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The code behind the network, with room to understand it.

Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

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1Bitcoin Core version 0.13.0 is now available from:
2
3  <https://bitcoin.org/bin/bitcoin-core-0.13.0/>
4
5This is a new major version release, including new features, various bugfixes
6and performance improvements, as well as updated translations.
7
8Please report bugs using the issue tracker at github:
9
10  <https://github.com/bitcoin/bitcoin/issues>
11
12To receive security and update notifications, please subscribe to:
13
14  <https://bitcoincore.org/en/list/announcements/join/>
15
16Compatibility
17==============
18
19Microsoft ended support for Windows XP on [April 8th, 2014](https://www.microsoft.com/en-us/WindowsForBusiness/end-of-xp-support),
20an OS initially released in 2001. This means that not even critical security
21updates will be released anymore. Without security updates, using a bitcoin
22wallet on a XP machine is irresponsible at least.
23
24In addition to that, with 0.12.x there have been varied reports of Bitcoin Core
25randomly crashing on Windows XP. It is [not clear](https://github.com/bitcoin/bitcoin/issues/7681#issuecomment-217439891)
26what the source of these crashes is, but it is likely that upstream
27libraries such as Qt are no longer being tested on XP.
28
29We do not have time nor resources to provide support for an OS that is
30end-of-life. From 0.13.0 on, Windows XP is no longer supported. Users are
31suggested to upgrade to a newer verion of Windows, or install an alternative OS
32that is supported.
33
34No attempt is made to prevent installing or running the software on Windows XP,
35you can still do so at your own risk, but do not expect it to work: do not
36report issues about Windows XP to the issue tracker.
37
38Notable changes
39===============
40
41Database cache memory increased
42--------------------------------
43
44As a result of growth of the UTXO set, performance with the prior default
45database cache of 100 MiB has suffered.
46For this reason the default was changed to 300 MiB in this release.
47
48For nodes on low-memory systems, the database cache can be changed back to
49100 MiB (or to another value) by either:
50
51- Adding `dbcache=100` in bitcoin.conf
52- Changing it in the GUI under `Options → Size of database cache`
53
54Note that the database cache setting has the most performance impact
55during initial sync of a node, and when catching up after downtime.
56
57
58bitcoin-cli: arguments privacy
59------------------------------
60
61The RPC command line client gained a new argument, `-stdin`
62to read extra arguments from standard input, one per line until EOF/Ctrl-D.
63For example:
64
65    $ src/bitcoin-cli -stdin walletpassphrase
66    mysecretcode
67    120
68    ..... press Ctrl-D here to end input
69    $
70
71It is recommended to use this for sensitive information such as wallet
72passphrases, as command-line arguments can usually be read from the process
73table by any user on the system.
74
75
76C++11 and Python 3
77------------------
78
79Various code modernizations have been done. The Bitcoin Core code base has
80started using C++11. This means that a C++11-capable compiler is now needed for
81building. Effectively this means GCC 4.7 or higher, or Clang 3.3 or higher.
82
83When cross-compiling for a target that doesn't have C++11 libraries, configure with
84`./configure --enable-glibc-back-compat ... LDFLAGS=-static-libstdc++`.
85
86For running the functional tests in `qa/rpc-tests`, Python3.4 or higher is now
87required.
88
89
90Linux ARM builds
91----------------
92
93Due to popular request, Linux ARM builds have been added to the uploaded
94executables.
95
96The following extra files can be found in the download directory or torrent:
97
98- `bitcoin-${VERSION}-arm-linux-gnueabihf.tar.gz`: Linux binaries targeting
99  the 32-bit ARMv7-A architecture.
100- `bitcoin-${VERSION}-aarch64-linux-gnu.tar.gz`: Linux binaries targeting
101  the 64-bit ARMv8-A architecture.
102
103ARM builds are still experimental. If you have problems on a certain device or
104Linux distribution combination please report them on the bug tracker, it may be
105possible to resolve them. Note that the device you use must be (backward)
106compatible with the architecture targeted by the binary that you use.
107For example, a Raspberry Pi 2 Model B or Raspberry Pi 3 Model B (in its 32-bit
108execution state) device, can run the 32-bit ARMv7-A targeted binary. However,
109no model of Raspberry Pi 1 device can run either binary because they are all
110ARMv6 architecture devices that are not compatible with ARMv7-A or ARMv8-A.
111
112Note that Android is not considered ARM Linux in this context. The executables
113are not expected to work out of the box on Android.
114
115
116Compact Block support (BIP 152)
117-------------------------------
118
119Support for block relay using the Compact Blocks protocol has been implemented
120in PR 8068.
121
122The primary goal is reducing the bandwidth spikes at relay time, though in many
123cases it also reduces propagation delay. It is automatically enabled between
124compatible peers.
125[BIP 152](https://github.com/bitcoin/bips/blob/master/bip-0152.mediawiki)
126
127As a side-effect, ordinary non-mining nodes will download and upload blocks
128faster if those blocks were produced by miners using similar transaction
129filtering policies. This means that a miner who produces a block with many
130transactions discouraged by your node will be relayed slower than one with
131only transactions already in your memory pool. The overall effect of such
132relay differences on the network may result in blocks which include widely-
133discouraged transactions losing a stale block race, and therefore miners may
134wish to configure their node to take common relay policies into consideration.
135
136
137Hierarchical Deterministic Key Generation
138-----------------------------------------
139Newly created wallets will use hierarchical deterministic key generation
140according to BIP32 (keypath m/0'/0'/k').
141Existing wallets will still use traditional key generation.
142
143Backups of HD wallets, regardless of when they have been created, can
144therefore be used to re-generate all possible private keys, even the
145ones which haven't already been generated during the time of the backup.
146**Attention:** Encrypting the wallet will create a new seed which requires
147a new backup!
148
149Wallet dumps (created using the `dumpwallet` RPC) will contain the deterministic
150seed. This is expected to allow future versions to import the seed and all
151associated funds, but this is not yet implemented.
152
153HD key generation for new wallets can be disabled by `-usehd=0`. Keep in
154mind that this flag only has affect on newly created wallets.
155You can't disable HD key generation once you have created a HD wallet.
156
157There is no distinction between internal (change) and external keys.
158
159HD wallets are incompatible with older versions of Bitcoin Core.
160
161[Pull request](https://github.com/bitcoin/bitcoin/pull/8035/files), [BIP 32](https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki)
162
163
164Segregated Witness
165------------------
166
167The code preparations for Segregated Witness ("segwit"), as described in [BIP
168141](https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki), [BIP
169143](https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki), [BIP
170144](https://github.com/bitcoin/bips/blob/master/bip-0144.mediawiki), and [BIP
171145](https://github.com/bitcoin/bips/blob/master/bip-0145.mediawiki) are
172finished and included in this release.  However, BIP 141 does not yet specify
173activation parameters on mainnet, and so this release does not support segwit
174use on mainnet.  Testnet use is supported, and after BIP 141 is updated with
175proposed parameters, a future release of Bitcoin Core is expected that
176implements those parameters for mainnet.
177
178Furthermore, because segwit activation is not yet specified for mainnet,
179version 0.13.0 will behave similarly as other pre-segwit releases even after a
180future activation of BIP 141 on the network.  Upgrading from 0.13.0 will be
181required in order to utilize segwit-related features on mainnet (such as signal
182BIP 141 activation, mine segwit blocks, fully validate segwit blocks, relay
183segwit blocks to other segwit nodes, and use segwit transactions in the
184wallet, etc).
185
186
187Mining transaction selection ("Child Pays For Parent")
188------------------------------------------------------
189
190The mining transaction selection algorithm has been replaced with an algorithm
191that selects transactions based on their feerate inclusive of unconfirmed
192ancestor transactions.  This means that a low-fee transaction can become more
193likely to be selected if a high-fee transaction that spends its outputs is
194relayed.
195
196With this change, the `-blockminsize` command line option has been removed.
197
198The command line option `-blockmaxsize` remains an option to specify the
199maximum number of serialized bytes in a generated block.  In addition, the new
200command line option `-blockmaxweight` has been added, which specifies the
201maximum "block weight" of a generated block, as defined by [BIP 141 (Segregated
202Witness)] (https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki).
203
204In preparation for Segregated Witness, the mining algorithm has been modified
205to optimize transaction selection for a given block weight, rather than a given
206number of serialized bytes in a block.  In this release, transaction selection
207is unaffected by this distinction (as BIP 141 activation is not supported on
208mainnet in this release, see above), but in future releases and after BIP 141
209activation, these calculations would be expected to differ.
210
211For optimal runtime performance, miners using this release should specify
212`-blockmaxweight` on the command line, and not specify `-blockmaxsize`.
213Additionally (or only) specifying `-blockmaxsize`, or relying on default
214settings for both, may result in performance degradation, as the logic to
215support `-blockmaxsize` performs additional computation to ensure that
216constraint is met.  (Note that for mainnet, in this release, the equivalent
217parameter for `-blockmaxweight` would be four times the desired
218`-blockmaxsize`.  See [BIP 141]
219(https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki) for additional
220details.)
221
222In the future, the `-blockmaxsize` option may be removed, as block creation is
223no longer optimized for this metric.  Feedback is requested on whether to
224deprecate or keep this command line option in future releases.
225
226
227Reindexing changes
228------------------
229
230In earlier versions, reindexing did validation while reading through the block
231files on disk. These two have now been split up, so that all blocks are known
232before validation starts. This was necessary to make certain optimizations that
233are available during normal synchronizations also available during reindexing.
234
235The two phases are distinct in the Bitcoin-Qt GUI. During the first one,
236"Reindexing blocks on disk" is shown. During the second (slower) one,
237"Processing blocks on disk" is shown.
238
239It is possible to only redo validation now, without rebuilding the block index,
240using the command line option `-reindex-chainstate` (in addition to
241`-reindex` which does both). This new option is useful when the blocks on disk
242are assumed to be fine, but the chainstate is still corrupted. It is also
243useful for benchmarks.
244
245
246Removal of internal miner
247--------------------------
248
249As CPU mining has been useless for a long time, the internal miner has been
250removed in this release, and replaced with a simpler implementation for the

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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