compile D to asm.js using ldc --betterC and emcc

[SrMordred]

On Sunday, 8 October 2017 at 09:48:57 UTC, Dukc wrote:
> On Saturday, 7 October 2017 at 17:31:37 UTC, cosinus wrote:
>> I wrote a little working demo that shows how to use D inside 
>> firefox.
>>
>> It uses emscripten(emcc) and ldc.
>>
>> https://github.com/cosinus2/dlang-emscripten-demo
>
> Judging by looking at that build script, sure that's simpler 
> than what I read you had to do some time back! You had to 
> switch to some legacy llvm and compile the indermediate first 
> to C and only then to Asm.js.
>
> This looks like powerful enough for normal use. You still miss 
> DRuntime but a lot better than using C to do the same. Perhaps 
> even better than Typescript in some cases?

Can someone explain the reasons why LDC can't compiles to webasm 
with the DRuntime?