0..30a6c0eb5 100644
--- a/llama-util.h
+++ b/llama-util.h
@@ -16,6 +16,7 @@
 #include <vector>
 #include <map>
 #include <unordered_map>
+#include <memory>
 #include <stdexcept>
 
 #ifdef __has_include
@@ -546,7 +547,7 @@ typedef llama_buffer llama_ctx_buffer;
 struct llama_trie_node {
     llama_trie_node(): is_terminator(false) {}
 
-    std::unordered_map<char, llama_trie_node*> children;
+    std::unordered_map<char, std::unique_ptr<llama_trie_node>> children;
     bool is_terminator;
 };
 
@@ -561,24 +562,24 @@ public:
             return;
         }
 
-        llama_trie_node *ref = root_;
+        llama_trie_node *ref = root_.get();
         for (char c : word) {
             if (ref->children.find(c) == ref->children.end()) {
-                ref->children[c] = new llama_trie_node();
+                ref->children[c].reset(new llama_trie_node());
             }
-            ref = ref->children[c];
+            ref = ref->children[c].get();
         }
         ref->is_terminator = true;
     }
 
     // Will look for the words added to the trie within `text`. Output is the boundaries of the words found.
     // Note that this trie will match the longest possible word first!
-    std::vector<int> split(const std::string & text) const {
-        std::map<int, llama_trie_node*> states;
-        std::vector<int> offsets{0};
+    std::vector<size_t> split(const std::string & text) const {
+        std::map<size_t, llama_trie_node*> states;
+        std::vector<size_t> offsets{0};
 
-        int skip = 0;
-        for (int current = 0; current < text.size(); current++) {
+        size_t skip = 0;
+        for (size_t current = 0; current < text.size(); current++) {
             char current_char = text[current];
             if (skip > 0 && current < skip) {
                 // Prevents the lookahead for matching twice
@@ -592,7 +593,7 @@ public:
 
             // In this case, we already have partial matches (But unfinished)
             for (auto state = states.begin(); state != states.end(); ) {
-                int start = state->first;
+                size_t start = state->first;
                 llama_trie_node *trie_pointer = state->second;
                 if (trie_pointer->is_terminator) {
                     // This is a final match, we need to reset and
@@ -603,11 +604,11 @@ public:
                     // Here we are also actively looking for other earlier partial
                     // matches
                     // "[CLS]", "L", we need to match CLS even if L is special
-                    int end = 0;
+                    size_t end = 0;
                     for (const auto & look : states) {
-                        int lookstart = look.first;
+                        size_t lookstart = look.first;
                         llama_trie_node *looktrie_pointer = look.second;
-                        int lookahead_index = 0;
+                        size_t lookahead_index = 0;
                         if (lookstart > start) {
                             // This partial match is later, we can stop looking
                             break;
@@ -633,7 +634,7 @@ public:
 
                         auto looktrie_pointer_it = looktrie_pointer->children.find(next_char);
                         while (looktrie_pointer_it != looktrie_pointer->children.end()) {
-                            looktrie_pointer = looktrie_pointer_it->second;
+                            looktrie_pointer = looktrie_pointer_it->second.get();
                             lookahead_index++;
                             if (looktrie_pointer->is_terminator) {
                                 start = lookstart;
@@ -660,7 +661,7 @@ public:
                 if (trie_pointer_it != trie_pointer->children.end()) {
                     // The current character being looked at has a match within the trie
                     // update the pointer (it will be stored back into states later).
-                    trie_pointer = trie_pointer_it->second;
+                    trie_pointer = trie_pointer_it->second.get();
                     states[start] = trie_pointer;
                     ++state;
                 } else {
@@ -679,18 +680,18 @@ public:
             // start keeping track of this partial match.
             auto children_it = root_->children.find(current_char);
             if (current >= skip && children_it != root_->children.end()) {
-                states[current] = children_it->second;
+                states[current] = children_it->second.get();
             }
         }
 
         // We have a cut at the end with states.
         for (const auto & state : states) {
-            int start = state.first;
+            size_t start = state.first;
             llama_trie_node *trie_pointer = state.second;
             if (trie_pointer->is_terminator) {
                 // This is a final match, we need to reset and
                 // store the results in `offsets`.
-                int end = text.size();
+                size_t end = text.size();
                 offsets.push_back(start);
                 offsets.push_back(end);
                 break;
@@ -702,7 +703,7 @@ public:
     }
 
 private:
-    llama_trie_node *root_;
+    std::unique_ptr<llama_trie_node> root_;
 };
 
 #endif
diff --git a/llama.cpp b/llama.cpp
index d7e0b3174..af12931e0 100644
--- a/llama.cpp
+++ b/llama.cpp
@@ -281,7 +281,7 @@ struct llama_vocab {
 
     llama_trie special_token_trie;
     std::unordered_map<token, id> special_token_to_id;
-    size_t max_special_token_length;
+    size_t max_special_token_length = 0;
 };
 
 struct llama_model {
@@ -578,7 +578,7 @@ struct llama_file_loader {
         vocab.special_token_to_id.reserve(hparams.n_vocab_sp);
 
         for (uint32_t i = 0; i < hparams.n_vocab_sp; i++) {
-            uint32_t token_id = file.read_u32();
+            llama_vocab::id token_id = file.read_u32();
             const auto & word = vocab.id_to_token[token_id].tok;
 
             vocab.special_token_trie.add(word);
@@ -2108,9 +2108,9 @@ static std::vector<llama_vocab::id> llama_tokenize(const llama_vocab & vocab, co
         return output;
     }
 
-    std::vector<int> offsets = vocab.special_token_trie.split(text);
-    int start = 0;
-    for (int end : offsets) {
+    std::vector<size_t> offsets = vocab.special_token_trie.split(text);
+    size_t start = 0;
+    for (size_t end : offsets) {
         if (start >= end) {
             continue;
         }