diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
index a547fbb03e67..d61724be8a07 100644
--- a/module/zfs/dbuf.c
+++ b/module/zfs/dbuf.c
@@ -170,11 +170,6 @@ static void dbuf_write(dbuf_dirty_record_t *dr, arc_buf_t *data, dmu_tx_t *tx);
 static void dbuf_sync_leaf_verify_bonus_dnode(dbuf_dirty_record_t *dr);
 static int dbuf_read_verify_dnode_crypt(dmu_buf_impl_t *db, uint32_t flags);
 
-extern inline void dmu_buf_init_user(dmu_buf_user_t *dbu,
-    dmu_buf_evict_func_t *evict_func_sync,
-    dmu_buf_evict_func_t *evict_func_async,
-    dmu_buf_t **clear_on_evict_dbufp);
-
 /*
  * Global data structures and functions for the dbuf cache.
  */
diff --git a/module/zfs/dsl_dataset.c b/module/zfs/dsl_dataset.c
index 4623bcec4ea8..e8692c95438a 100644
--- a/module/zfs/dsl_dataset.c
+++ b/module/zfs/dsl_dataset.c
@@ -90,8 +90,6 @@ int zfs_allow_redacted_dataset_mount = 0;
 
 #define	DS_REF_MAX	(1ULL << 62)
 
-extern inline dsl_dataset_phys_t *dsl_dataset_phys(dsl_dataset_t *ds);
-
 static void dsl_dataset_set_remap_deadlist_object(dsl_dataset_t *ds,
     uint64_t obj, dmu_tx_t *tx);
 static void dsl_dataset_unset_remap_deadlist_object(dsl_dataset_t *ds,
diff --git a/module/zfs/dsl_dir.c b/module/zfs/dsl_dir.c
index e4ff7d8e754f..43ef1897811c 100644
--- a/module/zfs/dsl_dir.c
+++ b/module/zfs/dsl_dir.c
@@ -121,8 +121,6 @@
  * dsl_dir_init_fs_ss_count().
  */
 
-extern inline dsl_dir_phys_t *dsl_dir_phys(dsl_dir_t *dd);
-
 static uint64_t dsl_dir_space_towrite(dsl_dir_t *dd);
 
 typedef struct ddulrt_arg {
diff --git a/module/zfs/zap.c b/module/zfs/zap.c
index 6f03beef3bdb..4cd14287a5a2 100644
--- a/module/zfs/zap.c
+++ b/module/zfs/zap.c
@@ -80,8 +80,6 @@ int zap_iterate_prefetch = B_TRUE;
 
 int fzap_default_block_shift = 14; /* 16k blocksize */
 
-extern inline zap_phys_t *zap_f_phys(zap_t *zap);
-
 static uint64_t zap_allocate_blocks(zap_t *zap, int nblocks);
 
 void
diff --git a/module/zfs/zap_leaf.c b/module/zfs/zap_leaf.c
index aa6c298c3b4b..aad923d512df 100644
--- a/module/zfs/zap_leaf.c
+++ b/module/zfs/zap_leaf.c
@@ -52,8 +52,6 @@ static uint16_t *zap_leaf_rehash_entry(zap_leaf_t *l, uint16_t entry);
 
 #define	LEAF_HASH_ENTPTR(l, h)	(&zap_leaf_phys(l)->l_hash[LEAF_HASH(l, h)])
 
-extern inline zap_leaf_phys_t *zap_leaf_phys(zap_leaf_t *l);
-
 static void
 zap_memset(void *a, int c, size_t n)
 {
diff --git a/module/zfs/zap_micro.c b/module/zfs/zap_micro.c
index b4611685b204..1f32e4450522 100644
--- a/module/zfs/zap_micro.c
+++ b/module/zfs/zap_micro.c
@@ -41,8 +41,6 @@
 #include <sys/sunddi.h>
 #endif
 
-extern inline mzap_phys_t *zap_m_phys(zap_t *zap);
-
 static int mzap_upgrade(zap_t **zapp,
     void *tag, dmu_tx_t *tx, zap_flags_t flags);