| !! latest version !! Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: AliceRoselia
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Simplify futility pruning Passed non regression STC: https://tests.stockfishchess.org/tests/view/693e642c46f342e1ec20f68d LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 107968 W: 28080 L: 27937 D: 51951 Elo +0.46 Ptnml(0-2): 381, 12708, 27626, 12925, 344 Passed non regression LTC: https://tests.stockfishchess.org/tests/view/693ff10c46f342e1ec20fa6a LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 334266 W: 85271 L: 85370 D: 163625 Elo -0.10 Ptnml(0-2): 179, 36395, 94086, 36292, 181 closes https://github.com/official-stockfish/Stockfish/pull/6484 Bench: 2987379 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Shawn Xu
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Remove Secondary TT Aging Passed VVLTC w/ STC Bounds: LLR: 2.94 (-2.94,2.94) <0.00,2.00> Total: 107006 W: 27676 L: 27326 D: 52004 Elo +1.14 Ptnml(0-2): 21, 9505, 34097, 9863, 17 https://tests.stockfishchess.org/tests/view/6939ac5b75b70713ef796f11 Passed VVLTC w/ LTC Bounds: LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 263190 W: 67547 L: 66837 D: 128806 Elo +0.94 Ptnml(0-2): 32, 23939, 82942, 24651, 31 https://tests.stockfishchess.org/tests/view/692165823b03dd3a060e666d closes https://github.com/official-stockfish/Stockfish/pull/6480 Bench: 2800411 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: sscg13
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Represent threat weights directly as i8 LEB128 adds no additional compression and adds extra complexity to the code currently. closes https://github.com/official-stockfish/Stockfish/pull/6479 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Daniel Monroe
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Remove rootDepth condition in newDepth clamping Passed simplification STC LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 132256 W: 34462 L: 34347 D: 63447 Elo +0.30 Ptnml(0-2): 470, 15625, 33833, 15720, 480 https://tests.stockfishchess.org/tests/view/69325fe0a24a6df719fcca16 Passed simplification LTC LLR: 2.95 (-2.94,2.94) <-1.75,0.25> Total: 128220 W: 32503 L: 32392 D: 63325 Elo +0.30 Ptnml(0-2): 94, 13900, 35982, 14069, 65 https://tests.stockfishchess.org/tests/view/6934c2b3a24a6df719fcdf1e closes https://github.com/official-stockfish/Stockfish/pull/6472 Bench: 2926903 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: ppigazzini
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 chore(ci): bump runner to macos-15 closes https://github.com/official-stockfish/Stockfish/pull/6475 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Pieter te Brake
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Removed redundant board updates Contrary to what the comment says, `remove_piece` does in fact set the relevant `board` elements to `NO_PIECE`. closes https://github.com/official-stockfish/Stockfish/pull/6471 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Timothy Herchen
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Tweak nnue_accumulator indexing ``` LLR: 2.93 (-2.94,2.94) <0.00,2.00> Total: 92736 W: 24149 L: 23764 D: 44823 Elo +1.44 Ptnml(0-2): 280, 10056, 25334, 10395, 303 ``` The use of `IndexType` in the loops is suboptimal because it requires truncation to 32 bits, and thereby defeats some optimizations. Using `size_t` for the loop body works nicely, and a signed index into the index lists allows the compiler to assume the case `added.size() == UINT_MAX`, which would be an infinite loop, to not happen. Passed STC https://tests.stockfishchess.org/tests/live_elo/692fd98ab23dfeae38d01d98 closes https://github.com/official-stockfish/Stockfish/pull/6466 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: mstembera
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Fix one error and all warnings on MSVC 2026 The error is "C1001: Internal compiler error." in uci.cpp on line 370 of master. For some reason the compiler can't handle the std::size(hashfullAges) inside the lambda. Older MSVC versions had no problem. Most of the warnings are due to implicit type conversions "conversion from type A to type B, possible loss of data" many of which have been present for a while. closes https://github.com/official-stockfish/Stockfish/pull/6464 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Daniel Monroe
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Remove non-functional term in isShuffling closes https://github.com/official-stockfish/Stockfish/pull/6462 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Timothy Herchen
Date: Sun Dec 21 15:43:32 2025 +0100 Timestamp: 1766328212 Small threat-related cleanups Remove a couple unused things, mark `noRaysContaining` as `[[maybe_unused]]` (suggested by Viz) to silence a warning on GCC 10, update a comment, and replace inline constants closes https://github.com/official-stockfish/Stockfish/pull/6460 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: FauziAkram
Date: Sun Dec 21 15:43:25 2025 +0100 Timestamp: 1766328205 Simplify piece threat calculation Passed STC: LLR: 2.95 (-2.94,2.94) <-1.75,0.25> Total: 105984 W: 27206 L: 27067 D: 51711 Elo +0.46 Ptnml(0-2): 260, 11556, 29245, 11647, 284 https://tests.stockfishchess.org/tests/view/6914798e7ca87818523317cf Passed LTC: LLR: 2.95 (-2.94,2.94) <-1.75,0.25> Total: 53028 W: 13635 L: 13456 D: 25937 Elo +1.17 Ptnml(0-2): 28, 5184, 15908, 5369, 25 https://tests.stockfishchess.org/tests/view/6918c5fc7ca8781852332312 closes https://github.com/official-stockfish/Stockfish/pull/6459 No functional change see source |
| Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: FauziAkram
Date: Sun Dec 21 15:22:06 2025 +0100 Timestamp: 1766326926 Fix Typo closes https://github.com/official-stockfish/Stockfish/pull/6436 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Timothy Herchen
Date: Wed Dec 3 12:32:29 2025 +0100 Timestamp: 1764761549 fix missing condition Fixes a bug in https://github.com/official-stockfish/Stockfish/pull/6453 https://github.com/official-stockfish/Stockfish/commit/abd835dcbc3a28481224f6253b00b7420d062513 The modifications to the DirtyThreats bitboards should only happen if PutPiece is true. This somehow didn't affect bench at the default parameters. Reference AVX2: ./stockfish.killdeer-fix.avx2 bench 64 1 23 Nodes searched : 178140156 Nodes/second : 1503152 before patch: ./stockfish.master.avx512icl bench 64 1 23 Nodes searched : 218349728 Nodes/second : 1743450 after patch: ./stockfish.killdeer-fix.avx512icl bench 64 1 23 Nodes searched : 178140156 Nodes/second : 1727520 passed STC: LLR: 2.95 (-2.94,2.94) <-1.75,0.25> Total: 39328 W: 10293 L: 10080 D: 18955 Elo +1.88 Ptnml(0-2): 113, 4306, 10629, 4487, 129 https://tests.stockfishchess.org/tests/view/692fb2d8b23dfeae38d01c81 closes https://github.com/official-stockfish/Stockfish/pull/6463 Bench: 2912398 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Daniel Monroe
Date: Mon Dec 1 17:35:34 2025 +0100 Timestamp: 1764606934 Move hindsight reductions above cutoffs Passed STC LLR: 2.93 (-2.94,2.94) <0.00,2.00> Total: 52640 W: 13701 L: 13361 D: 25578 Elo +2.24 Ptnml(0-2): 168, 6143, 13356, 6487, 166 https://tests.stockfishchess.org/tests/view/6918dc407ca8781852332339 Passed LTC LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 207690 W: 53187 L: 52520 D: 101983 Elo +1.12 Ptnml(0-2): 93, 22515, 57994, 23118, 125 https://tests.stockfishchess.org/tests/view/6919dd307ca87818523324c7 closes https://github.com/official-stockfish/Stockfish/pull/6448 Bench: 2912398 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Timothy Herchen
Date: Mon Dec 1 17:26:50 2025 +0100 Timestamp: 1764606410 Improve update_piece_threats passed on avx512ICL: LLR: 2.95 (-2.94,2.94) <0.00,2.00> Total: 30240 W: 8026 L: 7726 D: 14488 Elo +3.45 Ptnml(0-2): 95, 3235, 8171, 3513, 106 https://tests.stockfishchess.org/tests/view/69281d9ab23dfeae38cfeeb8 passed on generic architectures: LLR: 2.94 (-2.94,2.94) <0.00,2.00> Total: 73184 W: 19183 L: 18821 D: 35180 Elo +1.72 Ptnml(0-2): 258, 7988, 19744, 8338, 264 https://tests.stockfishchess.org/tests/view/6928ba11b23dfeae38cff276 subsequent cleanups tested as: LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 72480 W: 18678 L: 18502 D: 35300 Elo +0.84 Ptnml(0-2): 242, 7925, 19718, 8125, 230 https://tests.stockfishchess.org/tests/view/692a26adb23dfeae38cff566 We add an argument noRaysContaining, which skips all discoveries which contain all bits in the argument; if the argument is from | to, then this will eliminate the discovery. Separately, on AVX512ICL we can speed up the computation of DirtyThreats by moving from a pop_lsb loop to a vector extraction with vpcompressb. See PR for details. closes https://github.com/official-stockfish/Stockfish/pull/6453 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Joost VandeVondele
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Update main network to nn-2962dca31855.nnue trained with https://github.com/vondele/nettest/blob/dd921672bd4ad8eb09fa45248078450857e81884/threats.yaml on top off and tested against https://github.com/official-stockfish/Stockfish/pull/6452 passed STC LLR: 2.95 (-2.94,2.94) <0.00,2.00> Total: 130720 W: 34028 L: 33570 D: 63122 Elo +1.22 Ptnml(0-2): 435, 15348, 33384, 15710, 483 https://tests.stockfishchess.org/tests/view/69294539b23dfeae38cff3ad passed LTC LLR: 2.95 (-2.94,2.94) <0.50,2.50> Total: 51144 W: 13140 L: 12794 D: 25210 Elo +2.35 Ptnml(0-2): 38, 5370, 14408, 5720, 36 https://tests.stockfishchess.org/tests/view/692a9c37b23dfeae38cffa4f closes https://github.com/official-stockfish/Stockfish/pull/6457 Bench: 2823033 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: KazApps
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Update AUTHORS (KazApps) closes https://github.com/official-stockfish/Stockfish/pull/6454 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Joost VandeVondele
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Update main network to nn-87a9d7857d88.nnue trained with https://github.com/vondele/nettest/blob/842d95177f882c0e9b5262247c38d8fcb3e0f3db/threats.yaml passed STC: LLR: 2.93 (-2.94,2.94) <0.00,2.00> Total: 114880 W: 30291 L: 29851 D: 54738 Elo +1.33 Ptnml(0-2): 499, 13547, 28947, 13909, 538 https://tests.stockfishchess.org/tests/view/6923ec4bba083df4ca63dd39 passed LTC: LLR: 2.97 (-2.94,2.94) <0.50,2.50> Total: 113268 W: 29115 L: 28634 D: 55519 Elo +1.48 Ptnml(0-2): 114, 12295, 31340, 12766, 119 https://tests.stockfishchess.org/tests/view/6925cd01b23dfeae38cfe134 closes https://github.com/official-stockfish/Stockfish/pull/6452 Bench: 3028457 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: FauziAkram
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Simplify the highBestMoveEffort formula in Time management Passed STC: LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 22272 W: 5885 L: 5655 D: 10732 Elo +3.59 Ptnml(0-2): 76, 2329, 6108, 2535, 88 https://tests.stockfishchess.org/tests/view/69244d07ba083df4ca63e02b Passed LTC: LLR: 2.95 (-2.94,2.94) <-1.75,0.25> Total: 48690 W: 12405 L: 12221 D: 24064 Elo +1.31 Ptnml(0-2): 29, 4755, 14597, 4931, 33 https://tests.stockfishchess.org/tests/view/6924de9aba083df4ca63e327 closes https://github.com/official-stockfish/Stockfish/pull/6451 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Timothy Herchen
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Fix msvc macro closes https://github.com/official-stockfish/Stockfish/pull/6449 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Shawn Xu
Date: Sun Nov 30 21:58:35 2025 +0100 Timestamp: 1764536315 Formatting fixups closes https://github.com/official-stockfish/Stockfish/pull/6446 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: pb00067
Date: Sun Nov 30 21:58:34 2025 +0100 Timestamp: 1764536314 Fix for SF getting stuck during search (issue #5023) Among several passed similar versions this is the simpliest one. Passed STC non-regression https://tests.stockfishchess.org/tests/view/691f3b4aacb6dbdf23d07d11 LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 126368 W: 32607 L: 32489 D: 61272 Elo +0.32 Ptnml(0-2): 408, 13974, 34298, 14100, 404 Passed LTC non-regression https://tests.stockfishchess.org/tests/view/69209712acb6dbdf23d0836a LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 114786 W: 29097 L: 28976 D: 56713 Elo +0.37 Ptnml(0-2): 53, 11841, 33488, 11954, 57 closes https://github.com/official-stockfish/Stockfish/pull/6447 Bench: 2941767 see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Carlos Esparza
Date: Sun Nov 30 21:45:14 2025 +0100 Timestamp: 1764535514 Some more work on FullThreats::make_index [Passed STC](https://tests.stockfishchess.org/tests/live_elo/691fc321acb6dbdf23d07e4b): ``` LLR: 2.95 (-2.94,2.94) <0.00,2.00> Total: 215360 W: 55651 L: 55108 D: 104601 Elo +0.88 Ptnml(0-2): 520, 22399, 61290, 22960, 511 ``` This PR is on top of ces42's work so I'll rebase if that PR changes. Essentially, it comprises my adjustments to `make_index` that remained unmerged before threat inputs was finalized. The unsigned intermediate variables let us skip a bunch of useless sign extensions (because Square and Piece inherit from `int8_t`, and C/C++ semantics require narrow integers to be promoted to `int` before doing arithmetic on them). Additionally, by removing the special usage of `offsets[][64]` and `[65]` the indexing becomes more efficient. (This usage was a temporary hack from sscg anyway, so I think he'll like that it's gone.) Finally, the `sf_assume` condition was fixed so that it actually makes a difference to the compiler. The speedup is fairly nice locally (combining both ces42's and these changes): ``` Result of 100 runs ================== base (...kfish.master) = 1691982 +/- 1907 test (./stockfish ) = 1714349 +/- 1789 diff = +22367 +/- 2465 speedup = +0.0132 P(speedup > 0) = 1.0000 ``` closes https://github.com/official-stockfish/Stockfish/pull/6445 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Shawn Xu
Date: Sun Nov 30 21:43:54 2025 +0100 Timestamp: 1764535434 Simplify Incremental Updates Passed Non-regression STC: LLR: 3.03 (-2.94,2.94) <-1.75,0.25> Total: 277856 W: 71575 L: 71611 D: 134670 Elo -0.05 Ptnml(0-2): 842, 30719, 75836, 30695, 836 https://tests.stockfishchess.org/tests/view/69169dc17ca8781852331d76 Supersedes #6430 closes https://github.com/official-stockfish/Stockfish/pull/6434 No functional change see source |
| Windows x64 for Haswell CPUs Windows x64 for modern computers + AVX2 Windows x64 for modern computers Windows x64 + SSSE3 Windows x64 Linux x64 for Haswell CPUs Linux x64 for modern computers + AVX2 Linux x64 for modern computers Linux x64 + SSSE3 Linux x64 | Author: Shawn Xu
Date: Sun Nov 30 21:41:51 2025 +0100 Timestamp: 1764535311 Simplify Accumulator Updates Passed Non-regression STC: LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 146848 W: 37915 L: 37820 D: 71113 Elo +0.22 Ptnml(0-2): 415, 16159, 40186, 16244, 420 https://tests.stockfishchess.org/tests/view/691772217ca878185233202b closes https://github.com/official-stockfish/Stockfish/pull/6421 No functional change see source |