Thread overview
[[bad mustMatch:]]: error while compiling to wasm
Jul 07
Seb
Jul 07
kinke
Jul 09
kinke
July 07
Hi I was trying to build wasm code via ldc and binaryen. I saw how to do it in a c++ tutorial.

My source code is:

import std.stdio;

extern(C) int main()
{
	writeln("Edit source/app.d to start your project.");
  return 0;
}


I compile with the following:
ldc2 app.d -output-s
s2wasm app.s > app.wast

While compiling to s, everyhing is fine but s2wasm it gives this error:
<< set >>
[[bad mustMatch:]]:
==========
_main:
	.cfi_startproc
	pushq	%rbp
Lcfi0:
	.cfi_def_cfa_offs
==========

It is something related to the D structure? How can I fix this?

Thanks
July 07
On Saturday, 7 July 2018 at 07:55:59 UTC, Hüseyin Akbaş wrote:
> Hi I was trying to build wasm code via ldc and binaryen. I saw how to do it in a c++ tutorial.
>
> My source code is:
>
> import std.stdio;
>
> extern(C) int main()
> {
> 	writeln("Edit source/app.d to start your project.");
>   return 0;
> }
>
>
> I compile with the following:
> ldc2 app.d -output-s
> s2wasm app.s > app.wast
>
> While compiling to s, everyhing is fine but s2wasm it gives this error:
> << set >>
> [[bad mustMatch:]]:
> ==========
> _main:
> 	.cfi_startproc
> 	pushq	%rbp
> Lcfi0:
> 	.cfi_def_cfa_offs
> ==========
>
> It is something related to the D structure? How can I fix this?
>
> Thanks

Did you try -betterC? IIRC the full druntime doesn't work with wasm yet.
July 07
On Saturday, 7 July 2018 at 07:55:59 UTC, Hüseyin Akbaş wrote:
> Hi I was trying to build wasm code via ldc and binaryen. I saw how to do it in a c++ tutorial.
>
> My source code is:
>
> import std.stdio;
>
> extern(C) int main()
> {
> 	writeln("Edit source/app.d to start your project.");
>   return 0;
> }
>
>
> I compile with the following:
> ldc2 app.d -output-s
> s2wasm app.s > app.wast

LDC will soon be able to compile & link some trivial D code directly to WebAssembly, without any external tools. Don't expect a seamingly simple `writeln()` to work soon though [you don't even have access to the console in WebAssembly and must interop with a JavaScript function to do so AFAIK].
See https://github.com/ldc-developers/ldc/pull/2766#issuecomment-403222908 for how to get started.
July 08
On Saturday, 7 July 2018 at 18:01:46 UTC, kinke wrote:
> On Saturday, 7 July 2018 at 07:55:59 UTC, Hüseyin Akbaş wrote:
>> Hi I was trying to build wasm code via ldc and binaryen. I saw how to do it in a c++ tutorial.
>>
>> My source code is:
>>
>> import std.stdio;
>>
>> extern(C) int main()
>> {
>> 	writeln("Edit source/app.d to start your project.");
>>   return 0;
>> }
>>
>>
>> I compile with the following:
>> ldc2 app.d -output-s
>> s2wasm app.s > app.wast
>
> LDC will soon be able to compile & link some trivial D code directly to WebAssembly, without any external tools. Don't expect a seamingly simple `writeln()` to work soon though [you don't even have access to the console in WebAssembly and must interop with a JavaScript function to do so AFAIK].
> See https://github.com/ldc-developers/ldc/pull/2766#issuecomment-403222908 for how to get started.

Some guy has created a toolchain like emscripten in order to compile a few libraries for webasm  with the D code. However, I couldn't make it work. Here is the link: https://github.com/CyberShadow/dscripten-tools What do you think? Is it useful?


July 09
On Sunday, 8 July 2018 at 09:01:09 UTC, Hüseyin Akbaş wrote:
> Some guy has created a toolchain like emscripten in order to compile a few libraries for webasm  with the D code. However, I couldn't make it work. Here is the link: https://github.com/CyberShadow/dscripten-tools What do you think? Is it useful?

I had a quick look.
dscripten compiles to asm.js, a JavaScript subset auto-generated from code in statically typed languages and which most modern JS engines are supposed to generate efficient code for.
'Compiling' to JavaScript isn't supported by official LLVM and seems to require changes to LLVM itself, not just an additional LLVM target, hence it isn't supported by LDC either, and that why there's the dscripten fork using emscripten's LLVM.

WebAssembly is an official LLVM target and AFAICT supposed to replace the ugly and inefficient asm.js layer (that's still source code after all, human-readable for masochists). The first version apparently doesn't give you access to the JS garbage collector or the DOM though. Even passing strings between JS and WebAssembly seems to be a PITA (never seen that much code needed to print a 'hello world' to a console [1]).
DOM and GC access is planned for WebAssembly v2 AFAIK, and only then things start getting interesting IMO, allowing for front-ends fully written in D or interoperating with other JS/WebAssembly libs.

[1] https://medium.com/@mbebenita/hello-world-in-webassembly-83951757775