This is an archive of the discontinued LLVM Phabricator instance.

Differential D112724

Officially deprecate LLVM_ENABLE_PROJECTS for libc++, libc++abi and libunwind
ClosedPublic

Authored by ldionne on Oct 28 2021, 8:23 AM.

Details

Reviewers
awarzynski
jdoerfert
Commits
rG2912f53699da: Officially deprecate LLVM_ENABLE_PROJECTS for libc++, libc++abi and libunwind
Summary

This updates the LLVM wide documentation for building LLVM and the runtimes
and adds a CMake warning when folks specify libcxx, libcxxabi or libunwind
in LLVM_ENABLE_PROJECTS, pointing them to the updated instructions for
building the runtimes.

Diff Detail

Event Timeline

ldionne created this revision.Oct 28 2021, 8:23 AM
Herald added a subscriber: mgorny. · View Herald TranscriptOct 28 2021, 8:23 AM
ldionne requested review of this revision.Oct 28 2021, 8:23 AM
Herald added a reviewer: jdoerfert. · View Herald TranscriptOct 28 2021, 8:23 AM
Herald added a project: Restricted Project. · View Herald Transcript
Herald added subscribers: llvm-commits, sstefan1. · View Herald Transcript
Harbormaster completed remote builds in B131209: Diff 383042.Oct 28 2021, 8:59 AM
awarzynski accepted this revision.Oct 29 2021, 4:09 AM

This has been a source of confusion for many people - many thanks for clarifying this!

LGTM

This revision is now accepted and ready to land.Oct 29 2021, 4:09 AM
This revision was landed with ongoing or failed builds.Oct 29 2021, 5:53 AM
Closed by commit rG2912f53699da: Officially deprecate LLVM_ENABLE_PROJECTS for libc++, libc++abi and libunwind (authored by ldionne). · Explain Why
This revision was automatically updated to reflect the committed changes.
ldionne added a commit: rG2912f53699da: Officially deprecate LLVM_ENABLE_PROJECTS for libc++, libc++abi and libunwind.
thakis added a subscriber: thakis.Feb 7 2022, 10:05 AM
thakis added inline comments.
llvm/CMakeLists.txt
67

libcxx libcxxabi libunwind are still part of LLVM_ALL_PROJECTS and...

87

...this is below the warning you added. So if you say LLVM_ALL_PROJECTS=all you still get the old behavior, without a warning. Is that intentional?

(Doesn't affect us, just happened to notice it while reading this file.)

ldionne added inline comments.Feb 7 2022, 11:23 AM
llvm/CMakeLists.txt
87

I think it was intentional -- I didn't intend to issue a warning for folks who use all if they are not using libcxx, libcxxabi or libunwind explicitly. I think the next step would be to remove libcxx, libcxxabi` and libunwind from all, and to make this warning into an error since we don't support this anymore as of the branch point.

MaskRay mentioned this in D107799: [CMake] Enable LLVM_ENABLE_PER_TARGET_RUNTIME_DIR by default on Linux.Jun 3 2022, 1:09 AM
MaskRay mentioned this in rG311f78396023: [CMake] Enable LLVM_ENABLE_PER_TARGET_RUNTIME_DIR by default on Linux.Jun 7 2022, 9:22 PM
fdeazeve mentioned this in rZORGf519bdc806c3: [lldb-cmake-matrix] Use RUNTIME option for libcxx/libcxxabi.Aug 16 2022, 4:57 AM
fdeazeve mentioned this in rZORG725e5efb0069: [lldb-cmake-matrix] Use RUNTIME option for libcxx/libcxxabi.Aug 16 2022, 11:59 AM
Ericson2314 mentioned this in D132324: [RFC] Remove support for building libc++ with `LLVM_ENABLE_PROJECTS`.Aug 20 2022, 6:54 PM
Ericson2314 mentioned this in rG176db3b3ab25: [RFC] Remove support for building C++ with `LLVM_ENABLE_PROJECTS`.Aug 21 2022, 5:11 AM
DoyleLi mentioned this in D158142: Improved InformativeMailNotifier..Aug 16 2023, 10:20 PM

Revision Contents

PathSize
llvm/
6 lines
docs/
11 lines
5 lines

Diff 383325

llvm/CMakeLists.txt

Show First 20 Lines • Show All 58 Lines • ▼ Show 20 Linesif (NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
message(STATUS "No build type selected, default to Debug") message(STATUS "No build type selected, default to Debug")
set(CMAKE_BUILD_TYPE "Debug" CACHE STRING "Build type (default Debug)" FORCE) set(CMAKE_BUILD_TYPE "Debug" CACHE STRING "Build type (default Debug)" FORCE)
endif() endif()
# Side-by-side subprojects layout: automatically set the # Side-by-side subprojects layout: automatically set the
# LLVM_EXTERNAL_${project}_SOURCE_DIR using LLVM_ALL_PROJECTS # LLVM_EXTERNAL_${project}_SOURCE_DIR using LLVM_ALL_PROJECTS
# This allows an easy way of setting up a build directory for llvm and another # This allows an easy way of setting up a build directory for llvm and another
# one for llvm+clang+... using the same sources. # one for llvm+clang+... using the same sources.
set(LLVM_ALL_PROJECTS "clang;clang-tools-extra;compiler-rt;cross-project-tests;libc;libclc;libcxx;libcxxabi;libunwind;lld;lldb;mlir;openmp;polly;pstl") set(LLVM_ALL_PROJECTS "clang;clang-tools-extra;compiler-rt;cross-project-tests;libc;libclc;libcxx;libcxxabi;libunwind;lld;lldb;mlir;openmp;polly;pstl")
thakisUnsubmitted
Not Done
ReplyInline Actions

libcxx libcxxabi libunwind are still part of LLVM_ALL_PROJECTS and...

thakis: libcxx libcxxabi libunwind are still part of LLVM_ALL_PROJECTS and...
# The flang project is not yet part of "all" projects (see C++ requirements) # The flang project is not yet part of "all" projects (see C++ requirements)
set(LLVM_EXTRA_PROJECTS "flang") set(LLVM_EXTRA_PROJECTS "flang")
# List of all known projects in the mono repo # List of all known projects in the mono repo
set(LLVM_KNOWN_PROJECTS "${LLVM_ALL_PROJECTS};${LLVM_EXTRA_PROJECTS}") set(LLVM_KNOWN_PROJECTS "${LLVM_ALL_PROJECTS};${LLVM_EXTRA_PROJECTS}")
set(LLVM_ENABLE_PROJECTS "" CACHE STRING set(LLVM_ENABLE_PROJECTS "" CACHE STRING
"Semicolon-separated list of projects to build (${LLVM_KNOWN_PROJECTS}), or \"all\".") "Semicolon-separated list of projects to build (${LLVM_KNOWN_PROJECTS}), or \"all\".")
foreach(proj ${LLVM_ENABLE_PROJECTS}) foreach(proj ${LLVM_ENABLE_PROJECTS})
if (NOT proj STREQUAL "all" AND NOT proj STREQUAL "llvm" AND NOT "${proj}" IN_LIST LLVM_KNOWN_PROJECTS) if (NOT proj STREQUAL "all" AND NOT proj STREQUAL "llvm" AND NOT "${proj}" IN_LIST LLVM_KNOWN_PROJECTS)
MESSAGE(FATAL_ERROR "${proj} isn't a known project: ${LLVM_KNOWN_PROJECTS}") MESSAGE(FATAL_ERROR "${proj} isn't a known project: ${LLVM_KNOWN_PROJECTS}")
endif() endif()
endforeach() endforeach()
foreach(proj "libcxx" "libcxxabi" "libunwind")
if (${proj} IN_LIST LLVM_ENABLE_PROJECTS)
message(WARNING "Using LLVM_ENABLE_PROJECTS=${proj} is deprecated now, please use -DLLVM_ENABLE_RUNTIMES=${proj} or "
"see the instructions at https://libcxx.llvm.org/BuildingLibcxx.html for building the runtimes.")
endif()
endforeach()
if( LLVM_ENABLE_PROJECTS STREQUAL "all" ) if( LLVM_ENABLE_PROJECTS STREQUAL "all" )
set( LLVM_ENABLE_PROJECTS ${LLVM_ALL_PROJECTS}) set( LLVM_ENABLE_PROJECTS ${LLVM_ALL_PROJECTS})
thakisUnsubmitted
Not Done
ReplyInline Actions

...this is below the warning you added. So if you say LLVM_ALL_PROJECTS=all you still get the old behavior, without a warning. Is that intentional?

(Doesn't affect us, just happened to notice it while reading this file.)

thakis: ...this is below the warning you added. So if you say LLVM_ALL_PROJECTS=all you still get the…
ldionneAuthorUnsubmitted
Done
ReplyInline Actions

I think it was intentional -- I didn't intend to issue a warning for folks who use all if they are not using libcxx, libcxxabi or libunwind explicitly. I think the next step would be to remove libcxx, libcxxabi` and libunwind from all, and to make this warning into an error since we don't support this anymore as of the branch point.

ldionne: I think it was intentional -- I didn't intend to issue a warning for folks who use `all` if…
endif() endif()
if ("flang" IN_LIST LLVM_ENABLE_PROJECTS) if ("flang" IN_LIST LLVM_ENABLE_PROJECTS)
if (NOT "mlir" IN_LIST LLVM_ENABLE_PROJECTS) if (NOT "mlir" IN_LIST LLVM_ENABLE_PROJECTS)
message(STATUS "Enabling MLIR as a dependency to flang") message(STATUS "Enabling MLIR as a dependency to flang")
list(APPEND LLVM_ENABLE_PROJECTS "mlir") list(APPEND LLVM_ENABLE_PROJECTS "mlir")
endif() endif()
▲ Show 20 Lines • Show All 1,103 Lines • Show Last 20 Lines

llvm/docs/CMake.rst

Show First 20 Lines • Show All 479 Lines • ▼ Show 20 Lines**LLVM_ENABLE_PEDANTIC**:BOOL
possible. Defaults to ON. possible. Defaults to ON.
**LLVM_ENABLE_PIC**:BOOL **LLVM_ENABLE_PIC**:BOOL
Add the ``-fPIC`` flag to the compiler command-line, if the compiler supports Add the ``-fPIC`` flag to the compiler command-line, if the compiler supports
this flag. Some systems, like Windows, do not need this flag. Defaults to ON. this flag. Some systems, like Windows, do not need this flag. Defaults to ON.
**LLVM_ENABLE_PROJECTS**:STRING **LLVM_ENABLE_PROJECTS**:STRING
Semicolon-separated list of projects to build, or *all* for building all Semicolon-separated list of projects to build, or *all* for building all
(clang, libcxx, libcxxabi, lldb, compiler-rt, lld, polly, etc) projects. (clang, lldb, compiler-rt, lld, polly, etc) projects. This flag assumes
This flag assumes that projects are checked out side-by-side and not nested, that projects are checked out side-by-side and not nested, i.e. clang
i.e. clang needs to be in parallel of llvm instead of nested in `llvm/tools`. needs to be in parallel of llvm instead of nested in `llvm/tools`.
This feature allows to have one build for only LLVM and another for clang+llvm This feature allows to have one build for only LLVM and another for clang+llvm
using the same source checkout. using the same source checkout.
The full list is: The full list is:
``clang;clang-tools-extra;compiler-rt;cross-project-tests;libc;libclc;libcxx;libcxxabi;libunwind;lld;lldb;openmp;polly;pstl`` ``clang;clang-tools-extra;compiler-rt;cross-project-tests;libc;libclc;lld;lldb;openmp;polly;pstl``
**LLVM_ENABLE_RUNTIMES**:STRING **LLVM_ENABLE_RUNTIMES**:STRING
Build libc++, libc++abi or other projects using that a just-built compiler. Build libc++, libc++abi or other projects using that a just-built compiler.
This is the correct way to build libc++ when putting together a toolchain. This is the correct way to build libc++ when putting together a toolchain.
It will build the builtins separately from the other runtimes to preserve It will build the builtins separately from the other runtimes to preserve
correct dependency ordering. correct dependency ordering. If you want to build the runtimes using a system
compiler, see the `libc++ documentation <https://libcxx.llvm.org/BuildingLibcxx.html>`_.
Note: the list should not have duplicates with `LLVM_ENABLE_PROJECTS`. Note: the list should not have duplicates with `LLVM_ENABLE_PROJECTS`.
The full list is: The full list is:
``compiler-rt;libc;libcxx;libcxxabi;libunwind;openmp`` ``compiler-rt;libc;libcxx;libcxxabi;libunwind;openmp``
To enable all of them, use: To enable all of them, use:
``LLVM_ENABLE_RUNTIMES=all`` ``LLVM_ENABLE_RUNTIMES=all``
**LLVM_ENABLE_RTTI**:BOOL **LLVM_ENABLE_RTTI**:BOOL
▲ Show 20 Lines • Show All 493 Lines • Show Last 20 Lines

llvm/docs/GettingStarted.rst

Show First 20 Lines • Show All 57 Lines • ▼ Show 20 Lines * ``cmake -G <generator> [options] ../llvm``
* ``Visual Studio`` --- for generating Visual Studio projects and * ``Visual Studio`` --- for generating Visual Studio projects and
solutions. solutions.
* ``Xcode`` --- for generating Xcode projects. * ``Xcode`` --- for generating Xcode projects.
Some Common options: Some Common options:
* ``-DLLVM_ENABLE_PROJECTS='...'`` --- semicolon-separated list of the LLVM * ``-DLLVM_ENABLE_PROJECTS='...'`` --- semicolon-separated list of the LLVM
subprojects you'd like to additionally build. Can include any of: clang, subprojects you'd like to additionally build. Can include any of: clang,
clang-tools-extra, libcxx, libcxxabi, libunwind, lldb, compiler-rt, lld, clang-tools-extra, lldb, compiler-rt, lld, polly, or cross-project-tests.
polly, or cross-project-tests.
For example, to build LLVM, Clang, libcxx, and libcxxabi, use For example, to build LLVM, Clang, libcxx, and libcxxabi, use
``-DLLVM_ENABLE_PROJECTS="clang;libcxx;libcxxabi"``. ``-DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi"``.
* ``-DCMAKE_INSTALL_PREFIX=directory`` --- Specify for *directory* the full * ``-DCMAKE_INSTALL_PREFIX=directory`` --- Specify for *directory* the full
pathname of where you want the LLVM tools and libraries to be installed pathname of where you want the LLVM tools and libraries to be installed
(default ``/usr/local``). (default ``/usr/local``).
* ``-DCMAKE_BUILD_TYPE=type`` --- Valid options for *type* are Debug, * ``-DCMAKE_BUILD_TYPE=type`` --- Valid options for *type* are Debug,
Release, RelWithDebInfo, and MinSizeRel. Default is Debug. Release, RelWithDebInfo, and MinSizeRel. Default is Debug.
▲ Show 20 Lines • Show All 1,168 Lines • Show Last 20 Lines