diff --git a/triplets/x64-linux-mixed.cmake b/triplets/x64-linux-mixed.cmake
index 7e70894..94a3404 100644
--- a/triplets/x64-linux-mixed.cmake
+++ b/triplets/x64-linux-mixed.cmake
@@ -11,7 +11,6 @@ endif()
 
 if(PORT MATCHES "libsystemd")
     set(VCPKG_C_FLAGS "-std=c11")
-    set(VCPKG_CXX_FLAGS "-std=c11")
 endif()
 
 if(PORT MATCHES "opus")