diff --git a/gobject/tests/qdata.c b/gobject/tests/qdata.c
index 528bdc68e..7d46efb15 100644
--- a/gobject/tests/qdata.c
+++ b/gobject/tests/qdata.c
@@ -17,7 +17,7 @@ gboolean fail;
 #define ROUNDS 10000
 
 GObject *object;
-volatile gint bucket[THREADS];
+gint bucket[THREADS];  /* accessed from multiple threads, but should never be contested due to the sequence of thread operations */
 
 static gpointer
 thread_func (gpointer data)
diff --git a/gobject/tests/threadtests.c b/gobject/tests/threadtests.c
index e341a9d67..b6f9e17fa 100644
--- a/gobject/tests/threadtests.c
+++ b/gobject/tests/threadtests.c
@@ -27,8 +27,8 @@
 #include <glib.h>
 #include <glib-object.h>
 
-static volatile int mtsafe_call_counter = 0; /* multi thread safe call counter */
-static int          unsafe_call_counter = 0; /* single-threaded call counter */
+static int mtsafe_call_counter = 0; /* multi thread safe call counter, must be accessed atomically */
+static int unsafe_call_counter = 0; /* single-threaded call counter */
 static GCond sync_cond;
 static GMutex sync_mutex;