Lines Matching +full:llvm +full:- +full:project
12 LLVM, and contributing it back to the LLVM project.
16 should actually submit to the LLVM project. For your first real change to LLVM,
19 We'll be making a change to Clang, but the steps for other parts of LLVM are the same.
21 steps like building LLVM, running the tests, and code review. This is
26 - know how to use an editor,
28 - have basic C++ knowledge,
30 - know how to install software on your system,
32 - are comfortable with the command line,
34 - have basic knowledge of git.
38 -----------------------
45 $ clang -c -Wall ~/test.cc
46 test.cc:1:12: warning: all paths through this function will call itself [-Winfinite-recursion]
53 test.cc:1:12: warning: to understand recursion, you must first understand recursion [-Winfinite-recursion]
57 ------------
61 - git: to check out the LLVM source code,
63 - a C++ compiler: to compile LLVM source code. You'll want `a recent
66 - CMake: used to configure how LLVM should be built on your system,
68 - ninja: runs the C++ compiler to (re)build specific parts of LLVM,
70 - python: to run the LLVM tests.
76 $ sudo apt-get install git clang cmake ninja-build python
79 Building LLVM
84 --------
87 Github <https://github.com/llvm/llvm-project>`__ in one large repository
94 $ git clone https://github.com/llvm/llvm-project.git
96 This will create a directory "llvm-project" with all of the source
97 code. (Checking out anonymously is OK - pushing commits uses a different
101 ------------------------
106 - explicit choices you make (is this a debug build?)
108 - settings detected from your system (where are libraries installed?)
110 - project structure (which files are part of 'clang'?)
112 First, create a directory to build in. Usually, this is ``llvm-project/build``.
116 $ mkdir llvm-project/build
117 $ cd llvm-project/build
123 $ cmake -G Ninja ../llvm -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_PROJECTS=clang
132 Build files have been written to: /path/llvm-project/build
138 - **-G Ninja**: Tells CMake that we're going to use ninja to build, and to create
141 - **../llvm**: this is the path to the source of the "main" LLVM
142 project
144 - The two **-D** flags set CMake variables, which override
145 CMake/project defaults:
147 - **CMAKE_BUILD_TYPE=Release**: build in optimized mode, which is
157 - **LLVM_ENABLE_PROJECTS=clang**: this lists the LLVM subprojects
158 you are interested in building, in addition to LLVM itself. Multiple
162 Finally, create a symlink (or copy) of ``llvm-project/build/compile-commands.json``
163 into ``llvm-project/``:
167 $ ln -s build/compile_commands.json ../
170 tools like clang-tidy, clang-query, and clangd to work in your source
175 --------------
186 The first time we build will be very slow - Clang + LLVM is a lot of
193 $ bin/clang --version
199 $ ninja check-clang
201 This is a common pattern in LLVM: check-llvm is all the checks for the core of
202 LLVM, other projects have targets like ``check-lldb``, ``check-flang`` and so on.
210 ----------
220 printed by Clang. ``*.td`` files define tables - in this case it's a list
233 ----------
241 $ bin/clang -c -Wall ~/test.cc
242 test.cc:1:12: warning: in order to understand recursion, you must first understand recursion [-Winfinite-recursion]
248 $ ninja check-clang
258 Clang :: SemaCXX/warn-infinite-recursion.cpp
269 $ vi ../clang/test/SemaCXX/warn-infinite-recursion.cpp
271 Everywhere we see ``// expected-warning{{call itself}}`` (or something similar
273 ``// expected-warning{{to understand recursion}}``.
276 iterate on a change! Instead, let's find a way to re-run just the
277 specific test. There are two main types of tests in LLVM:
279 - **lit tests** (e.g. ``SemaCXX/warn-infinite-recursion.cpp``).
281 These are fancy shell scripts that run command-line tools and verify the
283 ``clang/**test**/FixIt/dereference-addressof.c``. Re-run like this:
287 $ bin/llvm-lit -v ../clang/test/SemaCXX/warn-infinite-recursion.cpp
289 - **unit tests** (e.g. ``ToolingTests/ReplacementTest.CanDeleteAllText``)
291 These are C++ programs that call LLVM functions and verify the results.
292 They live in suites like ToolingTests. Re-run like this:
296 $ ninja ToolingTests && tools/clang/unittests/Tooling/ToolingTests --gtest_filter=ReplacementTest.CanDeleteAllText
300 --------------
311 $ git checkout -b myfirstpatch
312 $ git commit -am "[clang][Diagnostic] Clarify -Winfinite-recursion message"
323 $ git log --oneline ../clang/
325 Or using GitHub, for example https://github.com/llvm/llvm-project/commits/main/clang.
334 -----------------------------
336 LLVM code reviews happen through pull-request on GitHub, see the
337 :ref:`GitHub <github-reviews>` documentation for how to open
338 a pull-request on GitHub.
341 ------------------
343 Changes can be reviewed by anyone in the LLVM community. For larger and more
345 reviewer has experience with the area of LLVM and knows the design goals
349 Our GitHub bot will also tag and notify various "teams" around LLVM. The
354 --------------
356 When you open a pull-request, some automation will add a comment and
357 notify different members of the sub-projects depending on the parts you have
377 your branch with more commits and push to your GitHub fork of ``llvm-project``.
385 -------------------
387 In order to make LLVM a long-term sustainable effort, code needs to be
390 and push-back on design decisions that do not fit well within the
391 overall architecture of the project.
395 - be kind, and expect reviewers to be kind in return - LLVM has a
396 :ref:`Code of Conduct <LLVM Community Code of Conduct>`
399 - be patient - understanding how a new feature fits into the
400 architecture of the project is often a time consuming effort, and
404 - if you can't agree, generally the best way is to do what the reviewer
412 ------------------------
424 ---------------
433 The pull-request will be closed and you will be notified by GitHub.
436 ---------------------
438 Once you've contributed a handful of patches to LLVM, start to think
441 - you've landed 3-5 patches of larger scope than "fix a typo"
443 - you'd be willing to review changes that are closely related to yours
445 - you'd like to keep contributing to LLVM.
451 ----------------
465 The "console" view at http://lab.llvm.org/buildbot/#/console displays results
497 -------
500 This is a normal part of :ref:`LLVM development <revert_policy>`,
507 the `GitHub interface <https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/incorporating-changes-from-a-pull-request/reverting-a-pull-request>`__.
514 LLVM Project.
516 If some details are still unclear, do not worry. The LLVM Project's process does
517 differ from what you may be used to elsewhere on GitHub. Within the project
518 the expectations of different sub-projects may vary too.