diff --git a/clang/lib/ASTMatchers/Dynamic/Registry.cpp b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
index df4f29d0f0a9..8948d18e8f0f 100644
--- a/clang/lib/ASTMatchers/Dynamic/Registry.cpp
+++ b/clang/lib/ASTMatchers/Dynamic/Registry.cpp
@@ -185,6 +185,7 @@ RegistryMaps::RegistryMaps() {
   REGISTER_MATCHER(functionProtoType);
   REGISTER_MATCHER(functionTemplateDecl);
   REGISTER_MATCHER(functionType);
+  REGISTER_MATCHER(gnuNullExpr);
   REGISTER_MATCHER(gotoStmt);
   REGISTER_MATCHER(has);
   REGISTER_MATCHER(hasAncestor);