diff --git a/demos/demo_imi_pq.cpp b/demos/demo_imi_pq.cpp
index a2af65e792..4fab0778d8 100644
--- a/demos/demo_imi_pq.cpp
+++ b/demos/demo_imi_pq.cpp
@@ -77,7 +77,6 @@ int main() {
     // the coarse quantizer should not be dealloced before the index
     // 4 = nb of bytes per code (d must be a multiple of this)
     // 8 = nb of bits per sub-code (almost always 8)
-    faiss::MetricType metric = faiss::METRIC_L2; // can be METRIC_INNER_PRODUCT
     faiss::IndexIVFPQ index(
             &coarse_quantizer, d, ncentroids, bytes_per_code, 8);
     index.quantizer_trains_alone = true;
diff --git a/faiss/IndexIVF.cpp b/faiss/IndexIVF.cpp
index 95d3bc9e68..548aaa4cc7 100644
--- a/faiss/IndexIVF.cpp
+++ b/faiss/IndexIVF.cpp
@@ -444,7 +444,7 @@ void IndexIVF::search_preassigned(
         max_codes = unlimited_list_size;
     }
 
-    bool do_parallel = omp_get_max_threads() >= 2 &&
+    [[maybe_unused]] bool do_parallel = omp_get_max_threads() >= 2 &&
             (pmode == 0           ? false
                      : pmode == 3 ? n > 1
                      : pmode == 1 ? nprobe > 1
@@ -784,7 +784,7 @@ void IndexIVF::range_search_preassigned(
 
     int pmode = this->parallel_mode & ~PARALLEL_MODE_NO_HEAP_INIT;
     // don't start parallel section if single query
-    bool do_parallel = omp_get_max_threads() >= 2 &&
+    [[maybe_unused]] bool do_parallel = omp_get_max_threads() >= 2 &&
             (pmode == 3           ? false
                      : pmode == 0 ? nx > 1
                      : pmode == 1 ? nprobe > 1
diff --git a/faiss/utils/distances.cpp b/faiss/utils/distances.cpp
index 82bc164ae1..74b56bcc87 100644
--- a/faiss/utils/distances.cpp
+++ b/faiss/utils/distances.cpp
@@ -141,7 +141,7 @@ void exhaustive_inner_product_seq(
         const IDSelector* sel = nullptr) {
     using SingleResultHandler =
             typename BlockResultHandler::SingleResultHandler;
-    int nt = std::min(int(nx), omp_get_max_threads());
+    [[maybe_unused]] int nt = std::min(int(nx), omp_get_max_threads());
 
     FAISS_ASSERT(use_sel == (sel != nullptr));
 
@@ -178,7 +178,7 @@ void exhaustive_L2sqr_seq(
         const IDSelector* sel = nullptr) {
     using SingleResultHandler =
             typename BlockResultHandler::SingleResultHandler;
-    int nt = std::min(int(nx), omp_get_max_threads());
+    [[maybe_unused]] int nt = std::min(int(nx), omp_get_max_threads());
 
     FAISS_ASSERT(use_sel == (sel != nullptr));