diff --git a/src/libImaging/Bcn.h b/src/libImaging/Bcn.h
index 743c5d121..f142df9f3 100644
--- a/src/libImaging/Bcn.h
+++ b/src/libImaging/Bcn.h
@@ -28,5 +28,3 @@ typedef struct {
     INT8 a0, a1;
     UINT8 lut[6];
 } bc5s_alpha;
-
-rgba decode_565(UINT16 x);
\ No newline at end of file
diff --git a/src/libImaging/BcnDecode.c b/src/libImaging/BcnDecode.c
index 9163d8335..69c317815 100644
--- a/src/libImaging/BcnDecode.c
+++ b/src/libImaging/BcnDecode.c
@@ -28,7 +28,7 @@ bc1_color_load(bc1_color *dst, const UINT8 *src) {
     dst->lut = LOAD32(src + 4);
 }
 
-rgba
+static rgba
 decode_565(UINT16 x) {
     rgba c;
     int r, g, b;