diff --git a/stb_image.h b/stb_image.h
index 55edc3e5389f608c8fbbc82f747840156122c19b..67d29810ebdf4390b13a13c03505678a97323206 100644
--- a/stb_image.h
+++ b/stb_image.h
@@ -3544,7 +3544,7 @@ static void stbi__fill_bits(stbi__zbuf *z)
 {
    do {
       STBI_ASSERT(z->code_buffer < (1U << z->num_bits));
-      z->code_buffer |= stbi__zget8(z) << z->num_bits;
+      z->code_buffer |= (usigned int) stbi__zget8(z) << z->num_bits;
       z->num_bits += 8;
    } while (z->num_bits <= 24);
 }
diff --git a/stb_vorbis.c b/stb_vorbis.c
index 8a549d66cfc110ae618c8810c0c8a3984fc9daa1..98e96fb98db73cfb78adee45a91dbc170d700f7f 100644
--- a/stb_vorbis.c
+++ b/stb_vorbis.c
@@ -1293,7 +1293,7 @@ static uint32 get32(vorb *f)
    x = get8(f);
    x += get8(f) << 8;
    x += get8(f) << 16;
-   x += get8(f) << 24;
+   x += (uint32) get8(f) << 24;
    return x;
 }