diff --git a/src/copyin.c b/src/copyin.c
index 09f226b..d505407 100644
--- a/src/copyin.c
+++ b/src/copyin.c
@@ -178,7 +178,7 @@ list_file(struct cpio_file_stat* file_hdr, int in_file_des)
 #endif
       if (crc != file_hdr->c_chksum)
 	{
-	  error (0, 0, _("%s: checksum error (0x%lx, should be 0x%lx)"),
+	  error (0, 0, _("%s: checksum error (0x%x, should be 0x%x)"),
 		 file_hdr->c_name, crc, file_hdr->c_chksum);
 	}
     }
@@ -525,7 +525,7 @@ copyin_regular_file (struct cpio_file_stat* file_hdr, int in_file_des)
       if (archive_format == arf_crcascii)
 	{
 	  if (crc != file_hdr->c_chksum)
-	    error (0, 0, _("%s: checksum error (0x%lx, should be 0x%lx)"),
+	    error (0, 0, _("%s: checksum error (0x%x, should be 0x%x)"),
 		   file_hdr->c_name, crc, file_hdr->c_chksum);
 	}
       tape_skip_padding (in_file_des, file_hdr->c_filesize);
@@ -550,7 +550,7 @@ copyin_regular_file (struct cpio_file_stat* file_hdr, int in_file_des)
   if (archive_format == arf_crcascii)
     {
       if (crc != file_hdr->c_chksum)
-	error (0, 0, _("%s: checksum error (0x%lx, should be 0x%lx)"),
+	error (0, 0, _("%s: checksum error (0x%x, should be 0x%x)"),
 	       file_hdr->c_name, crc, file_hdr->c_chksum);
     }
 
@@ -1442,7 +1442,7 @@ process_copy_in ()
 	    tape_skip_padding (in_file_des, file_hdr.c_filesize);
 	    if (crc != file_hdr.c_chksum)
 	      {
-		error (0, 0, _("%s: checksum error (0x%lx, should be 0x%lx)"),
+		error (0, 0, _("%s: checksum error (0x%x, should be 0x%x)"),
 		       file_hdr.c_name, crc, file_hdr.c_chksum);
 	      }
          /* Debian hack: -v and -V now work with --only-verify-crc.
diff --git a/src/copyout.c b/src/copyout.c
index 72f1989..03eaf88 100644
--- a/src/copyout.c
+++ b/src/copyout.c
@@ -33,10 +33,10 @@
 /* Read FILE_SIZE bytes of FILE_NAME from IN_FILE_DES and
    compute and return a checksum for them.  */
 
-static unsigned long
+static uint32_t
 read_for_checksum (int in_file_des, int file_size, char *file_name)
 {
-  unsigned long crc;
+  uint32_t crc;
   char buf[BUFSIZ];
   int bytes_left;
   int bytes_read;
diff --git a/src/cpiohdr.h b/src/cpiohdr.h
index bb1ad6b..1c11998 100644
--- a/src/cpiohdr.h
+++ b/src/cpiohdr.h
@@ -123,7 +123,7 @@ struct cpio_file_stat /* Internal representation of a CPIO header */
   long c_rdev_maj;
   long c_rdev_min;
   size_t c_namesize;
-  unsigned long c_chksum;
+  uint32_t c_chksum;
   char *c_name;
   char *c_tar_linkname;
 };
diff --git a/src/extern.h b/src/extern.h
index 4f94d40..3530bf6 100644
--- a/src/extern.h
+++ b/src/extern.h
@@ -75,7 +75,7 @@ extern char *new_media_message_after_number;
 extern int archive_des;
 extern char *archive_name;
 extern char *rsh_command_option;
-extern unsigned long crc;
+extern uint32_t crc;
 extern int delayed_seek_count;
 #ifdef DEBUG_CPIO
 extern int debug_flag;
diff --git a/src/global.c b/src/global.c
index cff9720..336941e 100644
--- a/src/global.c
+++ b/src/global.c
@@ -144,7 +144,7 @@ char *archive_name = NULL;
 char *rsh_command_option = NULL;
 
 /* CRC checksum.  */
-unsigned long crc;
+uint32_t crc;
 
 /* Input and output buffers.  */
 char *input_buffer, *output_buffer;