diff --git a/src/PlumedFile.cpp b/src/PlumedFile.cpp
index 14083755a051bd29a44aa7c05deb65c62dd3f34a..175f0d9ac4428d0c2216d7523d202dc674b4b896 100644
--- a/src/PlumedFile.cpp
+++ b/src/PlumedFile.cpp
@@ -142,7 +142,7 @@ PlumedFileBase::PlumedFileBase():
 
 PlumedFileBase::~PlumedFileBase()
 {
-  if(!cloned) fclose(fp);
+  if(!cloned && fp) fclose(fp);
 }
 
 PlumedFileBase::operator bool()const{