commit | de4a57cb21a19179d7be830967e642b868a05a91 | [log] [tgz] |
---|---|---|
author | Louis Dionne <[email protected]> | Mon Jun 27 19:53:41 2022 |
committer | Louis Dionne <[email protected]> | Tue Jun 28 02:18:19 2022 |
tree | 808a675b178dcaddeeed480720bb2ebfdb1da59a | |
parent | ea1b86127814aff54b2ab821db060865af920437 [diff] |
[libc++] Re-add transitive includes that had been removed since LLVM 14 This commit re-adds transitive includes that had been removed by 4cd04d1687f1, c36870c8e79c, a83f4b9cda57, 1458458b558d, 2e2f3158c604, and 489637e66dd3. This should cover almost all the includes that had been removed since LLVM 14 and that would contribute to breaking user code when releasing LLVM 15. It is possible to disable the inclusion of these headers by defining _LIBCPP_REMOVE_TRANSITIVE_INCLUDES. The intent is that vendors will enable that macro and start fixing downstream issues immediately. We can then remove the macro (and the transitive includes) by default in a future release. That way, we will break users only once by removing transitive includes in bulk instead of doing it bit by bit a every release, which is more disruptive for users. Note 1: The set of headers to re-add was found by re-generating the transitive include test on a checkout of release/14.x, which provided the list of all transitive includes we used to provide. Note 2: Several includes of <vector>, <optional>, <array> and <unordered_map> have been added in this commit. These transitive inclusions were added when we implemented boyer_moore_searcher in <functional>. Note 3: This is a best effort patch to try and resolve downstream breakage caused since branching LLVM 14. I wasn't able to perfectly mirror transitive includes in LLVM 14 for a few headers, so I added a release note explaining it. To summarize, adding boyer_moore_searcher created a bunch of circular dependencies, so we have to break backwards compatibility in a few cases. Differential Revision: https://reviews.llvm.org/D128661
This directory and its sub-directories contain the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.
The README briefly describes how to get started with building LLVM. For more information on how to contribute to the LLVM project, please take a look at the Contributing to LLVM guide.
Taken from here.
Welcome to the LLVM project!
The LLVM project has multiple components. The core of the project is itself called “LLVM”. This contains all of the tools, libraries, and header files needed to process intermediate representations and convert them into object files. Tools include an assembler, disassembler, bitcode analyzer, and bitcode optimizer. It also contains basic regression tests.
C-like languages use the Clang frontend. This component compiles C, C++, Objective-C, and Objective-C++ code into LLVM bitcode -- and from there into object files, using LLVM.
Other components include: the libc++ C++ standard library, the LLD linker, and more.
The LLVM Getting Started documentation may be out of date. The Clang Getting Started page might have more accurate information.
This is an example work-flow and configuration to get and build the LLVM source:
Checkout LLVM (including related sub-projects like Clang):
git clone https://github.com/llvm/llvm-project.git
Or, on windows, git clone --config core.autocrlf=false https://github.com/llvm/llvm-project.git
Configure and build LLVM and Clang:
cd llvm-project
cmake -S llvm -B build -G <generator> [options]
Some common build system generators are:
Ninja
--- for generating Ninja build files. Most llvm developers use Ninja.Unix Makefiles
--- for generating make-compatible parallel makefiles.Visual Studio
--- for generating Visual Studio projects and solutions.Xcode
--- for generating Xcode projects.Some common options:
-DLLVM_ENABLE_PROJECTS='...'
and -DLLVM_ENABLE_RUNTIMES='...'
--- semicolon-separated list of the LLVM sub-projects and runtimes you'd like to additionally build. LLVM_ENABLE_PROJECTS
can include any of: clang, clang-tools-extra, cross-project-tests, flang, libc, libclc, lld, lldb, mlir, openmp, polly, or pstl. LLVM_ENABLE_RUNTIMES
can include any of libcxx, libcxxabi, libunwind, compiler-rt, libc or openmp. Some runtime projects can be specified either in LLVM_ENABLE_PROJECTS
or in LLVM_ENABLE_RUNTIMES
.
For example, to build LLVM, Clang, libcxx, and libcxxabi, use -DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi"
.
-DCMAKE_INSTALL_PREFIX=directory
--- Specify for directory the full path name of where you want the LLVM tools and libraries to be installed (default /usr/local
). Be careful if you install runtime libraries: if your system uses those provided by LLVM (like libc++ or libc++abi), you must not overwrite your system's copy of those libraries, since that could render your system unusable. In general, using something like /usr
is not advised, but /usr/local
is fine.
-DCMAKE_BUILD_TYPE=type
--- Valid options for type are Debug, Release, RelWithDebInfo, and MinSizeRel. Default is Debug.
-DLLVM_ENABLE_ASSERTIONS=On
--- Compile with assertion checks enabled (default is Yes for Debug builds, No for all other build types).
cmake --build build [-- [options] <target>]
or your build system specified above directly.
The default target (i.e. ninja
or make
) will build all of LLVM.
The check-all
target (i.e. ninja check-all
) will run the regression tests to ensure everything is in working order.
CMake will generate targets for each tool and library, and most LLVM sub-projects generate their own check-<project>
target.
Running a serial build will be slow. To improve speed, try running a parallel build. That's done by default in Ninja; for make
, use the option -j NNN
, where NNN
is the number of parallel jobs to run. In most cases, you get the best performance if you specify the number of CPU threads you have. On some Unix systems, you can specify this with -j$(nproc)
.
For more information see CMake.
Consult the Getting Started with LLVM page for detailed information on configuring and compiling LLVM. You can visit Directory Layout to learn about the layout of the source code tree.
Join LLVM Discourse forums, discord chat or #llvm IRC channel on OFTC.
The LLVM project has adopted a code of conduct for participants to all modes of communication within the project.