diff --git a/ccan/ccan/json_out/json_out.c b/ccan/ccan/json_out/json_out.c
index 53837e67c33a..5f497df63bdd 100644
--- a/ccan/ccan/json_out/json_out.c
+++ b/ccan/ccan/json_out/json_out.c
@@ -9,7 +9,7 @@ struct json_out {
 	/* Callback if we reallocate. */
 	void (*move_cb)(struct json_out *jout, ptrdiff_t delta, void *arg);
 	void *cb_arg;
-	
+
 #ifdef CCAN_JSON_OUT_DEBUG
 	/* tal_arr of types ( or [ we're enclosed in.  NULL if oom. */
 	char *wrapping;
@@ -246,7 +246,7 @@ bool json_out_addv(struct json_out *jout,
 		dst = mkroom(jout, fmtlen + 1 + (int)quote*2);
 		if (!dst)
 			goto out;
-		vsprintf(dst + quote, fmt, ap2);
+		vsnprintf(dst + quote, fmtlen + 1, fmt, ap2);
 	}
 
 #ifdef CCAN_JSON_OUT_DEBUG
diff --git a/common/test/run-trace.c b/common/test/run-trace.c
index 7811f68c91dd..e257d445a6d5 100644
--- a/common/test/run-trace.c
+++ b/common/test/run-trace.c
@@ -8,7 +8,7 @@
 int main(int argx, char *argv[])
 {
 	/* Just some context objects to hang spans off of. */
-	int a, b, c, d;
+	int a = 0, b = 0, c = 0, d = 0;
 
 	common_setup(argv[0]);
 
diff --git a/devtools/mkquery.c b/devtools/mkquery.c
index 9fe6e69f858c..d75075121f81 100644
--- a/devtools/mkquery.c
+++ b/devtools/mkquery.c
@@ -17,7 +17,7 @@ int main(int argc, char *argv[])
 {
 	struct bitcoin_blkid chainhash;
 	const tal_t *ctx = tal(NULL, char);
-	const u8 *msg;
+	const u8 *msg = NULL;
 
 	setup_locale();
 	secp256k1_ctx = secp256k1_context_create(SECP256K1_CONTEXT_VERIFY |
@@ -36,7 +36,7 @@ int main(int argc, char *argv[])
 						     strtol(argv[3], NULL, 0),
 						     strtol(argv[4], NULL, 0));
 	} else if (streq(argv[1], "query_channel_range")) {
-		struct tlv_query_channel_range_tlvs *tlvs;
+		struct tlv_query_channel_range_tlvs *tlvs = NULL;
 		if (argc == 5)
 			tlvs = NULL;
 		else if (argc == 6) {
@@ -50,7 +50,7 @@ int main(int argc, char *argv[])
 						 strtol(argv[4], NULL, 0),
 						 tlvs);
 	} else if (streq(argv[1], "query_short_channel_ids")) {
-		struct tlv_query_short_channel_ids_tlvs *tlvs;
+		struct tlv_query_short_channel_ids_tlvs *tlvs = NULL;
 		u8 *encoded;
 
 		if (argc == 4)
diff --git a/lightningd/dual_open_control.c b/lightningd/dual_open_control.c
index 388ba47e748d..42eac1c17589 100644
--- a/lightningd/dual_open_control.c
+++ b/lightningd/dual_open_control.c
@@ -2254,7 +2254,7 @@ static bool verify_option_will_fund_signature(struct peer *peer,
 static void handle_validate_lease(struct subd *dualopend,
 				  const u8 *msg)
 {
-	const secp256k1_ecdsa_signature sig;
+	secp256k1_ecdsa_signature sig = {{0}};
 	u16 chan_fee_max_ppt;
 	u32 chan_fee_max_base_msat, lease_expiry;
 	struct pubkey their_pubkey;
diff --git a/openingd/dualopend.c b/openingd/dualopend.c
index f03f1b927b1d..2b3ff44bf8e2 100644
--- a/openingd/dualopend.c
+++ b/openingd/dualopend.c
@@ -2794,7 +2794,6 @@ static u8 *opener_commits(struct state *state,
 			  struct amount_sat total,
 			  char **err_reason)
 {
-	struct channel_id cid;
 	struct amount_msat our_msats;
 	struct penalty_base *pbase;
 	struct bitcoin_tx *local_commit;
@@ -2853,7 +2852,7 @@ static u8 *opener_commits(struct state *state,
 
 	tal_free(state->channel);
 	state->channel = new_initial_channel(state,
-					     &cid,
+					     &state->channel_id,
 					     &tx_state->funding,
 					     state->minimum_depth,
 					     take(new_height_states(NULL, LOCAL,