diff --git a/tools/hcidump.c b/tools/hcidump.c
index f19466d..f424028 100644
--- a/tools/hcidump.c
+++ b/tools/hcidump.c
@@ -532,7 +532,8 @@ static int wait_connection(in_addr_t addr, in_port_t port)
 {
 	struct sockaddr_in sa;
 	struct hostent *host;
-	int sk, nsk, opt, len;
+	socklen_t len;
+	int sk, nsk, opt;
 
 	sk = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 	if (sk < 0) {
@@ -564,7 +565,8 @@ static int wait_connection(in_addr_t addr, in_port_t port)
 	}
 
 	len = sizeof(sa);
-	if ((nsk = accept(sk, (struct sockaddr *) &sa, &len)) < 0) {
+	nsk = accept(sk, (struct sockaddr *) &sa, &len);
+	if (nsk < 0) {
 		perror("Can't accept new inet socket");
 		close(sk);
 		exit(1);
diff --git a/tools/parser/avdtp.c b/tools/parser/avdtp.c
index 4d93fa6..aa1003b 100644
--- a/tools/parser/avdtp.c
+++ b/tools/parser/avdtp.c
@@ -143,9 +143,8 @@ static char *codec2str(uint8_t type, uint8_t codec)
 			return "Reserved";
 		}
 		break;
-	default:
-		return "Unknown";
 	}
+	return "Unknown";
 }
 
 static char *cat2str(uint8_t cat)
diff --git a/tools/parser/capi.c b/tools/parser/capi.c
index a625fb9..1e26365 100644
--- a/tools/parser/capi.c
+++ b/tools/parser/capi.c
@@ -764,7 +764,7 @@ static void cmd_manufacturer(int level, uint8_t subcmd, struct frame *frm)
 	frm->ptr += 4;
 	frm->len -= 4;
 
-	if (!strncmp(id, "AVM!", 4)) {
+	if (!strncmp((char *) id, "AVM!", 4)) {
 		class = CAPI_U32(frm);
 		func = CAPI_U32(frm);
 		len = CAPI_U8(frm);
diff --git a/tools/parser/sdp.c b/tools/parser/sdp.c
index 3232402..3f0f5c5 100644
--- a/tools/parser/sdp.c
+++ b/tools/parser/sdp.c
@@ -360,7 +360,7 @@ static inline void print_des(uint8_t de_type, int level, int n, struct frame *fr
 
 static inline void print_de(int level, struct frame *frm, int *split, uint16_t *psm, uint8_t *channel)
 {
-	int n;
+	int n = 0;
 	uint8_t de_type = parse_de_hdr(frm, &n);
 
 	switch (de_type) {
@@ -471,7 +471,7 @@ static inline void print_attr_list(int level, struct frame *frm)
 {
 	uint16_t attr_id, psm;
 	uint8_t channel;
-	int len, n1, n2, split;
+	int len, split, n1 = 0, n2 = 0;
 
 	if (parse_de_hdr(frm, &n1) == SDP_DE_SEQ) {
 		len = frm->len;