diff --git a/unzip/crypt.h b/unzip/crypt.h
index f4b93b78..8bde464b 100644
--- a/unzip/crypt.h
+++ b/unzip/crypt.h
@@ -50,7 +50,7 @@ static int update_keys(unsigned long* pkeys, const z_crc_t* pcrc_32_tab, int c)
     (*(pkeys+1)) += (*(pkeys+0)) & 0xff;
     (*(pkeys+1)) = (*(pkeys+1)) * 134775813L + 1;
     {
-      register int keyshift = (int)((*(pkeys+1)) >> 24);
+      int keyshift = (int)((*(pkeys+1)) >> 24);
       (*(pkeys+2)) = CRC32((*(pkeys+2)), keyshift);
     }
     return c;