Ah yes, those are part of the "it just works" philosophy of Futhark. Unlike c2nim and nimterop you're not supposed to edit neither the code going in, nor the code coming out. To facilitate this Futhark adds these guard statements. You can disable them with `-d:nodeclguards` at the risk of the wrapper maybe breaking. To rename things you can also register a `renameCallback` which is called for each identifier and allows you to apply any naming scheme you like without the hassle of post processing.
C++ support is also planned, just haven't gotten around to it yet.