common: use WARN_UNUSED macro

src/decode.h

@@ -920,7 +920,7 @@ int DecodeSll(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint3
 int DecodePPP(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t);
 int DecodePPPOESession(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t);
 int DecodePPPOEDiscovery(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t);
-int DecodeTunnel(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t, enum DecodeTunnelProto) __attribute__ ((warn_unused_result));
+int DecodeTunnel(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t, enum DecodeTunnelProto) WARN_UNUSED;
 int DecodeNull(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t);
 int DecodeRaw(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint32_t);
 int DecodeIPV4(ThreadVars *, DecodeThreadVars *, Packet *, const uint8_t *, uint16_t);

src/util-streaming-buffer.c

@@ -442,7 +442,7 @@ static void AutoSlide(StreamingBuffer *sb)
     SBBPrune(sb);
 }
 
-static int __attribute__((warn_unused_result))
+static int WARN_UNUSED
 GrowToSize(StreamingBuffer *sb, uint32_t size)
 {
     /* try to grow in multiples of sb->cfg->buf_size */
@@ -476,7 +476,7 @@ GrowToSize(StreamingBuffer *sb, uint32_t size)
  *  \retval 0 ok
  *  \retval -1 failed, buffer unchanged
  */
-static int __attribute__((warn_unused_result)) Grow(StreamingBuffer *sb)
+static int WARN_UNUSED Grow(StreamingBuffer *sb)
 {
     uint32_t grow = sb->buf_size * 2;
     void *ptr = REALLOC(sb->cfg, sb->buf, sb->buf_size, grow);

src/util-streaming-buffer.h

@@ -126,14 +126,14 @@ void StreamingBufferSlide(StreamingBuffer *sb, uint32_t slide);
 void StreamingBufferSlideToOffset(StreamingBuffer *sb, uint64_t offset);
 
 StreamingBufferSegment *StreamingBufferAppendRaw(StreamingBuffer *sb,
-        const uint8_t *data, uint32_t data_len) __attribute__((warn_unused_result));
+        const uint8_t *data, uint32_t data_len) WARN_UNUSED;
 int StreamingBufferAppend(StreamingBuffer *sb, StreamingBufferSegment *seg,
-        const uint8_t *data, uint32_t data_len) __attribute__((warn_unused_result));
+        const uint8_t *data, uint32_t data_len) WARN_UNUSED;
 int StreamingBufferAppendNoTrack(StreamingBuffer *sb,
-        const uint8_t *data, uint32_t data_len) __attribute__((warn_unused_result));
+        const uint8_t *data, uint32_t data_len) WARN_UNUSED;
 int StreamingBufferInsertAt(StreamingBuffer *sb, StreamingBufferSegment *seg,
                              const uint8_t *data, uint32_t data_len,
-                             uint64_t offset) __attribute__((warn_unused_result));
+                             uint64_t offset) WARN_UNUSED;
 
 void StreamingBufferSegmentGetData(const StreamingBuffer *sb,
                                    const StreamingBufferSegment *seg,