Re: [PATCH] build: Silence clang warning on older glib autoptr usage

[Eric Blake <eblake@redhat.com>]

On 3/17/20 1:11 PM, Peter Maydell wrote:
> On Tue, 17 Mar 2020 at 17:55, Eric Blake <eblake@redhat.com> wrote:
>>
>> glib's G_DEFINE_AUTOPTR_CLEANUP_FUNC() macro defines several static
>> inline functions, often with some of them unused, but prior to 2.57.2
>> did not mark the functions as such.  As a result, clang (but not gcc)
>> fails to build with older glib unless -Wno-unused-function is enabled.
>>
>> Reported-by: Peter Maydell <peter.maydell@linaro.org>
>> Signed-off-by: Eric Blake <eblake@redhat.com>
>> ---
>>
>> Half-tested: I proved to myself that this does NOT enable
>> -Wno-unused-function on my setup of glib 2.62.5 and gcc 9.2.1 (Fedora
>> 31), but would do so if I introduced an intentional compile error into
>> the sample program; but Iwas unable to test that it would prevent the
>> build failure encountered by Peter on John's pull request (older glib
>> but exact version unknown, clang, on NetBSD).
> 
> This wasn't a NetBSD failure. I hit it on my clang-on-x86-64-Ubuntu
> setup, and also on FreeBSD. (The latter is just the tests/vm
> FreeBSD config, so you can repro that if you need to.)

Not sure where I got NetBSD from (maybe because the build failure 
happened in a file with 'nbd' in the name and I gravitated to the 'n'?). 
  But now that I've re-read your replies to the pull request, I'm glad 
to state that my mistake on reproduction platform is confined to the 
part after the ---; the commit message itself is accurate as-is.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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