diff --git a/zfs/lib/libzfs/libzfs_dataset.c b/zfs/lib/libzfs/libzfs_dataset.c
index 63399f208c..3f49652abb 100644
--- a/zfs/lib/libzfs/libzfs_dataset.c
+++ b/zfs/lib/libzfs/libzfs_dataset.c
@@ -1104,7 +1104,7 @@ zfs_build_perms(zfs_handle_t *zhp, char *whostr, char *perms,
 	nvlist_t *perms_nvp = NULL;
 	nvlist_t *sets_nvp = NULL;
 	char errbuf[1024];
-	char *who_tok, *perm;
+	char *who_tok = NULL, *perm;
 	int error;
 
 	*nvp = NULL;
@@ -3639,7 +3639,7 @@ zfs_rollback(zfs_handle_t *zhp, zfs_handle_t *snap, boolean_t force)
 	int err;
 	zfs_cmd_t zc = { 0 };
 	boolean_t restore_resv = 0;
-	uint64_t old_volsize, new_volsize;
+	uint64_t old_volsize = 0, new_volsize;
 	zfs_prop_t resv_prop;
 
 	assert(zhp->zfs_type == ZFS_TYPE_FILESYSTEM ||
@@ -3890,6 +3890,7 @@ zfs_rename(zfs_handle_t *zhp, const char *target, boolean_t recursive)
 			    "child dataset with inherited mountpoint is used "
 			    "in a non-global zone"));
 			(void) zfs_error(hdl, EZFS_ZONED, errbuf);
+			ret = -1;
 			goto error;
 		}
 
diff --git a/zfs/lib/libzpool/arc.c b/zfs/lib/libzpool/arc.c
index 7fe24cfe54..059eb3aa01 100644
--- a/zfs/lib/libzpool/arc.c
+++ b/zfs/lib/libzpool/arc.c
@@ -2453,7 +2453,7 @@ arc_read_nolock(zio_t *pio, spa_t *spa, blkptr_t *bp,
     uint32_t *arc_flags, const zbookmark_t *zb)
 {
 	arc_buf_hdr_t *hdr;
-	arc_buf_t *buf;
+	arc_buf_t *buf = NULL;
 	kmutex_t *hash_lock;
 	zio_t *rzio;
 
@@ -2836,7 +2836,7 @@ arc_release(arc_buf_t *buf, void *tag)
 	arc_buf_hdr_t *hdr;
 	kmutex_t *hash_lock;
 	l2arc_buf_hdr_t *l2hdr;
-	uint64_t buf_size;
+	uint64_t buf_size = 0;
 
 	rw_enter(&buf->b_lock, RW_WRITER);
 	hdr = buf->b_hdr;
@@ -3879,7 +3879,7 @@ l2arc_read_done(zio_t *zio)
 static list_t *
 l2arc_list_locked(int list_num, kmutex_t **lock)
 {
-	list_t *list;
+	list_t *list = NULL;
 
 	ASSERT(list_num >= 0 && list_num <= 3);
 
@@ -4052,10 +4052,11 @@ l2arc_write_buffers(spa_t *spa, l2arc_dev_t *dev, uint64_t target_sz)
 	list_t *list;
 	uint64_t passed_sz, write_sz, buf_sz, headroom;
 	void *buf_data;
-	kmutex_t *hash_lock, *list_lock;
+	kmutex_t *hash_lock, *list_lock = NULL;
 	boolean_t have_lock, full;
 	l2arc_write_callback_t *cb;
 	zio_t *pio, *wzio;
+	int try;
 
 	ASSERT(dev->l2ad_vdev != NULL);
 
diff --git a/zfs/lib/libzpool/dsl_dataset.c b/zfs/lib/libzpool/dsl_dataset.c
index fefbf8f5fa..169e824df5 100644
--- a/zfs/lib/libzpool/dsl_dataset.c
+++ b/zfs/lib/libzpool/dsl_dataset.c
@@ -353,7 +353,7 @@ dsl_dataset_get_ref(dsl_pool_t *dp, uint64_t dsobj, void *tag,
 		return (err);
 	ds = dmu_buf_get_user(dbuf);
 	if (ds == NULL) {
-		dsl_dataset_t *winner;
+		dsl_dataset_t *winner = NULL;
 
 		ds = kmem_zalloc(sizeof (dsl_dataset_t), KM_SLEEP);
 		ds->ds_dbuf = dbuf;
diff --git a/zfs/lib/libzpool/lzjb.c b/zfs/lib/libzpool/lzjb.c
index 7fcde8475e..4132406bd6 100644
--- a/zfs/lib/libzpool/lzjb.c
+++ b/zfs/lib/libzpool/lzjb.c
@@ -51,7 +51,7 @@ lzjb_compress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
 {
 	uchar_t *src = s_start;
 	uchar_t *dst = d_start;
-	uchar_t *cpy, *copymap;
+	uchar_t *cpy, *copymap = NULL;
 	int copymask = 1 << (NBBY - 1);
 	int mlen, offset;
 	uint16_t *hp;
@@ -104,7 +104,7 @@ lzjb_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n)
 	uchar_t *src = s_start;
 	uchar_t *dst = d_start;
 	uchar_t *d_end = (uchar_t *)d_start + d_len;
-	uchar_t *cpy, copymap;
+	uchar_t *cpy, copymap = 0;
 	int copymask = 1 << (NBBY - 1);
 
 	while (dst < d_end) {
diff --git a/zfs/lib/libzpool/refcount.c b/zfs/lib/libzpool/refcount.c
index 2a52cb16da..2ce8e43568 100644
--- a/zfs/lib/libzpool/refcount.c
+++ b/zfs/lib/libzpool/refcount.c
@@ -113,7 +113,7 @@ refcount_count(refcount_t *rc)
 int64_t
 refcount_add_many(refcount_t *rc, uint64_t number, void *holder)
 {
-	reference_t *ref;
+	reference_t *ref = NULL;
 	int64_t count;
 
 	if (reference_tracking_enable) {
diff --git a/zfs/lib/libzpool/spa.c b/zfs/lib/libzpool/spa.c
index bc5ba5336f..bd4ce35b28 100644
--- a/zfs/lib/libzpool/spa.c
+++ b/zfs/lib/libzpool/spa.c
@@ -274,7 +274,7 @@ spa_prop_validate(spa_t *spa, nvlist_t *props)
 {
 	nvpair_t *elem;
 	int error = 0, reset_bootfs = 0;
-	uint64_t objnum;
+	uint64_t objnum = 0;
 
 	elem = NULL;
 	while ((elem = nvlist_next_nvpair(props, elem)) != NULL) {
@@ -819,7 +819,7 @@ spa_load_l2cache(spa_t *spa)
 	uint_t nl2cache;
 	int i, j, oldnvdevs;
 	uint64_t guid, size;
-	vdev_t *vd, **oldvdevs, **newvdevs;
+	vdev_t *vd, **oldvdevs, **newvdevs = NULL;
 	spa_aux_vdev_t *sav = &spa->spa_l2cache;
 
 	ASSERT(spa_config_held(spa, SCL_ALL, RW_WRITER) == SCL_ALL);
@@ -3008,7 +3008,7 @@ spa_vdev_detach(spa_t *spa, uint64_t guid, int replace_done)
 	vdev_t *rvd = spa->spa_root_vdev;
 	vdev_t *vd, *pvd, *cvd, *tvd;
 	boolean_t unspare = B_FALSE;
-	uint64_t unspare_guid;
+	uint64_t unspare_guid = 0;
 	size_t len;
 
 	txg = spa_vdev_enter(spa);
diff --git a/zfs/lib/libzpool/vdev_raidz.c b/zfs/lib/libzpool/vdev_raidz.c
index 69e314468e..33e7f102c3 100644
--- a/zfs/lib/libzpool/vdev_raidz.c
+++ b/zfs/lib/libzpool/vdev_raidz.c
@@ -789,7 +789,7 @@ vdev_raidz_io_done(zio_t *zio)
 	vdev_t *vd = zio->io_vd;
 	vdev_t *cvd;
 	raidz_map_t *rm = zio->io_vsd;
-	raidz_col_t *rc, *rc1;
+	raidz_col_t *rc = NULL, *rc1;
 	int unexpected_errors = 0;
 	int parity_errors = 0;
 	int parity_untried = 0;
diff --git a/zfs/lib/libzpool/zap_leaf.c b/zfs/lib/libzpool/zap_leaf.c
index da498b6bc9..267f296fb3 100644
--- a/zfs/lib/libzpool/zap_leaf.c
+++ b/zfs/lib/libzpool/zap_leaf.c
@@ -220,7 +220,7 @@ zap_leaf_array_create(zap_leaf_t *l, const char *buf,
 	uint16_t chunk_head;
 	uint16_t *chunkp = &chunk_head;
 	int byten = 0;
-	uint64_t value;
+	uint64_t value = 0;
 	int shift = (integer_size-1)*8;
 	int len = num_integers;
 
diff --git a/zfs/lib/libzpool/zfs_byteswap.c b/zfs/lib/libzpool/zfs_byteswap.c
index ab97f83eb0..177ff552c0 100644
--- a/zfs/lib/libzpool/zfs_byteswap.c
+++ b/zfs/lib/libzpool/zfs_byteswap.c
@@ -52,7 +52,7 @@ zfs_ace_byteswap(void *buf, size_t size, boolean_t zfs_layout)
 {
 	caddr_t end;
 	caddr_t ptr;
-	zfs_ace_t *zacep;
+	zfs_ace_t *zacep = NULL;
 	ace_t *acep;
 	uint16_t entry_type;
 	size_t entry_size;