ENH: coverage cleanup for non XCode builds

CTestCustom.ctest.in

@@ -22,3 +22,11 @@ SET(CTEST_CUSTOM_WARNING_EXCEPTION
   )
 
 
+IF(NOT "@CMAKE_GENERATOR@" MATCHES "XCode")
+  SET(CTEST_CUSTOM_COVERAGE_EXCLUDE
+    ${CTEST_CUSTOM_COVERAGE_EXCLUDE}
+    "XCode"
+    )
+ENDIF (NOT "@CMAKE_GENERATOR@" MATCHES "XCode")
+  
+