diff --git a/libc/include/sys/socket.h b/libc/include/sys/socket.h
index 43d1586..ff8a815 100644
--- a/libc/include/sys/socket.h
+++ b/libc/include/sys/socket.h
@@ -109,7 +109,7 @@
 
 #define CMSG_NXTHDR(mhdr, cmsg) __cmsg_nxthdr((mhdr), (cmsg))
 #define CMSG_ALIGN(len) ( ((len)+sizeof(long)-1) & ~(sizeof(long)-1) )
-#define CMSG_DATA(cmsg) ((void*)((char*)(cmsg) + CMSG_ALIGN(sizeof(struct cmsghdr))))
+#define CMSG_DATA(cmsg) (((unsigned char*)(cmsg) + CMSG_ALIGN(sizeof(struct cmsghdr))))
 #define CMSG_SPACE(len) (CMSG_ALIGN(sizeof(struct cmsghdr)) + CMSG_ALIGN(len))
 #define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr)) + (len))
 #define CMSG_FIRSTHDR(msg) \