include: add some LIBVLC_USED flag.

include/vlc_block_helper.h

@@ -37,6 +37,7 @@ typedef struct block_bytestream_t
 /*****************************************************************************
  * block_bytestream_t management
  *****************************************************************************/
+LIBVLC_USED
 static inline block_bytestream_t block_BytestreamInit( void )
 {
     block_bytestream_t bytestream;

include/vlc_codec.h

@@ -178,7 +178,7 @@ struct encoder_t
  * buffer. You have to release it using decoder_DeletePicture or by returning
  * it to the caller as a pf_decode_video return value.
  */
-VLC_EXPORT( picture_t *, decoder_NewPicture, ( decoder_t * ) );
+VLC_EXPORT( picture_t *, decoder_NewPicture, ( decoder_t * ) LIBVLC_USED );
 
 /**
  * This function will release a picture create by decoder_NewPicture.
@@ -202,7 +202,7 @@ VLC_EXPORT( void, decoder_UnlinkPicture, ( decoder_t *, picture_t * ) );
  * output buffer. You have to release it using decoder_DeleteAudioBuffer
  * or by returning it to the caller as a pf_decode_audio return value.
  */
-VLC_EXPORT( aout_buffer_t *, decoder_NewAudioBuffer, ( decoder_t *, int i_size ) );
+VLC_EXPORT( aout_buffer_t *, decoder_NewAudioBuffer, ( decoder_t *, int i_size ) LIBVLC_USED );
 
 /**
  * This function will release a audio buffer created by decoder_NewAudioBuffer.
@@ -214,7 +214,7 @@ VLC_EXPORT( void, decoder_DeleteAudioBuffer, ( decoder_t *, aout_buffer_t *p_buf
  * buffer. You have to release it using decoder_DeleteSubpicture or by returning
  * it to the caller as a pf_decode_sub return value.
  */
-VLC_EXPORT( subpicture_t *, decoder_NewSubpicture, ( decoder_t * ) );
+VLC_EXPORT( subpicture_t *, decoder_NewSubpicture, ( decoder_t * ) LIBVLC_USED );
 
 /**
  * This function will release a subpicture created by decoder_NewSubicture.
@@ -239,6 +239,6 @@ VLC_EXPORT( mtime_t, decoder_GetDisplayDate, ( decoder_t *, mtime_t ) LIBVLC_USE
  * This function returns the current input rate.
  * You MUST use it *only* for gathering statistics about speed.
  */
-VLC_EXPORT( int, decoder_GetDisplayRate, ( decoder_t * ) );
+VLC_EXPORT( int, decoder_GetDisplayRate, ( decoder_t * ) LIBVLC_USED );
 
 #endif /* _VLC_CODEC_H */