DMARC-Filter: OpenDMARC Filter v1.4.2 delorie.com 53K5STKB130924
Authentication-Results: delorie.com; dmarc=pass (p=none dis=none) header.from=cygwin.com
Authentication-Results: delorie.com; spf=pass smtp.mailfrom=cygwin.com
DKIM-Filter: OpenDKIM Filter v2.11.0 delorie.com 53K5STKB130924
Authentication-Results: delorie.com;
	dkim=pass (1024-bit key, unprotected) header.d=cygwin.com header.i=@cygwin.com header.a=rsa-sha256 header.s=default header.b=SkxzdKCh
X-Recipient: archive-cygwin AT delorie DOT com
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org F35CA3858D3C
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1745126907;
	bh=xQjzHmS0NNXTb68YQOqm3H3hd6lVN3/MIS0aZPvx1Uo=;
	h=Date:To:cc:Subject:In-Reply-To:References:List-Id:
	 List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe:
	 From:Reply-To:From;
	b=SkxzdKChSPSPN85muZuY0z+PaS4I27a7SUxyFZRDLaeTJothEGINF9iXBBGm5e8Eh
	 +ZIhCxSsrKHKhBaw9hGP4Bt64ItpT6CjD1/m2KpL82nLlrZNm5P9iqTsXsUAWlonU5
	 BFyhTjRwDQbVLQAZcUnBB4nq+Vr9eg4SaKPyTsng=
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org E92413858D37
ARC-Filter: OpenARC Filter v1.0.0 sourceware.org E92413858D37
ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1745126839; cv=none;
 b=uSgyNoavCiAWmakUhhn6H8Fsos4ODRUY54rmlGXN+2C9TxmzXBxgZ6aiXpe3sjRlQaggTUBf3IYsdLFMn68GQ+/xO6zV1f3LQW/QscOUZBZwMTfP66l2q5s8XChJd+/RPAebujaEZHFPataSVaBYxiBR3FFbE/iZ0C3AToLhLSU=
ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key;
 t=1745126839; c=relaxed/simple;
 bh=qI0UOi80lx3pheQ6Gi89cUQb+JKljIDzq+CXf7uZSKY=;
 h=DKIM-Signature:Date:From:To:Subject:Message-ID:MIME-Version;
 b=FDZhJ5iS+r0y2uICLoZGgV/T7RBvKHhX8sB3crrYe+feBr2PUYcSSZeumwTpwvij4Ihr73PpTV6rpWllKoILx95oyRc1oOkSrXqgJEwRZBvCqdMGYdCdDPeS3ssgFBsFknEJLnvXACdX8QMDX33zvpmadYdP5abzZrgx/gicZs4=
ARC-Authentication-Results: i=1; server2.sourceware.org
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E92413858D37
Date: Sat, 19 Apr 2025 22:27:18 -0700 (PDT)
X-X-Sender: jeremyd AT resin DOT csoft DOT net
To: Takashi Yano <takashi DOT yano AT nifty DOT ne DOT jp>
cc: cygwin AT cygwin DOT com, Yuyi Wang <Strawberry_Str AT hotmail DOT com>,
        oss AT mateuszmikula DOT dev
Subject: Re: Rust for cygwin (was Re: Deadlock when calling pthread_key_create
 in the destructor of a pthread_key)
In-Reply-To: <20250420132359.bfd51ddf860f3faaf518b378@nifty.ne.jp>
Message-ID: <d0c31bfd-3086-9190-a610-9bbf9cea659a@jdrake.com>
References: <20250324145221 DOT 25188bbb53d8ee7a8160e3ab AT nifty DOT ne DOT jp>
 <TYCPR01MB10926E7778CD9FFFD49F126EEF8A42 AT TYCPR01MB10926 DOT jpnprd01 DOT prod DOT outlook DOT com>
 <20250420132359 DOT bfd51ddf860f3faaf518b378 AT nifty DOT ne DOT jp>
MIME-Version: 1.0
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.30
Precedence: list
List-Id: General Cygwin discussions and problem reports <cygwin.cygwin.com>
List-Unsubscribe: <https://cygwin.com/mailman/options/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=unsubscribe>
List-Archive: <https://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <https://cygwin.com/mailman/listinfo/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From: Jeremy Drake via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Jeremy Drake <cygwin AT jdrake DOT com>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Errors-To: cygwin-bounces~archive-cygwin=delorie DOT com AT cygwin DOT com
Sender: "Cygwin" <cygwin-bounces~archive-cygwin=delorie DOT com AT cygwin DOT com>

On Sun, 20 Apr 2025, Takashi Yano via Cygwin wrote:

> On Mon, 24 Mar 2025 14:41:19 +0800
> Yuyi Wang wrote:
> > > I mean it is some kind of cross compiler.
> >
> > Yes. Rustc is a cross compiler powered by LLVM.
> >
> > > ...is it possible to build Rust compiler itself by the cross-compiler?
> >
> > Theoretically yes. Actually once a GitHub user @Ookiineko succeeded before, but
> > now the account has been deleted. I think the largest blocker is LLVM itself.
> > The latest version of LLVM provided by cygwin is 8.0, and 11.0 by MSYS2, while
> > rustc needs LLVM 17.0 at least. @Ookiineko added some patches to LLVM to make it
> > work, but they were not committed to upstream, but I haven't understand all of
> > them yet.
>
> Thanks to MSYS2 guys' work, I have successfully built LLVM package with Polly,
> Clang, compiler-rt, and libunwind packages version 20.1.2.
> I still trying built libc++ and libc++abi, but it is not going smoothly.
>
> Is there any other blocker to build Rust for cygwin?

The next thing you need is to build rust on a system that already has a
working rust and a working Cygwin (cross-)compiler (gcc) environment, with
support for the Cygwin target enabled.  This could be Linux, or
technically could be a cross-compile from Windows to Cygwin (in which case
the "Cygwin cross-compiler" is really the normal Cygwin GCC being run by
Windows processes).  Once you've got that built, you would use that rust
to build a rust whose host *and* target are Cygwin.  I don't expect that
to go without issues, trying to get {i686,aarch64}-pc-windows-gnullvm
bootstrapped was a bit of a hassle of patching vendored crates because
it's surprising how many of them knew about targets, and it's rather a
nightmare how many different versions of crates are involved sometimes,
and how long you have to wait for fixes to percolate through the
ecosystem.  Rust also will default to trying to build its own vendored
version of LLVM, so you might end up having to patch that too (or tell
Rust to use the system LLVM instead and save that step).


-- 
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple