byte[] b3 = "????".getBytes(Charsets.US_ASCII);
    byte[] b4 = "ニュース".getBytes(Charsets.US_ASCII);
    byte[] b5 = "スューー".getBytes(Charsets.US_ASCII);
    // Assert they are all equal (using the transitive property)
    assertTrue(Arrays.equals(b1, b2));
    assertTrue(Arrays.equals(b2, b3));
    assertTrue(Arrays.equals(b3, b4));
    assertTrue(Arrays.equals(b4, b5));
  }

			b0, b5, b10, b15 = qr(b0, b5, b10, b15)
			b1, b6, b11, b12 = qr(b1, b6, b11, b12)
			b2, b7, b8, b13 = qr(b2, b7, b8, b13)
			b3, b4, b9, b14 = qr(b3, b4, b9, b14)
		}

		// Store block i back into b[*][i].
		// Add b4..b11 back to the original key material,
		// like in ChaCha20, to avoid trivial invertibility.
		// There is no entropy in b0..b3 and b12..b15

		Bloc("entry",
			Valu("mem", OpInitMem, types.TypeMem, 0, nil),
			Valu("cond", OpConstBool, c.config.Types.Bool, 0, nil),
			If("cond", "b2", "b4")),
		Bloc("b2",
			If("cond", "b3", "b4")),
		Bloc("b3",
			If("cond", "b3", "b4")),
		Bloc("b4",
			If("cond", "b3", "exit")),
		Bloc("exit",
			Exit("mem")))

	CheckFunc(fun.f)
	Opt(fun.f)
	CheckFunc(fun.f)
	Deadcode(fun.f)

00000300  93 f6 27 74 24 b4 e2 3d  22 04 30 a0 d6 5b c8 da  |..'t$..=".0..[..|
00000310  6e 56 30 d4 fb 86 fd 76  8f 1b 47 c0 55 95 cd 15  |nV0....v..G.U...|
00000320  bf a7 27 ce 2d c3 43 6b  ed 2d 09 bb eb 55 73 c9  |..'.-.Ck.-...Us.|
00000330  2c ee cd 23 af d9 1c 51  1d 0c 00 14 01 61 8a fd  |,..#...Q.....a..|
00000340  8f 95 d1 ce 32 57 ae 2b  09 15 b4 86 41 1e 74 f5  |....2W.+....A.t.|

00000180  bf d8 ec 4e 9f 69 27 c8  89 fc 18 21 58 8a ba 87  |...N.i'....!X...|
00000190  23 4c cd 95 b7 f1 a5 9a  79 5c d7 35 74 a5 4a 2c  |#L......y\.5t.J,|
000001a0  fc c8 f4 b4 c4 de 3b 0e  08 12 e0 24 af 10 b3 e7  |......;....$....|
000001b0  04 74 a9 b4 de ee 98 b5  f1 ed 50 9f eb 5f eb 14  |.t........P.._..|
000001c0  56 6f d2 f2 b3 5e 40 34  0a f9 2d 44 de 0a 29 8f  |Vo...^@4..-D..).|

000000a0  89 f3 d1 fd 3e 46 c2 50  01 24 72 2a 64 98 17 03  |....>F.P.$r*d...|
000000b0  03 02 6d 40 bc da 1a 9c  8b d7 15 24 4f d4 c1 9c  |..m@.......$O...|
000000c0  8b 3c 8b 51 37 41 46 a8  cb b4 9c 50 c0 be 72 ef  |.<.Q7AF....P..r.|
000000d0  81 d3 7f ed ec 96 e2 c2  08 0e 7e 23 95 c3 4f 79  |..........~#..Oy|
000000e0  01 2d 26 81 c1 ba d0 58  61 d8 c5 b7 e7 79 4f 3e  |.-&....Xa....yO>|

000000b0  1d 00 20 49 31 09 86 3b  71 6b ff 6c bc 6f 40 4c  |.. I1..;qk.l.o@L|
000000c0  3a 04 44 c3 83 6c 9b 1d  99 a6 10 c7 07 f9 9d 57  |:.D..l.........W|
000000d0  2d b4 59 00 29 00 94 00  6f 00 69 00 00 00 00 00  |-.Y.)...o.i.....|
000000e0  00 00 00 00 00 00 00 00  00 00 00 94 68 2d a3 82  |............h-..|
000000f0  51 ed 14 ef 68 ca 42 c5  5c 95 7a 77 9a 7a 61 99  |Q...h.B.\.zw.za.|

# golang.org/issue/25542.
name: noprev1
A: B4 C2
B2.hidden:
C2:
build A:               A B4        C2
downgrade A B2.hidden: A B2.hidden C2

name: noprev2
A: B4 C2
B2.hidden:
B1:
C2:
build A:               A B4        C2
downgrade A B2.hidden: A B2.hidden C2

name: noprev3
A: B4 C2
B3:
B2.hidden:
C2:
build A:               A B4        C2
downgrade A B2.hidden: A B2.hidden C2

000000a0  41 17 03 03 01 50 c0 1e  e0 f5 55 6e 92 52 99 d8  |A....P....Un.R..|
000000b0  62 06 9a 59 c7 b0 d7 5e  c9 6d 76 a6 7a c9 55 fe  |b..Y...^.mv.z.U.|
000000c0  83 d5 84 fc 3c f0 02 fe  0f f8 b4 2e a0 45 29 cd  |....<........E).|
000000d0  37 ea 9d 2e 75 c4 06 1e  58 5f 21 31 4b 8c 5e 91  |7...u...X_!1K.^.|
000000e0  83 c1 0d 2c 21 68 1b 05  85 d2 35 1c 36 ee 9c b2  |...,!h....5.6...|

00000030  6f f4 cb 8a 13 74 a2 ee  b7 27 69 b4 41 c0 90 68  |o....t...'i.A..h|
00000040  bc 02 69 e1 c6 48 4f 39  36 30 25 ca 4c 17 ce 83  |..i..HO960%.L...|
00000050  9e 08 56 e3 05 49 93 9e  2e c4 fb e6 c8 01 f1 0f  |..V..I..........|
00000060  c5 70 0f 08 83 48 e9 48  ef 6e 50 8b 05 7e e5 84  |.p...H.H.nP..~..|
00000070  25 fa 55 c7 ae 31 02 27  00 ef 3f 98 86 20 12 89  |%.U..1.'..?.. ..|