C++ compilation error on a datatype with a type parameter

[fpoli]

The C++ code generated by the following program doesn't compile.

Command: dafny /compile:3 /spillTargetCode:2 /compileTarget:cpp Program.dfy

Program:

newtype nat32 = i:int | 0 <= i < 0x80000000

datatype PhantomData<T> = PhantomData(value: T)

method Main() {
    var x: nat32 := 123;
    var p := PhantomData(x);
}

Output:

Dafny program verifier finished with 2 verified, 0 errors
Wrote textual form of target program to Comp.cpp
Additional target code written to Comp.h
Comp.cpp:30:34: error: use of undeclared identifier 'T'
    _13_p = _module::PhantomData<T>(_12_x);
                                 ^
1 error generated.
Error while compiling C++ files. Process exited with exit code 1