Appending works better with strings when applied to compile_flags.
Appending works better with strings when applied to compile_flags.

NicolasSchnitzler/dtk,d-tk/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk,rdebroiz/dtk,rdebroiz/dtk,d-tk/dtk,d-tk/dtk,NicolasSchnitzler/dtk,rdebroiz/dtk,NicolasSchnitzler/dtk,d-tk/dtk,d-tk/dtk,d-tk/dtk