xfsprogs for-next branch build failure

[Eryu Guan <eguan@redhat.com>]

Hi all,

I'm seeing a xfsprogs for-next branch (HEAD is f77f9908851e) build
failure in my test.

This build failure only happens if I installed 4.12-rc kernel headers,
which has /usr/include/linux/fsmap.h installed, so that in
xfsprogs/include/builddefs it has "HAVE_GETFSMAP = yes" defined.

e.g. install Fedora rawhide kernel package and its kernel header files,
and re-compile xfsprogs.
kernel-4.12.0-0.rc6.git3.1.fc27.x86_64
kernel-headers-4.12.0-0.rc6.git3.1.fc27.x86_64

Build failure log:

...
Building fsck
Building growfs
...
Building io
...
    [CC]     fsmap.o
In file included from ../include/xfs.h:68:0,
                 from io.h:19,   
                 from fsmap.c:24:
fsmap.c: In function ‘special_owner’:
../include/xfs/xfs_fs.h:117:26: error: ‘FMR_OWN_FREE’ undeclared (first use in this function)
 #define XFS_FMR_OWN_FREE FMR_OWN_FREE      /* free space */
                          ^
fsmap.c:61:7: note: in expansion of macro ‘XFS_FMR_OWN_FREE’
  case XFS_FMR_OWN_FREE:
       ^
../include/xfs/xfs_fs.h:117:26: note: each undeclared identifier is reported only once for each function it appears in
 #define XFS_FMR_OWN_FREE FMR_OWN_FREE      /* free space */
                          ^
fsmap.c:61:7: note: in expansion of macro ‘XFS_FMR_OWN_FREE’
  case XFS_FMR_OWN_FREE:
       ^
../include/xfs/xfs_fs.h:118:29: error: ‘FMR_OWN_UNKNOWN’ undeclared (first use in this function)
 #define XFS_FMR_OWN_UNKNOWN FMR_OWN_UNKNOWN   /* unknown owner */
                             ^
fsmap.c:63:7: note: in expansion of macro ‘XFS_FMR_OWN_UNKNOWN’
  case XFS_FMR_OWN_UNKNOWN:
       ^
fsmap.c:65:2: warning: implicit declaration of function ‘FMR_OWNER’ [-Wimplicit-function-declaration]
  case XFS_FMR_OWN_FS:
  ^
...

Thanks,
Eryu