diff --git a/libtransmission/torrent.c b/libtransmission/torrent.c
index 522f664a7..4ecf360f0 100644
--- a/libtransmission/torrent.c
+++ b/libtransmission/torrent.c
@@ -2808,8 +2808,8 @@ tr_torrentDeleteLocalData( tr_torrent * tor, tr_fileFunc fileFunc )
 struct LocationData
 {
     tr_bool move_from_old_location;
-    int * setme_state;
-    double * setme_progress;
+    volatile int * setme_state;
+    volatile double * setme_progress;
     char * location;
     tr_torrent * tor;
 };
@@ -2905,11 +2905,11 @@ setLocation( void * vdata )
 }
 
 void
-tr_torrentSetLocation( tr_torrent  * tor,
-                       const char  * location,
-                       tr_bool       move_from_old_location,
-                       double      * setme_progress,
-                       int         * setme_state )
+tr_torrentSetLocation( tr_torrent       * tor,
+                       const char       * location,
+                       tr_bool             move_from_old_location,
+                       volatile double  * setme_progress,
+                       volatile int     * setme_state )
 {
     struct LocationData * data;
 
diff --git a/libtransmission/transmission.h b/libtransmission/transmission.h
index 4f8f54186..1095cef60 100644
--- a/libtransmission/transmission.h
+++ b/libtransmission/transmission.h
@@ -1068,11 +1068,11 @@ enum
  * will be clobberred s.t. additional files being added will be saved
  * to the torrent's downloadDir.
  */
-void tr_torrentSetLocation( tr_torrent  * torrent,
-                            const char  * location,
-                            tr_bool       move_from_previous_location,
-                            double      * setme_progress,
-                            int         * setme_state );
+void tr_torrentSetLocation( tr_torrent       * torrent,
+                            const char       * location,
+                            tr_bool            move_from_previous_location,
+                            volatile double  * setme_progress,
+                            volatile int     * setme_state );
 
 uint64_t tr_torrentGetBytesLeftToAllocate( const tr_torrent * torrent );