diff --git a/apps/codecs/libspeex/filters.c b/apps/codecs/libspeex/filters.c
index aaffa9441f..44addc2406 100644
--- a/apps/codecs/libspeex/filters.c
+++ b/apps/codecs/libspeex/filters.c
@@ -606,7 +606,7 @@ const float shift_filt[3][7] = {{-0.011915f, 0.046995f, -0.152373f, 0.614108f, 0
 #endif
 #endif
 
-int interp_pitch(
+static int interp_pitch(
 spx_word16_t *exc,          /*decoded excitation*/
 spx_word16_t *interp,          /*decoded excitation*/
 int pitch,               /*pitch period*/