diff --git a/faiss/IndexAdditiveQuantizer.cpp b/faiss/IndexAdditiveQuantizer.cpp
index a7ce3fce00..8dc6bcd167 100644
--- a/faiss/IndexAdditiveQuantizer.cpp
+++ b/faiss/IndexAdditiveQuantizer.cpp
@@ -527,7 +527,7 @@ void ResidualCoarseQuantizer::search(
         float* distances,
         idx_t* labels,
         const SearchParameters* params_in) const {
-    float beam_factor_2 = this->beam_factor;
+    float actual_beam_factor = this->beam_factor;
     if (params_in) {
         auto params =
                 dynamic_cast<const SearchParametersResidualCoarseQuantizer*>(
@@ -535,15 +535,15 @@ void ResidualCoarseQuantizer::search(
         FAISS_THROW_IF_NOT_MSG(
                 params,
                 "need SearchParametersResidualCoarseQuantizer parameters");
-        beam_factor_2 = params->beam_factor;
+        actual_beam_factor = params->beam_factor;
     }
 
-    if (beam_factor_2 < 0) {
+    if (actual_beam_factor < 0) {
         AdditiveCoarseQuantizer::search(n, x, k, distances, labels);
         return;
     }
 
-    int beam_size = int(k * beam_factor_2);
+    int beam_size = int(k * actual_beam_factor);
     if (beam_size > ntotal) {
         beam_size = ntotal;
     }
diff --git a/faiss/IndexIVFFastScan.cpp b/faiss/IndexIVFFastScan.cpp
index 6c140c554f..f95ad354a7 100644
--- a/faiss/IndexIVFFastScan.cpp
+++ b/faiss/IndexIVFFastScan.cpp
@@ -56,17 +56,17 @@ IndexIVFFastScan::IndexIVFFastScan() {
 
 void IndexIVFFastScan::init_fastscan(
         size_t M,
-        size_t nbits_2,
+        size_t nbits_init,
         size_t nlist,
         MetricType /* metric */,
         int bbs_2) {
     FAISS_THROW_IF_NOT(bbs_2 % 32 == 0);
-    FAISS_THROW_IF_NOT(nbits_2 == 4);
+    FAISS_THROW_IF_NOT(nbits_init == 4);
 
     this->M = M;
-    this->nbits = nbits_2;
+    this->nbits = nbits_init;
     this->bbs = bbs_2;
-    ksub = (1 << nbits_2);
+    ksub = (1 << nbits_init);
     M2 = roundup(M, 2);
     code_size = M2 / 2;
 
@@ -1028,11 +1028,11 @@ void IndexIVFFastScan::search_implem_12(
 
     // prepare the result handlers
 
-    int qbs2_2 = this->qbs2 ? this->qbs2 : 11;
+    int actual_qbs2 = this->qbs2 ? this->qbs2 : 11;
 
     std::vector<uint16_t> tmp_bias;
     if (biases.get()) {
-        tmp_bias.resize(qbs2_2);
+        tmp_bias.resize(actual_qbs2);
         handler.dbias = tmp_bias.data();
     }
 
@@ -1045,7 +1045,7 @@ void IndexIVFFastScan::search_implem_12(
         int list_no = qcs[i0].list_no;
         size_t i1 = i0 + 1;
 
-        while (i1 < qcs.size() && i1 < i0 + qbs2_2) {
+        while (i1 < qcs.size() && i1 < i0 + actual_qbs2) {
             if (qcs[i1].list_no != list_no) {
                 break;
             }
@@ -1065,7 +1065,7 @@ void IndexIVFFastScan::search_implem_12(
         std::vector<int> q_map(nc), lut_entries(nc);
         AlignedTable<uint8_t> LUT(nc * dim12);
         memset(LUT.get(), -1, nc * dim12);
-        int qbs_2 = pq4_preferred_qbs(nc);
+        int qbs_for_list = pq4_preferred_qbs(nc);
 
         for (size_t i = i0; i < i1; i++) {
             const QC& qc = qcs[i];
@@ -1077,7 +1077,11 @@ void IndexIVFFastScan::search_implem_12(
             }
         }
         pq4_pack_LUT_qbs_q_map(
-                qbs_2, M2, dis_tables.get(), lut_entries.data(), LUT.get());
+                qbs_for_list,
+                M2,
+                dis_tables.get(),
+                lut_entries.data(),
+                LUT.get());
 
         // access the inverted list
 
@@ -1093,7 +1097,13 @@ void IndexIVFFastScan::search_implem_12(
         handler.id_map = ids.get();
 
         pq4_accumulate_loop_qbs(
-                qbs_2, list_size, M2, codes.get(), LUT.get(), handler, scaler);
+                qbs_for_list,
+                list_size,
+                M2,
+                codes.get(),
+                LUT.get(),
+                handler,
+                scaler);
         // prepare for next loop
         i0 = i1;
     }
@@ -1231,11 +1241,11 @@ void IndexIVFFastScan::search_implem_14(
                 is_max, impl, n, k, local_dis.data(), local_idx.data(), sel));
         handler->begin(normalizers.get());
 
-        int qbs2_2 = this->qbs2 ? this->qbs2 : 11;
+        int actual_qbs2 = this->qbs2 ? this->qbs2 : 11;
 
         std::vector<uint16_t> tmp_bias;
         if (biases.get()) {
-            tmp_bias.resize(qbs2_2);
+            tmp_bias.resize(actual_qbs2);
             handler->dbias = tmp_bias.data();
         }
 
@@ -1255,7 +1265,7 @@ void IndexIVFFastScan::search_implem_14(
             std::vector<int> q_map(nc), lut_entries(nc);
             AlignedTable<uint8_t> LUT(nc * dim12);
             memset(LUT.get(), -1, nc * dim12);
-            int qbs_2 = pq4_preferred_qbs(nc);
+            int qbs_for_list = pq4_preferred_qbs(nc);
 
             for (size_t i = i0; i < i1; i++) {
                 const QC& qc = qcs[i];
@@ -1268,7 +1278,11 @@ void IndexIVFFastScan::search_implem_14(
                 }
             }
             pq4_pack_LUT_qbs_q_map(
-                    qbs_2, M2, dis_tables.get(), lut_entries.data(), LUT.get());
+                    qbs_for_list,
+                    M2,
+                    dis_tables.get(),
+                    lut_entries.data(),
+                    LUT.get());
 
             // access the inverted list
 
@@ -1284,7 +1298,7 @@ void IndexIVFFastScan::search_implem_14(
             handler->id_map = ids.get();
 
             pq4_accumulate_loop_qbs(
-                    qbs_2,
+                    qbs_for_list,
                     list_size,
                     M2,
                     codes.get(),
diff --git a/faiss/impl/NSG.cpp b/faiss/impl/NSG.cpp
index 32ade32b71..8a6aaf9d90 100644
--- a/faiss/impl/NSG.cpp
+++ b/faiss/impl/NSG.cpp
@@ -301,8 +301,8 @@ void NSG::search_on_graph(
             retset[k].flag = false;
             int n = retset[k].id;
 
-            size_t nneigh_2 = graph.get_neighbors(n, neighbors.data());
-            for (int m = 0; m < nneigh_2; m++) {
+            size_t nneigh_for_n = graph.get_neighbors(n, neighbors.data());
+            for (int m = 0; m < nneigh_for_n; m++) {
                 int id = neighbors[m];
                 if (id > ntotal || vt.get(id)) {
                     continue;