Don't use the -fvisibility switch if the visibility attributes didn't work

CMakeLists.txt

@@ -181,6 +181,7 @@ IF(WIN32)
     ENDIF()
 ELSE()
     SET(OLD_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
+    # Yes GCC, really don't accept visibility modes you don't support
     SET(CMAKE_REQUIRED_FLAGS "${OLD_REQUIRED_FLAGS} -Werror")
 
     CHECK_C_SOURCE_COMPILES("int foo() __attribute__((visibility(\"protected\")));
@@ -195,13 +196,15 @@ ELSE()
         ENDIF()
     ENDIF()
 
-    CHECK_C_COMPILER_FLAG(-fvisibility=internal HAVE_VISIBILITY_INTERNAL_SWITCH)
-    IF(HAVE_VISIBILITY_INTERNAL_SWITCH)
-        ADD_DEFINITIONS(-fvisibility=internal)
-    ELSE()
-        CHECK_C_COMPILER_FLAG(-fvisibility=hidden HAVE_VISIBILITY_HIDDEN_SWITCH)
-        IF(HAVE_VISIBILITY_HIDDEN_SWITCH)
-            ADD_DEFINITIONS(-fvisibility=hidden)
+    IF(HAVE_GCC_PROTECTED_VISIBILITY OR HAVE_GCC_DEFAULT_VISIBILITY)
+        CHECK_C_COMPILER_FLAG(-fvisibility=internal HAVE_VISIBILITY_INTERNAL_SWITCH)
+        IF(HAVE_VISIBILITY_INTERNAL_SWITCH)
+            ADD_DEFINITIONS(-fvisibility=internal)
+        ELSE()
+            CHECK_C_COMPILER_FLAG(-fvisibility=hidden HAVE_VISIBILITY_HIDDEN_SWITCH)
+            IF(HAVE_VISIBILITY_HIDDEN_SWITCH)
+                ADD_DEFINITIONS(-fvisibility=hidden)
+            ENDIF()
         ENDIF()
     ENDIF()