On Thursday, 19 July 2018 at 11:35:00 UTC, Seb wrote:
On Thursday, 19 July 2018 at 10:27:36 UTC, Zheng (Vic) Luo
wrote:
Current implementation of d-runtime relies on a lot of symbols
from libc, librt, libpthread, which makes it hard to create a
minimal runtime used for embedded devices. Although there are
some unofficial minimal versions of d-runtime, many of them
lack maintenance and outdates rapidly. I was wondering that is
there any plan for a https://doc.rust-lang.org/core/ library
in D world, which only depends several explicitly-defined
symbols?
Well, since 2.079 it's actually possible to use D without a
dependency any runtime (even libc):
https://dlang.org/changelog/2.079.0.html#minimal_runtime
Also with -betterC you can actually use lots of things from
core that don't depend on the runtime. For example,
std.algorithm/range works in betterC:
https://run.dlang.io/is/38yowj
Now, I assume you are asking whether there are plans for a
minimal -betterC runtime?
There aren't "official" plans, but AFAICT a few people are
independently working on this. It might be a good idea to join
efforts with them.
Just tried something similar with new LDC Webassembly support [1]
and it fails to compile
---
int foo()
{
import std.algorithm, std.range;
auto r = 100.iota.stride(2).take(5);
return r.sum();
}
---
ldc2 -mtriple=wasm32-unknown-unknown-wasm -betterC
-link-internally -L-allow-undefined -release -Os wasm.d
ldc\bin\..\import\core\stdc\stdio.d(31): Error: module
`core.stdc.stdint` import intptr_t not found
ldc\bin\..\import\core\stdc\stdio.d(1149): Error: undefined
identifier FILE
....
This is a prime example of stuff that should just workTM on
targets like that. I would like to submit some fixes but I think
there needs to be a more systematic approach on making more core
APIs modular.
Also, CI support to make sure core API compile on such targets
and there are no regressions. Webassembly would be an excellent
target as it is both constrained and portable.
1 - https://wiki.dlang.org/Generating_WebAssembly_with_LDC
