diff --git a/test/function_n_test.cpp b/test/function_n_test.cpp
index 48fefc3..7fcf3f2 100644
--- a/test/function_n_test.cpp
+++ b/test/function_n_test.cpp
@@ -7,8 +7,10 @@
 
 // For more information, see http://www.boost.org
 
-#if defined(__clang__)
-# pragma clang diagnostic ignored "-Wself-assign-overloaded"
+#if defined(__clang__) && defined(__has_warning)
+# if __has_warning( "-Wself-assign-overloaded" )
+#  pragma clang diagnostic ignored "-Wself-assign-overloaded"
+# endif
 #endif
 
 #include <boost/function.hpp>
diff --git a/test/function_test.cpp b/test/function_test.cpp
index f6b7301..7592837 100644
--- a/test/function_test.cpp
+++ b/test/function_test.cpp
@@ -7,8 +7,10 @@
 
 // For more information, see http://www.boost.org
 
-#if defined(__clang__)
-# pragma clang diagnostic ignored "-Wself-assign-overloaded"
+#if defined(__clang__) && defined(__has_warning)
+# if __has_warning( "-Wself-assign-overloaded" )
+#  pragma clang diagnostic ignored "-Wself-assign-overloaded"
+# endif
 #endif
 
 #include <boost/function.hpp>
diff --git a/test/mem_fun_cxx98.cpp b/test/mem_fun_cxx98.cpp
index 9274036..b42cc00 100644
--- a/test/mem_fun_cxx98.cpp
+++ b/test/mem_fun_cxx98.cpp
@@ -16,7 +16,7 @@
 
 struct Y {
     Y(int y = 0) : y_(y) {}
-    bool operator==(const Y& rhs) { return y_ == rhs.y_; }
+    bool operator==(const Y& rhs) const { return y_ == rhs.y_; }
 private:
     int y_;
     };
diff --git a/test/mem_fun_portable.cpp b/test/mem_fun_portable.cpp
index e12fd08..0cf1ed4 100644
--- a/test/mem_fun_portable.cpp
+++ b/test/mem_fun_portable.cpp
@@ -16,7 +16,7 @@
 
 struct Y {
     Y(int y = 0) : y_(y) {}
-    bool operator==(const Y& rhs) { return y_ == rhs.y_; }
+    bool operator==(const Y& rhs) const { return y_ == rhs.y_; }
 private:
     int y_;
     };