From: Jan Beulich <jbeulich@suse.com>
To: "Roger Pau Monné" <roger.pau@citrix.com>
Cc: xen-devel@lists.xenproject.org,
Doug Goldstein <cardoe@cardoe.com>,
Stefano Stabellini <sstabellini@kernel.org>,
Ian Jackson <iwj@xenproject.org>,
Andrew Cooper <andrew.cooper3@citrix.com>
Subject: Re: [PATCH for-4.15] automation/alpine: add g++ to the list of build depends
Date: Tue, 2 Mar 2021 10:54:23 +0100 [thread overview]
Message-ID: <77e7004f-8a73-e868-1ccd-318de5886f4a@suse.com> (raw)
In-Reply-To: <YD4HM9+IEZKIq/SQ@Air-de-Roger>
On 02.03.2021 10:36, Roger Pau Monné wrote:
> On Tue, Mar 02, 2021 at 09:53:41AM +0100, Jan Beulich wrote:
>> On 02.03.2021 09:14, Roger Pau Monné wrote:
>>> On Mon, Mar 01, 2021 at 06:01:36PM +0000, Andrew Cooper wrote:
>>>> On 01/03/2021 17:59, Andrew Cooper wrote:
>>>>> On 01/03/2021 09:58, Roger Pau Monne wrote:
>>>>>> clang++ relies on the C++ headers installed by g++, or else a clang
>>>>>> build will hit the following error:
>>>>>>
>>>>>> <built-in>:3:10: fatal error: 'cstring' file not found
>>>>>> #include "cstring"
>>>>>> ^~~~~~~~~
>>>>>> 1 error generated.
>>>>>> make[10]: *** [Makefile:120: headers++.chk] Error 1
>>>>>>
>>>>>> Reported-by: Stefano Stabellini <sstabellini@kernel.org>
>>>>>> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
>>>>>> ---
>>>>>> Cc: Ian Jackson <iwj@xenproject.org>
>>>>>> No real risk here from a release PoV, it's just pulling a package
>>>>>> required for the Alpine clang build. Worse that cold happen is that
>>>>>> the Alpine clang build broke, but it's already broken.
>>>>> Shouldn't this be fixed upstream in Alpine? Its clearly a packaging bug.
>>>>
>>>> Or (thinking about it), we've got a build system bug using g++ when it
>>>> should be using clang++.
>>>
>>> No, the check is using clang++, the issue is that clang++ doesn't
>>> install the standard c++ headers, and thus trying to use them (cstring
>>> in this case) fails. Installing the g++ package solves the issue
>>> because it installs the headers.
>>
>> I have to admit that I consider this odd. The g++ package should
>> neither provide nor depend on the headers. It may recommend their
>> installation. On my distro (SLES) the headers come from the
>> libstdc++-devel package, as I would have expected. There
>> additionally is a dependency of libclang5 (no -devel suffix!) on
>> libstdc++-devel (I suppose this is an indication that things
>> aren't quite right here either; I haven't checked an up-to-date
>> version of the distro yet, though).
>
> Yes, that was indeed my first attempt as I've tried to install
> libstdc++, but there's no -devel counterpart for the package, and it
> only installs the libraries but not the headers.
>
> Then if I list the contents of the g++ package, I do see:
>
> ...
> usr/include/c++/10.2.1/cstring
> ...
>
> And clang++'s include path is:
>
> #include <...> search starts here:
> /usr/bin/../lib/gcc/x86_64-alpine-linux-musl/10.2.1/../../../../include/c++/10.2.1
> /usr/bin/../lib/gcc/x86_64-alpine-linux-musl/10.2.1/../../../../include/c++/10.2.1/x86_64-alpine-linux-musl
> /usr/bin/../lib/gcc/x86_64-alpine-linux-musl/10.2.1/../../../../include/c++/10.2.1/backward
> /usr/include
> /usr/lib/clang/10.0.1/include
>
> So it does seem clang depends on the gcc c++ headers, I assume this is
> done in order to avoid having a duplicate set of c++ headers for clang
> and gcc? I really have no idea, but I do think clang package should
> depend on g++.
As long as the g++ package is what provides the headers (i.e. if that's
their concept), I agree.
Jan
next prev parent reply other threads:[~2021-03-02 9:54 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-01 9:58 [PATCH for-4.15] automation/alpine: add g++ to the list of build depends Roger Pau Monne
2021-03-01 17:20 ` Ian Jackson
2021-03-01 17:59 ` Andrew Cooper
2021-03-01 18:01 ` Andrew Cooper
2021-03-02 8:14 ` Roger Pau Monné
2021-03-02 8:53 ` Jan Beulich
2021-03-02 9:36 ` Roger Pau Monné
2021-03-02 9:54 ` Jan Beulich [this message]
2021-03-02 19:39 ` Stefano Stabellini
2021-03-06 1:40 ` Stefano Stabellini
2021-03-06 9:22 ` Roger Pau Monné
-- strict thread matches above, loose matches on Subject: below --
2021-03-01 9:57 Roger Pau Monne
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=77e7004f-8a73-e868-1ccd-318de5886f4a@suse.com \
--to=jbeulich@suse.com \
--cc=andrew.cooper3@citrix.com \
--cc=cardoe@cardoe.com \
--cc=iwj@xenproject.org \
--cc=roger.pau@citrix.com \
--cc=sstabellini@kernel.org \
--cc=xen-devel@lists.xenproject.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).