2 files changed, 3 insertions, 2 deletions
diff --git a/fonttosfnt.h b/fonttosfnt.h
index 53d9587..63852c5 100644
--- a/fonttosfnt.h
+++ b/fonttosfnt.h
@@ -161,7 +161,7 @@ FontPtr makeFont(void);
 StrikePtr makeStrike(FontPtr, int, int);
 BitmapPtr makeBitmap(StrikePtr, int,
                      int, int, int, int, int, int,
-                     unsigned char*, int);
+                     const unsigned char*, int);
 IndexSubTablePtr makeIndexSubTables(StrikePtr, CmapPtr);
 int fontIndex(FontPtr, int);
 CmapPtr makeCmap(FontPtr);
diff --git a/struct.c b/struct.c
index a44b1e8..2463180 100644
--- a/struct.c
+++ b/struct.c
@@ -112,7 +112,8 @@ makeStrike(FontPtr font, int sizeX, int sizeY)
 BitmapPtr
 makeBitmap(StrikePtr strike, int code,
            int advanceWidth, int horiBearingX, int horiBearingY,
-           int width, int height, int stride, unsigned char *raster, int crop)
+           int width, int height, int stride,
+           const unsigned char *raster, int crop)
 {
     BitmapPtr bitmap;
     int i, j, x, y;