diff --git a/src/corelib/CMakeLists.txt b/src/corelib/CMakeLists.txt
index 84423f400f..a1cb450627 100644
--- a/src/corelib/CMakeLists.txt
+++ b/src/corelib/CMakeLists.txt
@@ -550,14 +550,6 @@ qt_internal_extend_target(Core CONDITION WIN32
         tools/qhash.cpp # Q_DECL_INIT_PRIORITY
 )
 
-qt_internal_extend_target(Core CONDITION LINUX
-    NO_UNITY_BUILD_SOURCES
-        # Some of the macros in X11.h and Xlib.h are colliding with
-        # symbols defined in some of the enums, e.g., None.
-        io/qurl.h
-        serialization/qjsonvalue.h
-)
-
 if(NOT WIN32)
     ### Qt7: remove
     # Make qwineventnotifier.h available on non-Windows platforms too for code bases that include