Date: Wed, 8 Mar 2017 11:25:07 -0500
From: Rich Felker <dalias@aerifal.cx>
To: "Carlos O'Donell" <carlos@redhat.com>
Cc: linux-kernel@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        linux-api@vger.kernel.org, musl@lists.openwall.com
Subject: Re: [musl] Re: [PATCH resent] uapi libc compat: allow non-glibc to
 opt out of uapi definitions
Message-ID: <20170308162507.GY1520@brightrain.aerifal.cx>
References: <20161111120820.GA435@nyan>
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On Wed, Mar 08, 2017 at 10:53:00AM -0500, Carlos O'Donell wrote:
> On 11/11/2016 07:08 AM, Felix Janda wrote:
> > Currently, libc-compat.h detects inclusion of specific glibc headers,
> > and defines corresponding _UAPI_DEF_* macros, which in turn are used in
> > uapi headers to prevent definition of conflicting structures/constants.
> > There is no such detection for other c libraries, for them the
> > _UAPI_DEF_* macros are always defined as 1, and so none of the possibly
> > conflicting definitions are suppressed.
> > 
> > This patch enables non-glibc c libraries to request the suppression of
> > any specific interface by defining the corresponding _UAPI_DEF_* macro
> > as 0.
> > 
> > This patch together with the recent musl libc commit
> > 
> > http://git.musl-libc.org/cgit/musl/commit/?id=04983f2272382af92eb8f8838964ff944fbb8258
> 
> Would it be possible to amend the musl patch to define the macros to 1.

I don't follow. They're defined to 0 explicitly to tell the kernel
headers not to define their own versions of these structs, etc. since
they would clash. Defining to 1 would have the opposite meaning.

Rich