Merge branch 'gcc-c90' into refs/top-bases/gcc-branch

diff --cc cmd/zdb/zdb.c
Simple merge

diff --cc module/zfs/arc.c
Simple merge

diff --cc module/zfs/dbuf.c
Simple merge

diff --cc module/zfs/dsl_dataset.c
Simple merge

diff --cc module/zfs/dsl_pool.c
Simple merge

diff --cc module/zfs/sa.c
Simple merge

diff --cc module/zfs/spa.c
Simple merge

diff --cc module/zfs/spa_misc.c
Simple merge

diff --cc module/zfs/vdev.c
Simple merge

diff --cc module/zfs/vdev_label.c
Simple merge

diff --cc module/zfs/zio.c
Simple merge