C API / const char *text / std.string.toStringz pointer is always NULL on C side

[rikki cattermole]

On 17/05/2018 3:07 AM, Robert M. Münch wrote:
> I have an extern(C) function in a DLL with this signature:
> 
> result* myfunc(double x, double y, const char *text, stuff *myStuff, 
> bool flag);
> 
> I call it like this:
> 
> result = myfunc(0, 0, std.string.toStringz("1"), stuff, true);
> 
> 
> The problem is, that on the DLL side *text is always NULL. I doesn't 
> matter what I put as third argument. And even more strange, I have an 
> other function with a const char* as first argument. There everything is 
> working...
> 
> Any idea what cause this could be? This is really strange...

Please post the C function prototype.