diff --git a/faiss/gpu/utils/MergeNetworkWarp.cuh b/faiss/gpu/utils/MergeNetworkWarp.cuh
index 39b3008..06d0c91 100644
--- a/faiss/gpu/utils/MergeNetworkWarp.cuh
+++ b/faiss/gpu/utils/MergeNetworkWarp.cuh
@@ -13,6 +13,10 @@
 #include <faiss/gpu/utils/PtxUtils.cuh>
 #include <faiss/gpu/utils/WarpShuffles.cuh>
 
+#ifdef small
+#undef small
+#endif
+
 namespace faiss {
 namespace gpu {
 
