diff --git a/src/tools/clangbackend/clangbackend.pro b/src/tools/clangbackend/clangbackend.pro
index c3210fedbfb..e1e08c9cb0d 100644
--- a/src/tools/clangbackend/clangbackend.pro
+++ b/src/tools/clangbackend/clangbackend.pro
@@ -16,5 +16,5 @@ SOURCES += clangbackendmain.cpp
 
 unix {
     !osx: QMAKE_LFLAGS += -Wl,-z,origin
-    !disable_external_rpath: QMAKE_LFLAGS += -Wl,-rpath,$$shell_quote($${LLVM_LIBDIR})
+    !contains(QMAKE_DEFAULT_LIBDIRS, $${LLVM_LIBDIR}):!disable_external_rpath: QMAKE_LFLAGS += -Wl,-rpath,$$shell_quote($${LLVM_LIBDIR})
 }