Hopefully fixed. These fcntl() calls are supposed to be portable, but I can only test on linux here. Please let me know if something is still not working.

Just for the record, the {0} initializer warnings is a compiler bug.

commit 4e239a6632ca648e3bf39b120e2d15822e5540e4
Author: George Kiagiadakis <george.kiagiadakis@collabora.com>
Date:   Thu Aug 31 15:07:45 2017 +0300

    examples: ipcpipeline: do not use the linux-specific SOCK_NONBLOCK flag
    
    Use fcntl() instead to set O_NONBLOCK, which is portable.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786763

commit 282b682caba2fc3d932591d7842cb953ad2357f8
Author: George Kiagiadakis <george.kiagiadakis@collabora.com>
Date:   Thu Aug 31 14:57:34 2017 +0300

    tests: ipcpipeline: provide pipe2() on systems that don't have it
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786763

(In reply to George Kiagiadakis from comment #1) 
> Just for the record, the {0} initializer warnings is a compiler bug.

I'm not sure it make sense in this context, but I've seen code initializing the first member of the struct with proper type, and then just adding a comma, which was assumed more portable in the code I've seen.

  struct my_type mt = { NULL, };

make -C tests/examples/ipcpipeline/
  CC       ipcpipeline1-ipcpipeline1.o
  CCLD     ipcpipeline1
  CC       ipc_play-ipc-play.o
ipc-play.c:972:42: error: use of undeclared identifier 'SOCK_NONBLOCK'
  if (socketpair (AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0, pipes)) {
                                         ^
1 error generated.
make: *** [ipc_play-ipc-play.o] Error 1

Also, I wonder why ipcpipeline is in DIST_SUBDIRS but not in SUBDIRS in the Makefile.am. Is that intended?

commit 91edec25dd2a50e44b970296e55e1570c3e0d33c
Author: George Kiagiadakis <george.kiagiadakis@collabora.com>
Date:   Mon Sep 4 10:39:58 2017 +0300

    examples: ipcpipeline: get rid of yet another use of SOCK_NONBLOCK
    
    https://bugzilla.gnome.org/show_bug.cgi?id=786763

(In reply to Philippe Normand from comment #4)
> Also, I wonder why ipcpipeline is in DIST_SUBDIRS but not in SUBDIRS in the
> Makefile.am. Is that intended?

No specific intention, I just followed the example of others. I'm not sure if there's a policy for SUBDIRS vs DIST_SUBDIRS usage?

It is in SUBDIRS when enabled:

if USE_IPCPIPELINE
IPCPIPELINE_DIR=ipcpipeline
else
IPCPIPELINE_DIR=
endif

SUBDIRS = ... $(IPCPIPELINE_DIR) ...


(It's more efficient to prevent make descending into subdirs if the whole plugin is disabled)

(In reply to Tim-Philipp Müller from comment #7)
> It is in SUBDIRS when enabled:
> 
> if USE_IPCPIPELINE
> IPCPIPELINE_DIR=ipcpipeline
> else
> IPCPIPELINE_DIR=
> endif
> 
> SUBDIRS = ... $(IPCPIPELINE_DIR) ...

I believe Philippe is talking about tests/examples/Makefile.am

(In reply to George Kiagiadakis from comment #8)
> I believe Philippe is talking about tests/examples/Makefile.am

Oh! And looking at your reply, I just realized I should have done the same trick for tests/examples/Makefile.am

Will fix.