For some reason I'm getting lots of duplicate shares on HOdl (windows avx2 version)
First time I'm noticing this, and I'm pretty sure that didn't happen before 3.8.2
********** cpuminer-opt 3.8.2.1 ***********
A CPU miner with multi algo support and optimized for CPUs
with AES_NI and AVX2 and SHA extensions.
BTC donation address: 12tdvfF7KmAsihBXQXynT6E6th2c2pByTT
CPU: Intel(R) Core(TM) i5-7600K CPU @ 3.80GHz.
SW built on Feb 17 2018 with GCC 5.3.1.
CPU features: SSE2 AES AVX AVX2.
SW features: SSE2 AES AVX AVX2.
Algo features: SSE2 AES AVX AVX2.
Start mining with AES AVX2.
[2018-02-18 20:55:13] Starting Stratum on stratum+tcp://hodl.EU.nicehash.com:3352
[2018-02-18 20:55:13] 4 miner threads started, using 'hodl' algorithm.
[2018-02-18 20:55:13] Stratum difficulty set to 4
[2018-02-18 20:55:16] Share submitted.
[2018-02-18 20:55:16] Accepted 1/1 (100%), 828 H, 512.19 H/s
[2018-02-18 20:55:18] Share submitted.
[2018-02-18 20:55:18] Accepted 2/2 (100%), 757 H, 532.64 H/s
[2018-02-18 20:55:21] Share submitted.
[2018-02-18 20:55:21] Accepted 3/3 (100%), 837 H, 560.42 H/s
[2018-02-18 20:55:23] Share submitted.
[2018-02-18 20:55:23] Accepted 4/4 (100%), 771 H, 503.08 H/s
[2018-02-18 20:55:23] Share submitted.
[2018-02-18 20:55:23] Rejected 1/5 (20.0%), 630 H, 459.92 H/s
[2018-02-18 20:55:23] reject reason: Duplicate share.
[2018-02-18 20:55:35] Share submitted.
[2018-02-18 20:55:35] Accepted 5/6 (83.3%), 816 H, 574.61 H/s
[2018-02-18 20:55:35] Share submitted.
[2018-02-18 20:55:35] Rejected 2/7 (28.6%), 723 H, 561.40 H/s
[2018-02-18 20:55:35] reject reason: Duplicate share.
[2018-02-18 20:55:35] Share submitted.
[2018-02-18 20:55:35] Rejected 3/8 (37.5%), 682 H, 552.16 H/s
[2018-02-18 20:55:35] reject reason: Duplicate share.
[2018-02-18 20:55:36] Share submitted.
[2018-02-18 20:55:36] Accepted 6/9 (66.7%), 510 H, 499.41 H/s
[2018-02-18 20:55:42] Share submitted.
[2018-02-18 20:55:42] Accepted 7/10 (70.0%), 967 H, 626.66 H/s
[2018-02-18 20:55:43] Share submitted.
[2018-02-18 20:55:43] Accepted 8/11 (72.7%), 739 H, 501.68 H/s
[2018-02-18 20:55:47] Share submitted.
[2018-02-18 20:55:47] Accepted 9/12 (75.0%), 1020 H, 654.92 H/s
[2018-02-18 20:55:47] Share submitted.
[2018-02-18 20:55:47] Share submitted.
[2018-02-18 20:55:47] Accepted 10/13 (76.9%), 529 H, 378.55 H/s
[2018-02-18 20:55:47] Rejected 4/14 (28.6%), 529 H, 378.55 H/s
[2018-02-18 20:55:47] reject reason: Duplicate share.
[2018-02-18 20:55:50] Share submitted.
[2018-02-18 20:55:50] Accepted 11/15 (73.3%), 462 H, 358.32 H/s
[2018-02-18 20:55:53] Share submitted.
[2018-02-18 20:55:53] Accepted 12/16 (75.0%), 944 H, 611.74 H/s
[2018-02-18 20:55:56] Share submitted.
[2018-02-18 20:55:56] Accepted 13/17 (76.5%), 902 H, 629.96 H/s
[2018-02-18 20:55:59] Share submitted.
[2018-02-18 20:55:59] Accepted 14/18 (77.8%), 800 H, 497.32 H/s
[2018-02-18 20:56:00] Share submitted.
[2018-02-18 20:56:00] Rejected 5/19 (26.3%), 800 H, 527.84 H/s
[2018-02-18 20:56:00] reject reason: Duplicate share.
[2018-02-18 20:56:09] Share submitted.
[2018-02-18 20:56:09] Accepted 15/20 (75.0%), 953 H, 495.64 H/s
[2018-02-18 20:56:10] Share submitted.
[2018-02-18 20:56:10] Accepted 16/21 (76.2%), 813 H, 480.12 H/s
[2018-02-18 20:56:11] Share submitted.
[2018-02-18 20:56:11] Accepted 17/22 (77.3%), 930 H, 627.86 H/s
[2018-02-18 20:56:23] Share submitted.
[2018-02-18 20:56:23] Accepted 18/23 (78.3%), 903 H, 604.42 H/s
[2018-02-18 20:56:26] Share submitted.
[2018-02-18 20:56:26] Accepted 19/24 (79.2%), 963 H, 634.86 H/s
[2018-02-18 20:56:28] Share submitted.
[2018-02-18 20:56:28] Accepted 20/25 (80.0%), 885 H, 581.31 H/s
[2018-02-18 20:56:38] Share submitted.
[2018-02-18 20:56:38] Accepted 21/26 (80.8%), 983 H, 647.70 H/s
[2018-02-18 20:56:41] Share submitted.
[2018-02-18 20:56:41] Accepted 22/27 (81.5%), 836 H, 575.98 H/s
[2018-02-18 20:56:50] Share submitted.
[2018-02-18 20:56:50] Accepted 23/28 (82.1%), 1017 H, 551.69 H/s
[2018-02-18 20:56:55] Share submitted.
[2018-02-18 20:56:55] Accepted 24/29 (82.8%), 850 H, 580.15 H/s
[2018-02-18 20:56:56] Share submitted.
[2018-02-18 20:56:57] Accepted 25/30 (83.3%), 589 H, 453.69 H/s
[2018-02-18 20:56:59] Share submitted.
[2018-02-18 20:56:59] Accepted 26/31 (83.9%), 838 H, 504.05 H/s
[2018-02-18 20:57:02] Share submitted.
[2018-02-18 20:57:02] Accepted 27/32 (84.4%), 901 H, 597.33 H/s
[2018-02-18 20:57:04] Share submitted.
[2018-02-18 20:57:04] Accepted 28/33 (84.8%), 829 H, 592.27 H/s
[2018-02-18 20:57:05] Share submitted.
[2018-02-18 20:57:05] Accepted 29/34 (85.3%), 828 H, 580.02 H/s
[2018-02-18 20:57:05] Share submitted.
[2018-02-18 20:57:06] Rejected 6/35 (17.1%), 742 H, 556.84 H/s
[2018-02-18 20:57:06] reject reason: Duplicate share.
[2018-02-18 20:57:08] Share submitted.
[2018-02-18 20:57:08] Accepted 30/36 (83.3%), 760 H, 466.53 H/s
[2018-02-18 20:57:22] Share submitted.
[2018-02-18 20:57:22] Accepted 31/37 (83.8%), 906 H, 620.70 H/s
[2018-02-18 20:57:32] Share submitted.
[2018-02-18 20:57:32] Accepted 32/38 (84.2%), 804 H, 559.32 H/s
[2018-02-18 20:57:33] Share submitted.
[2018-02-18 20:57:33] Rejected 7/39 (17.9%), 778 H, 553.00 H/s
[2018-02-18 20:57:33] reject reason: Duplicate share.
[2018-02-18 20:57:39] Share submitted.
[2018-02-18 20:57:39] Accepted 33/40 (82.5%), 883 H, 570.50 H/s
[2018-02-18 20:57:40] Share submitted.
[2018-02-18 20:57:40] Accepted 34/41 (82.9%), 881 H, 538.16 H/s
[2018-02-18 20:57:43] Share submitted.
[2018-02-18 20:57:43] Accepted 35/42 (83.3%), 777 H, 520.58 H/s
[2018-02-18 20:57:48] Share submitted.
[2018-02-18 20:57:48] Accepted 36/43 (83.7%), 764 H, 462.16 H/s
[2018-02-18 20:57:52] Share submitted.
[2018-02-18 20:57:52] Accepted 37/44 (84.1%), 803 H, 562.67 H/s
[2018-02-18 20:57:53] Share submitted.
[2018-02-18 20:57:53] Accepted 38/45 (84.4%), 564 H, 420.31 H/s
[2018-02-18 20:57:56] Share submitted.
[2018-02-18 20:57:56] Accepted 39/46 (84.8%), 781 H, 511.72 H/s
[2018-02-18 20:57:57] Share submitted.
[2018-02-18 20:57:57] Rejected 8/47 (17.0%), 719 H, 490.55 H/s
[2018-02-18 20:57:57] reject reason: Duplicate share.
[2018-02-18 20:58:02] Share submitted.
[2018-02-18 20:58:02] Accepted 40/48 (83.3%), 923 H, 607.02 H/s
[2018-02-18 20:58:05] Share submitted.
[2018-02-18 20:58:05] Accepted 41/49 (83.7%), 842 H, 594.09 H/s
[2018-02-18 20:58:11] Share submitted.
[2018-02-18 20:58:11] Accepted 42/50 (84.0%), 899 H, 572.50 H/s
[2018-02-18 20:58:12] Share submitted.
[2018-02-18 20:58:12] Accepted 43/51 (84.3%), 821 H, 600.97 H/s
[2018-02-18 20:58:13] Stratum difficulty set to 8
[2018-02-18 20:58:14] Share submitted.
[2018-02-18 20:58:14] Accepted 44/52 (84.6%), 1024 H, 663.72 H/s
[2018-02-18 20:58:17] Share submitted.
[2018-02-18 20:58:17] Accepted 45/53 (84.9%), 837 H, 558.85 H/s
[2018-02-18 20:58:22] Share submitted.
[2018-02-18 20:58:22] Accepted 46/54 (85.2%), 771 H, 499.49 H/s
[2018-02-18 20:58:22] Share submitted.
[2018-02-18 20:58:23] Rejected 9/55 (16.4%), 733 H, 493.61 H/s
[2018-02-18 20:58:23] reject reason: Duplicate share.
[2018-02-18 20:58:23] Share submitted.
[2018-02-18 20:58:23] Accepted 47/56 (83.9%), 548 H, 426.37 H/s
[2018-02-18 20:58:27] Share submitted.
[2018-02-18 20:58:27] Accepted 48/57 (84.2%), 801 H, 531.96 H/s
[2018-02-18 20:58:29] Share submitted.
[2018-02-18 20:58:29] Accepted 49/58 (84.5%), 745 H, 499.57 H/s
[2018-02-18 20:58:39] Share submitted.
[2018-02-18 20:58:39] Accepted 50/59 (84.7%), 946 H, 549.25 H/s
[2018-02-18 20:58:42] Share submitted.
[2018-02-18 20:58:42] Accepted 51/60 (85.0%), 934 H, 580.80 H/s
[2018-02-18 20:58:56] Share submitted.
[2018-02-18 20:58:57] Accepted 52/61 (85.2%), 854 H, 535.76 H/s
[2018-02-18 20:59:07] Share submitted.
[2018-02-18 20:59:07] Accepted 53/62 (85.5%), 934 H, 531.44 H/s
[2018-02-18 20:59:14] Share submitted.
[2018-02-18 20:59:14] Accepted 54/63 (85.7%), 813 H, 558.06 H/s
[2018-02-18 20:59:23] Share submitted.
[2018-02-18 20:59:23] Accepted 55/64 (85.9%), 831 H, 562.15 H/s
[2018-02-18 20:59:23] Share submitted.
[2018-02-18 20:59:23] Rejected 10/65 (15.4%), 709 H, 538.59 H/s
[2018-02-18 20:59:23] reject reason: Duplicate share.
[2018-02-18 20:59:46] Share submitted.
[2018-02-18 20:59:46] Accepted 56/66 (84.8%), 1036 H, 618.62 H/s
[2018-02-18 20:59:48] Share submitted.
[2018-02-18 20:59:48] Accepted 57/67 (85.1%), 1036 H, 635.54 H/s
[2018-02-18 20:59:49] Share submitted.
[2018-02-18 20:59:49] Accepted 58/68 (85.3%), 972 H, 612.73 H/s
[2018-02-18 21:00:04] Share submitted.
[2018-02-18 21:00:04] Accepted 59/69 (85.5%), 854 H, 576.46 H/s
[2018-02-18 21:00:09] Share submitted.
[2018-02-18 21:00:09] Accepted 60/70 (85.7%), 780 H, 488.07 H/s
EDIT:
I think it's Nicehash only issue
Mining on another pool seems fine
********** cpuminer-opt 3.8.2.1 ***********
A CPU miner with multi algo support and optimized for CPUs
with AES_NI and AVX2 and SHA extensions.
BTC donation address: 12tdvfF7KmAsihBXQXynT6E6th2c2pByTT
CPU: Intel(R) Core(TM) i5-7600K CPU @ 3.80GHz.
SW built on Feb 17 2018 with GCC 5.3.1.
CPU features: SSE2 AES AVX AVX2.
SW features: SSE2 AES AVX AVX2.
Algo features: SSE2 AES AVX AVX2.
Start mining with AES AVX2.
[2018-02-18 21:30:00] Starting Stratum on stratum+tcp://roi.suprnova.cc:4699
[2018-02-18 21:30:00] 4 miner threads started, using 'hodl' algorithm.
[2018-02-18 21:30:01] Stratum difficulty set to 8
[2018-02-18 21:30:20] Share submitted.
[2018-02-18 21:30:20] Accepted 1/1 (100%), 880 H, 455.67 H/s
[2018-02-18 21:30:23] Share submitted.
[2018-02-18 21:30:23] Accepted 2/2 (100%), 764 H, 462.02 H/s
[2018-02-18 21:30:31] Share submitted.
[2018-02-18 21:30:31] Accepted 3/3 (100%), 919 H, 538.87 H/s
[2018-02-18 21:31:00] Stratum difficulty set to 14.5455
[2018-02-18 21:31:04] Share submitted.
[2018-02-18 21:31:04] Accepted 4/4 (100%), 904 H, 561.84 H/s
[2018-02-18 21:31:06] Share submitted.
[2018-02-18 21:31:06] Accepted 5/5 (100%), 972 H, 607.93 H/s
[2018-02-18 21:31:55] Stratum difficulty set to 4.40771
[2018-02-18 21:32:03] Share submitted.
[2018-02-18 21:32:03] Accepted 6/6 (100%), 813 H, 446.92 H/s
[2018-02-18 21:32:08] Share submitted.
[2018-02-18 21:32:08] Share submitted.
[2018-02-18 21:32:08] Accepted 7/7 (100%), 554 H, 379.70 H/s
[2018-02-18 21:32:08] Accepted 8/8 (100%), 554 H, 379.70 H/s
[2018-02-18 21:32:10] Share submitted.
[2018-02-18 21:32:10] Accepted 9/9 (100%), 608 H, 384.08 H/s
[2018-02-18 21:32:15] Share submitted.
[2018-02-18 21:32:16] Accepted 10/10 (100%), 748 H, 516.28 H/s
[2018-02-18 21:32:18] Share submitted.
[2018-02-18 21:32:18] Accepted 11/11 (100%), 540 H, 369.01 H/s
[2018-02-18 21:32:18] Share submitted.
[2018-02-18 21:32:18] Accepted 12/12 (100%), 452 H, 361.97 H/s
[2018-02-18 21:32:23] Share submitted.
[2018-02-18 21:32:23] Accepted 13/13 (100%), 998 H, 566.35 H/s
[2018-02-18 21:32:26] Share submitted.
[2018-02-18 21:32:26] Accepted 14/14 (100%), 843 H, 508.53 H/s
[2018-02-18 21:32:28] Share submitted.
[2018-02-18 21:32:28] Accepted 15/15 (100%), 719 H, 464.78 H/s
[2018-02-18 21:32:33] Share submitted.
[2018-02-18 21:32:33] Accepted 16/16 (100%), 792 H, 441.48 H/s
[2018-02-18 21:32:41] Share submitted.
[2018-02-18 21:32:42] Accepted 17/17 (100%), 772 H, 502.26 H/s
[2018-02-18 21:32:44] Share submitted.
[2018-02-18 21:32:44] Accepted 18/18 (100%), 683 H, 421.64 H/s
[2018-02-18 21:32:50] Stratum difficulty set to 10.4946
[2018-02-18 21:32:57] Share submitted.
[2018-02-18 21:32:57] Accepted 19/19 (100%), 1038 H, 650.49 H/s
[2018-02-18 21:32:58] Share submitted.
[2018-02-18 21:32:58] Accepted 20/20 (100%), 843 H, 570.27 H/s
[2018-02-18 21:33:14] Share submitted.
[2018-02-18 21:33:14] Accepted 21/21 (100%), 922 H, 525.04 H/s
[2018-02-18 21:33:34] Share submitted.
[2018-02-18 21:33:34] Accepted 22/22 (100%), 971 H, 594.49 H/s
[2018-02-18 21:33:41] Share submitted.
[2018-02-18 21:33:41] Accepted 23/23 (100%), 918 H, 571.24 H/s
[2018-02-18 21:34:02] Share submitted.
[2018-02-18 21:34:02] Accepted 24/24 (100%), 996 H, 614.81 H/s
[2018-02-18 21:34:05] Share submitted.
[2018-02-18 21:34:05] Accepted 25/25 (100%), 760 H, 441.58 H/s
[2018-02-18 21:34:08] Share submitted.
[2018-02-18 21:34:08] Accepted 26/26 (100%), 841 H, 557.85 H/s
[2018-02-18 21:34:18] Share submitted.
[2018-02-18 21:34:18] Accepted 27/27 (100%), 886 H, 546.23 H/s
[2018-02-18 21:34:29] Share submitted.
[2018-02-18 21:34:29] Accepted 28/28 (100%), 869 H, 577.68 H/s
[2018-02-18 21:34:30] Share submitted.
[2018-02-18 21:34:31] Accepted 29/29 (100%), 620 H, 450.94 H/s
[2018-02-18 21:34:31] Share submitted.
[2018-02-18 21:34:31] Accepted 30/30 (100%), 476 H, 409.03 H/s