54b66a6e5f
de4238f92fbuild: consolidate reduced export checks (fanquake)012bdec1b7build: add building libconsensus to end-of-configure output (fanquake)8f360e349ebuild: remove ax_gcc_func_attribute macro (fanquake)f054a089ecbuild: remove AX_GCC_FUNC_ATTRIBUTE test for dllimport (fanquake)7cd0a69664build: test for __declspec(dllexport) in configure (fanquake)1624e17b54build: remove duplicate visibility attribute detection (fanquake) Pull request description: Darwin targets do not have a `protected` visibility function attribute, see [LLVM explanation](8e9a505139/clang/lib/Basic/Targets/OSTargets.h (L131)). This means that the `AX_GCC_FUNC_ATTRIBUTE` check for `visibility` fails: ```bash configure:24513: checking for __attribute__((visibility)) configure:24537: g++ -std=c++11 -o conftest -g -O2 -DHAVE_BUILD_INFO -D__STDC_FORMAT_MACROS -DMAC_OSX -DOBJC_OLD_DISPATCH_PROTOTYPES=0 -Wl,-headerpad_max_install_names conftest.cpp >&5 conftest.cpp:35:56: warning: target does not support 'protected' visibility; using 'default' [-Wunsupported-visibility] int foo_pro( void ) __attribute__((visibility("protected"))); ^ 1 warning generated. configure:24537: $? = 0 configure:24550: result: no ``` This leads to `EXPORT_SYMBOL` being [defined to nothing](f4de89edfa/src/script/bitcoinconsensus.h (L29)), as `HAVE_FUNC_ATTRIBUTE_VISIBILITY` is not defined, and when building with reduced exports, you end up with a libbitcoinconsensus.dylib that doesn't export any `_bitcoinconsensus_*` symbols. ```bash ➜ git:(master) nm -C src/.libs/libbitcoinconsensus.dylib | rg _bitcoinconsensus_ ➜ git:(master) ``` We do have a [second check](f4de89edfa/configure.ac (L882)) for the `visibility` attribute, which works for Darwin as it's only testing for default visibility, however the result of this check isn't used at all. It was added in #4725, along with the `--enable-reduce-exports` option, however when libbitcoinconsensus was added in #5235, it used the results of the added `AX_GCC_FUNC_ATTRIBUTE` calls. This PR removes our usage of the AX_GCC_FUNC_ATTRIBUTE macro entirely, in favour of our own checks in configure. This meant adding a check for `dllexport`, which I've tested as working with both [GCC](https://gcc.gnu.org/onlinedocs/gcc/Microsoft-Windows-Function-Attributes.html) and [Clang](https://releases.llvm.org/10.0.0/tools/clang/docs/AttributeReference.html#dllexport) when building for Windows. I haven't added an equivalent check for `dllimport`, as we weren't actually using the result of that check, we're just testing that `MSC_VER` was defined before using. With these changes building a libbitcoinconsensus with reduced exports, when targeting Darwin, works as expected: ```bash ./autogen.sh ./configure --disable-tests --disable-bench --with-utils=no --with-daemon=no --with-gui=no --disable-wallet --with-libs=yes --enable-reduce-exports make -j8 ... nm -C src/.libs/libbitcoinconsensus.dylib | rg _bitcoinconsensus_ 000000000000a340 T _bitcoinconsensus_verify_script 00000000000097e0 T _bitcoinconsensus_verify_script_with_amount 000000000000a3c0 T _bitcoinconsensus_version ``` ```python >>> import ctypes >>> consensus = ctypes.CDLL("src/.libs/libbitcoinconsensus.dylib") >>> print(consensus.bitcoinconsensus_version()) 1 >>> exit() ``` TODO: Modify a CI job to compile with --enable-reduce-exports and check for symbols in shared lib? ACKs for top commit: laanwj: Code review ACKde4238f92fTree-SHA512: d148f3c55d14dac6e9e5b718cc65bb557bcf6f663218d24bc9044b86281bd5dd3d931ebea79c336a58e8ed50d683218c0a9e75494f2267b91097665043e252ae
Bitcoin Core integration/staging tree
What is Bitcoin?
Bitcoin is an experimental digital currency that enables instant payments to anyone, anywhere in the world. Bitcoin uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Core is the name of open source software which enables the use of this currency.
For more information, as well as an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/, or read the original whitepaper.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/licenses/MIT.
Development Process
The master branch is regularly built (see doc/build-*.md for instructions) and tested, but it is not guaranteed to be
completely stable. Tags are created
regularly from release branches to indicate new official, stable release versions of Bitcoin Core.
The https://github.com/bitcoin-core/gui repository is used exclusively for the development of the GUI. Its master branch is identical in all monotree repositories. Release branches and tags do not exist, so please do not fork that repository unless it is for development reasons.
The contribution workflow is described in CONTRIBUTING.md and useful hints for developers can be found in doc/developer-notes.md.
Testing
Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Automated Testing
Developers are strongly encouraged to write unit tests for new code, and to
submit new unit tests for old code. Unit tests can be compiled and run
(assuming they weren't disabled in configure) with: make check. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
in Python, that are run automatically on the build server.
These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The CI (Continuous Integration) systems make sure that every pull request is built for Windows, Linux, and macOS, and that unit/sanity tests are run automatically.
Manual Quality Assurance (QA) Testing
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translations
Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.
Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.
Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.
Translators should also subscribe to the mailing list.