archive-tar: keep const in checksum calculation

diff --git a/archive-tar.c b/archive-tar.c
index 20af0051a334a1357b055ea10d74f5380117ab68..55cccecadf41558aa780434eb23262a537df9232 100644 (file)
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -101,13 +101,13 @@ static void strbuf_append_ext_header(struct strbuf *sb, const char *keyword,
 
 static unsigned int ustar_header_chksum(const struct ustar_header *header)
 {
-       char *p = (char *)header;
+       const char *p = (const char *)header;
        unsigned int chksum = 0;
        while (p < header->chksum)
                chksum += *p++;
        chksum += sizeof(header->chksum) * ' ';
        p += sizeof(header->chksum);
-       while (p < (char *)header + sizeof(struct ustar_header))
+       while (p < (const char *)header + sizeof(struct ustar_header))
                chksum += *p++;
        return chksum;
 }