https://bugs.gentoo.org/721988

--- a/ttaenc.c
+++ b/ttaenc.c
@@ -525,7 +525,7 @@ __inline void memshl (register int *pA, register int *pB) {
 	*pA   = *pB;
 }
 
-__inline void hybrid_filter (fltst *fs, int *in, int mode) {
+static void hybrid_filter (fltst *fs, int *in, int mode) {
 	register int *pA = fs->dl;
 	register int *pB = fs->qm;
 	register int *pM = fs->dx;