diff --git a/util/env_posix.cc b/util/env_posix.cc
index d84cd1e..e6a5743 100644
--- a/util/env_posix.cc
+++ b/util/env_posix.cc
@@ -108,7 +108,7 @@ class Limiter {
 class PosixSequentialFile final : public SequentialFile {
  public:
   PosixSequentialFile(std::string filename, int fd)
-      : fd_(fd), filename_(filename) {}
+      : fd_(fd), filename_(std::move(filename)) {}
   ~PosixSequentialFile() override { close(fd_); }
 
   Status Read(size_t n, Slice* result, char* scratch) override {