diff --git a/sxt/rdb.c b/sxt/rdb.c
index c83892d..56c73a3 100644
--- a/sxt/rdb.c
+++ b/sxt/rdb.c
@@ -502,7 +502,7 @@ uint32_t sxtrdb_print_va(sxtrdb_t *b, const char *fmt, int argc, va_list ap)
     case 's':
       cstr = (char *)va_arg(ap, char *);
       clen = strlen(cstr);
-      r = sxtrdb_write_u32(b, clen);
+      r = sxtrdb_write_u32(b, (uint32_t)clen);
       if(r != sizeof(uint32_t)) return 0;
       else len += r;
       r = sxtrdb_write_raw(b, cstr, clen);
@@ -513,7 +513,7 @@ uint32_t sxtrdb_print_va(sxtrdb_t *b, const char *fmt, int argc, va_list ap)
       clen = va_arg(ap, size_t);
       d._dp = va_arg(ap, void *);
       count++;
-      r = sxtrdb_write_raw(b, d._dp, clen);
+      r = sxtrdb_write_raw(b, d._dp, (uint32_t)clen);
       if(r != clen) return 0;
       else len += clen;
       break;