diff --git a/src/decode-udp.c b/src/decode-udp.c
index 7753e9bbd9..12b093f721 100644
--- a/src/decode-udp.c
+++ b/src/decode-udp.c
@@ -8,126 +8,6 @@
 #include "util-debug.h"
 #include "flow.h"
 
-/**
- * \brief Calculates the checksum for the UDP packet
- *
- * \param shdr Pointer to source address field from the IP packet.  Used as a
- *             part of the psuedoheader for computing the checksum
- * \param pkt  Pointer to the start of the UDP packet
- * \param hlen Total length of the UDP packet(header + payload)
- *
- * \retval csum Checksum for the UDP packet
- */
-inline uint16_t UDPV4CalculateChecksum(uint16_t *shdr, uint16_t *pkt,
-                                       uint16_t tlen)
-{
-    uint16_t pad = 0;
-    uint32_t csum = shdr[0];
-
-    csum += shdr[1] + shdr[2] + shdr[3] + htons(17 + tlen);
-
-    csum += pkt[0] + pkt[1] + pkt[2];
-
-    tlen -= 8;
-    pkt += 4;
-
-    while (tlen >= 32) {
-        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3] + pkt[4] + pkt[5] + pkt[6] +
-            pkt[7] + pkt[8] + pkt[9] + pkt[10] + pkt[11] + pkt[12] + pkt[13] +
-            pkt[14] + pkt[15];
-        tlen -= 32;
-        pkt += 16;
-    }
-
-    while(tlen >= 8) {
-        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3];
-        tlen -= 8;
-        pkt += 4;
-    }
-
-    while(tlen >= 4) {
-        csum += pkt[0] + pkt[1];
-        tlen -= 4;
-        pkt += 2;
-    }
-
-    while (tlen > 1) {
-        csum += pkt[0];
-        pkt += 1;
-        tlen -= 2;
-    }
-
-    if (tlen == 1) {
-        *(uint8_t *)(&pad) = (*(uint8_t *)pkt);
-        csum += pad;
-    }
-
-    csum = (csum >> 16) + (csum & 0x0000FFFF);
-
-    return (uint16_t) ~csum;
-}
-
-/**
- * \brief Calculates the checksum for the UDP packet
- *
- * \param shdr Pointer to source address field from the IPV6 packet.  Used as a
- *             part of the psuedoheader for computing the checksum
- * \param pkt  Pointer to the start of the UDP packet
- * \param tlen Total length of the UDP packet(header + payload)
- *
- * \retval csum Checksum for the UDP packet
- */
-inline uint16_t UDPV6CalculateChecksum(uint16_t *shdr, uint16_t *pkt,
-                                       uint16_t tlen)
-{
-    uint16_t pad = 0;
-    uint32_t csum = shdr[0];
-
-    csum += shdr[1] + shdr[2] + shdr[3] + shdr[4] + shdr[5] + shdr[6] +
-        shdr[7] + shdr[8] + shdr[9] + shdr[10] + shdr[11] + shdr[12] +
-        shdr[13] + shdr[14] + shdr[15] + htons(17 + tlen);
-
-    csum += pkt[0] + pkt[1] + pkt[2];
-
-    tlen -= 8;
-    pkt += 4;
-
-    while (tlen >= 32) {
-        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3] + pkt[4] + pkt[5] + pkt[6] +
-            pkt[7] + pkt[8] + pkt[9] + pkt[10] + pkt[11] + pkt[12] + pkt[13] +
-            pkt[14] + pkt[15];
-        tlen -= 32;
-        pkt += 16;
-    }
-
-    while(tlen >= 8) {
-        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3];
-        tlen -= 8;
-        pkt += 4;
-    }
-
-    while(tlen >= 4) {
-        csum += pkt[0] + pkt[1];
-        tlen -= 4;
-        pkt += 2;
-    }
-
-    while (tlen > 1) {
-        csum += pkt[0];
-        pkt += 1;
-        tlen -= 2;
-    }
-
-    if (tlen == 1) {
-        *(uint8_t *)(&pad) = (*(uint8_t *)pkt);
-        csum += pad;
-    }
-
-    csum = (csum >> 16) + (csum & 0x0000FFFF);
-
-    return (uint16_t) ~csum;
-}
-
 static int DecodeUDPPacket(ThreadVars *t, Packet *p, uint8_t *pkt, uint16_t len)
 {
     if (len < UDP_HEADER_LEN) {
diff --git a/src/decode-udp.h b/src/decode-udp.h
index 691f2f8064..81263e1062 100644
--- a/src/decode-udp.h
+++ b/src/decode-udp.h
@@ -33,8 +33,131 @@ typedef struct UDPCache_ {
     int32_t comp_csum;
 } UDPCache;
 
-inline uint16_t UDPV4CalculateChecksum(uint16_t *, uint16_t *, uint16_t);
-inline uint16_t UDPV6CalculateChecksum(uint16_t *, uint16_t *, uint16_t);
 void DecodeUDPV4RegisterTests(void);
 
+/** ------ Inline function ------ */
+static inline uint16_t UDPV4CalculateChecksum(uint16_t *, uint16_t *, uint16_t);
+static inline uint16_t UDPV6CalculateChecksum(uint16_t *, uint16_t *, uint16_t);
+
+/**
+ * \brief Calculates the checksum for the UDP packet
+ *
+ * \param shdr Pointer to source address field from the IP packet.  Used as a
+ *             part of the psuedoheader for computing the checksum
+ * \param pkt  Pointer to the start of the UDP packet
+ * \param hlen Total length of the UDP packet(header + payload)
+ *
+ * \retval csum Checksum for the UDP packet
+ */
+static inline uint16_t UDPV4CalculateChecksum(uint16_t *shdr, uint16_t *pkt,
+                                       uint16_t tlen)
+{
+    uint16_t pad = 0;
+    uint32_t csum = shdr[0];
+
+    csum += shdr[1] + shdr[2] + shdr[3] + htons(17 + tlen);
+
+    csum += pkt[0] + pkt[1] + pkt[2];
+
+    tlen -= 8;
+    pkt += 4;
+
+    while (tlen >= 32) {
+        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3] + pkt[4] + pkt[5] + pkt[6] +
+            pkt[7] + pkt[8] + pkt[9] + pkt[10] + pkt[11] + pkt[12] + pkt[13] +
+            pkt[14] + pkt[15];
+        tlen -= 32;
+        pkt += 16;
+    }
+
+    while(tlen >= 8) {
+        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3];
+        tlen -= 8;
+        pkt += 4;
+    }
+
+    while(tlen >= 4) {
+        csum += pkt[0] + pkt[1];
+        tlen -= 4;
+        pkt += 2;
+    }
+
+    while (tlen > 1) {
+        csum += pkt[0];
+        pkt += 1;
+        tlen -= 2;
+    }
+
+    if (tlen == 1) {
+        *(uint8_t *)(&pad) = (*(uint8_t *)pkt);
+        csum += pad;
+    }
+
+    csum = (csum >> 16) + (csum & 0x0000FFFF);
+
+    return (uint16_t) ~csum;
+}
+
+/**
+ * \brief Calculates the checksum for the UDP packet
+ *
+ * \param shdr Pointer to source address field from the IPV6 packet.  Used as a
+ *             part of the psuedoheader for computing the checksum
+ * \param pkt  Pointer to the start of the UDP packet
+ * \param tlen Total length of the UDP packet(header + payload)
+ *
+ * \retval csum Checksum for the UDP packet
+ */
+static inline uint16_t UDPV6CalculateChecksum(uint16_t *shdr, uint16_t *pkt,
+                                       uint16_t tlen)
+{
+    uint16_t pad = 0;
+    uint32_t csum = shdr[0];
+
+    csum += shdr[1] + shdr[2] + shdr[3] + shdr[4] + shdr[5] + shdr[6] +
+        shdr[7] + shdr[8] + shdr[9] + shdr[10] + shdr[11] + shdr[12] +
+        shdr[13] + shdr[14] + shdr[15] + htons(17 + tlen);
+
+    csum += pkt[0] + pkt[1] + pkt[2];
+
+    tlen -= 8;
+    pkt += 4;
+
+    while (tlen >= 32) {
+        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3] + pkt[4] + pkt[5] + pkt[6] +
+            pkt[7] + pkt[8] + pkt[9] + pkt[10] + pkt[11] + pkt[12] + pkt[13] +
+            pkt[14] + pkt[15];
+        tlen -= 32;
+        pkt += 16;
+    }
+
+    while(tlen >= 8) {
+        csum += pkt[0] + pkt[1] + pkt[2] + pkt[3];
+        tlen -= 8;
+        pkt += 4;
+    }
+
+    while(tlen >= 4) {
+        csum += pkt[0] + pkt[1];
+        tlen -= 4;
+        pkt += 2;
+    }
+
+    while (tlen > 1) {
+        csum += pkt[0];
+        pkt += 1;
+        tlen -= 2;
+    }
+
+    if (tlen == 1) {
+        *(uint8_t *)(&pad) = (*(uint8_t *)pkt);
+        csum += pad;
+    }
+
+    csum = (csum >> 16) + (csum & 0x0000FFFF);
+
+    return (uint16_t) ~csum;
+}
+
+
 #endif /* __DECODE_UDP_H__ */