diff --git a/ChangeLog b/ChangeLog
index b9b6bae00f075fff7451d9742ed6cd51b2f1fd16..7ad04cbed4427d148af0a220940ada93ea369473 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -20,6 +20,12 @@
 	* testsuite/yarrow-test.c (test_main): Fix pointer
 	signednesss warning.
 
+	* testsuite/testutils.c (test_armor): Change ascii argument to
+	const char *.
+	* testsuite/base16-test.c (test_main): Use LDATA for the non-ascii
+	argument to test_armor.
+	* testsuite/base64-test.c (test_main): Likewise.
+
 2016-08-29  Niels Möller  <nisse@lysator.liu.se>
 
 	* sexp-format.c (strlen_u8): New helper function.
diff --git a/testsuite/base16-test.c b/testsuite/base16-test.c
index 633e1c6d2e63d25060a610b9ca6fc40777598573..820915b70212d7d7973afb8f8d340c40f9f81999 100644
--- a/testsuite/base16-test.c
+++ b/testsuite/base16-test.c
@@ -14,12 +14,12 @@ test_main(void)
   ASSERT(BASE16_DECODE_LENGTH(3) == 2);
   ASSERT(BASE16_DECODE_LENGTH(4) == 2);
   
-  test_armor(&nettle_base16, 0, "", "");
-  test_armor(&nettle_base16, 1, "H", "48");
-  test_armor(&nettle_base16, 2, "He", "4865");
-  test_armor(&nettle_base16, 3, "Hel", "48656c");
-  test_armor(&nettle_base16, 4, "Hell", "48656c6c");
-  test_armor(&nettle_base16, 5, "Hello", "48656c6c6f");
-  test_armor(&nettle_base16, 6, "Hello", "48656c6c6f00");
+  test_armor(&nettle_base16, LDATA(""), "");
+  test_armor(&nettle_base16, LDATA("H"), "48");
+  test_armor(&nettle_base16, LDATA("He"), "4865");
+  test_armor(&nettle_base16, LDATA("Hel"), "48656c");
+  test_armor(&nettle_base16, LDATA("Hell"), "48656c6c");
+  test_armor(&nettle_base16, LDATA("Hello"), "48656c6c6f");
+  test_armor(&nettle_base16, LDATA("Hello\0"), "48656c6c6f00");
 }
   
diff --git a/testsuite/base64-test.c b/testsuite/base64-test.c
index bdf8415a9fdd21b3478e6fc1fa3fc5fa1c820d17..f366a413843731a19916e1d9121831e2f993e809 100644
--- a/testsuite/base64-test.c
+++ b/testsuite/base64-test.c
@@ -84,25 +84,25 @@ test_main(void)
   ASSERT(BASE64_DECODE_LENGTH(3) == 3); /* At most 24 bits */
   ASSERT(BASE64_DECODE_LENGTH(4) == 3); /* At most 30 bits */
   
-  test_armor(&nettle_base64, 0, "", "");
-  test_armor(&nettle_base64, 1, "H", "SA==");
-  test_armor(&nettle_base64, 2, "He", "SGU=");
-  test_armor(&nettle_base64, 3, "Hel", "SGVs");
-  test_armor(&nettle_base64, 4, "Hell", "SGVsbA==");
-  test_armor(&nettle_base64, 5, "Hello", "SGVsbG8=");
-  test_armor(&nettle_base64, 6, "Hello", "SGVsbG8A");
-  test_armor(&nettle_base64, 9, "Hello?>>>", "SGVsbG8/Pj4+");
-  test_armor(&nettle_base64, 4, "\xff\xff\xff\xff", "/////w==");
+  test_armor(&nettle_base64, LDATA(""), "");
+  test_armor(&nettle_base64, LDATA("H"), "SA==");
+  test_armor(&nettle_base64, LDATA("He"), "SGU=");
+  test_armor(&nettle_base64, LDATA("Hel"), "SGVs");
+  test_armor(&nettle_base64, LDATA("Hell"), "SGVsbA==");
+  test_armor(&nettle_base64, LDATA("Hello"), "SGVsbG8=");
+  test_armor(&nettle_base64, LDATA("Hello\0"), "SGVsbG8A");
+  test_armor(&nettle_base64, LDATA("Hello?>>>"), "SGVsbG8/Pj4+");
+  test_armor(&nettle_base64, LDATA("\xff\xff\xff\xff"), "/////w==");
 
-  test_armor(&nettle_base64url, 0, "", "");
-  test_armor(&nettle_base64url, 1, "H", "SA==");
-  test_armor(&nettle_base64url, 2, "He", "SGU=");
-  test_armor(&nettle_base64url, 3, "Hel", "SGVs");
-  test_armor(&nettle_base64url, 4, "Hell", "SGVsbA==");
-  test_armor(&nettle_base64url, 5, "Hello", "SGVsbG8=");
-  test_armor(&nettle_base64url, 6, "Hello", "SGVsbG8A");
-  test_armor(&nettle_base64url, 9, "Hello?>>>", "SGVsbG8_Pj4-");
-  test_armor(&nettle_base64url, 4, "\xff\xff\xff\xff", "_____w==");
+  test_armor(&nettle_base64url, LDATA(""), "");
+  test_armor(&nettle_base64url, LDATA("H"), "SA==");
+  test_armor(&nettle_base64url, LDATA("He"), "SGU=");
+  test_armor(&nettle_base64url, LDATA("Hel"), "SGVs");
+  test_armor(&nettle_base64url, LDATA("Hell"), "SGVsbA==");
+  test_armor(&nettle_base64url, LDATA("Hello"), "SGVsbG8=");
+  test_armor(&nettle_base64url, LDATA("Hello\0"), "SGVsbG8A");
+  test_armor(&nettle_base64url, LDATA("Hello?>>>"), "SGVsbG8_Pj4-");
+  test_armor(&nettle_base64url, LDATA("\xff\xff\xff\xff"), "_____w==");
 
   {
     /* Test overlapping areas */
diff --git a/testsuite/testutils.c b/testsuite/testutils.c
index 01c9b944cd5ea6eee9e082dc2e4d52c211f14939..6f897617cadbd23077a5adbeac91d73c671140e5 100644
--- a/testsuite/testutils.c
+++ b/testsuite/testutils.c
@@ -563,7 +563,7 @@ void
 test_armor(const struct nettle_armor *armor,
            size_t data_length,
            const uint8_t *data,
-           const uint8_t *ascii)
+           const char *ascii)
 {
   size_t ascii_length = strlen(ascii);
   uint8_t *buffer = xalloc(1 + ascii_length);
diff --git a/testsuite/testutils.h b/testsuite/testutils.h
index 2f74dc7c3e5f978fb2717b7282d3372e82c01ca9..7c44772b7748d07397304c838c087897112f1cc9 100644
--- a/testsuite/testutils.h
+++ b/testsuite/testutils.h
@@ -160,7 +160,7 @@ void
 test_armor(const struct nettle_armor *armor,
            size_t data_length,
            const uint8_t *data,
-           const uint8_t *ascii);
+           const char *ascii);
 
 #if WITH_HOGWEED
 #ifndef mpn_zero_p