diff --git a/indra/llrender/llrender.cpp b/indra/llrender/llrender.cpp
index df7ac879f77990b781ae662cc474d5b0077ebd7f..322507c6530f9a707fd51429fac6c94684c4b44d 100644
--- a/indra/llrender/llrender.cpp
+++ b/indra/llrender/llrender.cpp
@@ -83,7 +83,7 @@ struct LLVBCache
     std::chrono::steady_clock::time_point touched;
 };
 
-static boost::unordered_flat_map<U64, LLVBCache> sVBCache;
+static boost::unordered_map<U64, LLVBCache> sVBCache;
 
 static const GLenum sGLTextureType[] =
 {