diff --git a/Source/cmFileLockUnix.cxx b/Source/cmFileLockUnix.cxx
index fc18a64da..36a2d7288 100644
--- a/Source/cmFileLockUnix.cxx
+++ b/Source/cmFileLockUnix.cxx
@@ -15,6 +15,7 @@
 #include <errno.h> // errno
 #include <stdio.h> // SEEK_SET
 #include <fcntl.h>
+#include <unistd.h>
 #include "cmSystemTools.h"
 
 cmFileLock::cmFileLock(): File(-1)
@@ -31,6 +32,9 @@ cmFileLockResult cmFileLock::Release()
 
   this->Filename = "";
 
+  ::close(this->File);
+  this->File = -1;
+
   if (lockResult == 0)
     {
     return cmFileLockResult::MakeOk();
diff --git a/Source/cmFileLockWin32.cxx b/Source/cmFileLockWin32.cxx
index 469168985..dc65948bd 100644
--- a/Source/cmFileLockWin32.cxx
+++ b/Source/cmFileLockWin32.cxx
@@ -38,6 +38,9 @@ cmFileLockResult cmFileLock::Release()
 
   this->Filename = "";
 
+  CloseHandle(this->File);
+  this->File = INVALID_HANDLE_VALUE;
+
   if (unlockResult)
     {
     return cmFileLockResult::MakeOk();