diff --git a/faiss/impl/NNDescent.cpp b/faiss/impl/NNDescent.cpp
index 8878349ff6..b609aba390 100644
--- a/faiss/impl/NNDescent.cpp
+++ b/faiss/impl/NNDescent.cpp
@@ -195,8 +195,9 @@ void NNDescent::update() {
         int l = 0;
 
         while ((l < maxl) && (c < S)) {
-            if (nn.pool[l].flag)
+            if (nn.pool[l].flag) {
                 ++c;
+            }
             ++l;
         }
         nn.M = l;
@@ -305,8 +306,9 @@ void NNDescent::generate_eval_set(
     for (int i = 0; i < c.size(); i++) {
         std::vector<Neighbor> tmp;
         for (int j = 0; j < N; j++) {
-            if (c[i] == j)
+            if (c[i] == j) {
                 continue; // skip itself
+            }
             float dist = qdis.symmetric_dis(c[i], j);
             tmp.push_back(Neighbor(j, dist, true));
         }
@@ -360,8 +362,9 @@ void NNDescent::init_graph(DistanceComputer& qdis) {
 
             for (int j = 0; j < S; j++) {
                 int id = tmp[j];
-                if (id == i)
+                if (id == i) {
                     continue;
+                }
                 float dist = qdis.symmetric_dis(i, id);
 
                 graph[i].pool.push_back(Neighbor(id, dist, true));
@@ -418,30 +421,30 @@ void NNDescent::search(
         float* dists,
         VisitedTable& vt) const {
     FAISS_THROW_IF_NOT_MSG(has_built, "The index is not build yet.");
-    int L = std::max(search_L, topk);
+    int L_2 = std::max(search_L, topk);
 
     // candidate pool, the K best items is the result.
-    std::vector<Neighbor> retset(L + 1);
+    std::vector<Neighbor> retset(L_2 + 1);
 
-    // Randomly choose L points to initialize the candidate pool
-    std::vector<int> init_ids(L);
+    // Randomly choose L_2 points to initialize the candidate pool
+    std::vector<int> init_ids(L_2);
     std::mt19937 rng(random_seed);
 
-    gen_random(rng, init_ids.data(), L, ntotal);
-    for (int i = 0; i < L; i++) {
+    gen_random(rng, init_ids.data(), L_2, ntotal);
+    for (int i = 0; i < L_2; i++) {
         int id = init_ids[i];
         float dist = qdis(id);
         retset[i] = Neighbor(id, dist, true);
     }
 
     // Maintain the candidate pool in ascending order
-    std::sort(retset.begin(), retset.begin() + L);
+    std::sort(retset.begin(), retset.begin() + L_2);
 
     int k = 0;
 
-    // Stop until the smallest position updated is >= L
-    while (k < L) {
-        int nk = L;
+    // Stop until the smallest position updated is >= L_2
+    while (k < L_2) {
+        int nk = L_2;
 
         if (retset[k].flag) {
             retset[k].flag = false;
@@ -449,25 +452,28 @@ void NNDescent::search(
 
             for (int m = 0; m < K; ++m) {
                 int id = final_graph[n * K + m];
-                if (vt.get(id))
+                if (vt.get(id)) {
                     continue;
+                }
 
                 vt.set(id);
                 float dist = qdis(id);
-                if (dist >= retset[L - 1].distance)
+                if (dist >= retset[L_2 - 1].distance) {
                     continue;
+                }
 
                 Neighbor nn(id, dist, true);
-                int r = insert_into_pool(retset.data(), L, nn);
+                int r = insert_into_pool(retset.data(), L_2, nn);
 
                 if (r < nk)
                     nk = r;
             }
         }
-        if (nk <= k)
+        if (nk <= k) {
             k = nk;
-        else
+        } else {
             ++k;
+        }
     }
     for (size_t i = 0; i < topk; i++) {
         indices[i] = retset[i].id;