diff --git a/triplets/x64-linux-mixed.cmake b/triplets/x64-linux-mixed.cmake
index 94a3404..64a6feb 100644
--- a/triplets/x64-linux-mixed.cmake
+++ b/triplets/x64-linux-mixed.cmake
@@ -10,7 +10,8 @@ if(PORT MATCHES "discord-")
 endif()
 
 if(PORT MATCHES "libsystemd")
-    set(VCPKG_C_FLAGS "-std=c11")
+    set(VCPKG_C_FLAGS "${VCPKG_C_FLAGS} -std=c11")
+    set(VCPKG_CXX_FLAGS "${VCPKG_CXX_FLAGS}")
 endif()
 
 if(PORT MATCHES "opus")