diff --git a/src/client/linux/handler/exception_handler_unittest.cc b/src/client/linux/handler/exception_handler_unittest.cc
index 289c9cd1..b4065b41 100644
--- a/src/client/linux/handler/exception_handler_unittest.cc
+++ b/src/client/linux/handler/exception_handler_unittest.cc
@@ -774,8 +774,13 @@ TEST(ExceptionHandlerTest, InstructionPointerMemoryNullPointer) {
                              true, -1);
     // Try calling a NULL pointer.
     typedef void (*void_function)(void);
-    void_function memory_function = reinterpret_cast<void_function>(NULL);
+    // Volatile markings are needed to keep Clang from generating invalid
+    // opcodes.  See http://crbug.com/498354 for details.
+    volatile void_function memory_function =
+      reinterpret_cast<void_function>(NULL);
     memory_function();
+    // not reached
+    exit(1);
   }
   close(fds[1]);
 
diff --git a/src/client/mac/tests/exception_handler_test.cc b/src/client/mac/tests/exception_handler_test.cc
index e19944d0..a8cf6968 100644
--- a/src/client/mac/tests/exception_handler_test.cc
+++ b/src/client/mac/tests/exception_handler_test.cc
@@ -610,7 +610,9 @@ TEST_F(ExceptionHandlerTest, InstructionPointerMemoryNullPointer) {
     ExceptionHandler eh(tempDir.path(), NULL, MDCallback, &fds[1], true, NULL);
     // Try calling a NULL pointer.
     typedef void (*void_function)(void);
-    void_function memory_function =
+    // Volatile markings are needed to keep Clang from generating invalid
+    // opcodes.  See http://crbug.com/498354 for details.
+    volatile void_function memory_function =
       reinterpret_cast<void_function>(NULL);
     memory_function();
     // not reached