Skip to content

[llvm] Enable LLVM_LINK_LLVM_DYLIB by default on non-Windows platforms #138187

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 11 commits into
base: main
Choose a base branch
from
Open

[llvm] Enable LLVM_LINK_LLVM_DYLIB by default on non-Windows platforms #138187

Show file tree
Hide file tree
Changes from 10 commits
Commits
Show all changes
11 commits
Select commit Hold shift + click to select a range
7e23666
[llvm] Enable LLVM_LINK_LLVM_DYLIB by default on non-Windows platforms
rnk Apr 30, 2025
53c1338
Merge branch 'main' into llvm-dylib-default
rnk May 2, 2025
96fddd1
Merge branch 'main' into llvm-dylib-default
rnk Jun 25, 2025
1eb025c
Remove debug prints
rnk Jun 25, 2025
788bd48
Disable linking the dylib from TestingSupport, it only uses Support
rnk Jun 26, 2025
2f1529f
Add release notes
rnk Jun 26, 2025
5904206
Remove bolt unittest dep on LLVMTestingSupport to fix link
rnk Jun 26, 2025
2fd375e
Merge branch 'main' into llvm-dylib-default
rnk Aug 25, 2025
09f7c3f
Merge remote-tracking branch 'rnk-github/llvm-dylib-default' into llv…
rnk Aug 25, 2025
bab774e
Remove bolt modifications
rnk Aug 25, 2025
99ec42f
Opt AIX out of the change and update release notes to match
rnk Aug 25, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
5 changes: 5 additions & 0 deletions clang/docs/ReleaseNotes.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -179,6 +179,11 @@ Non-comprehensive list of changes in this release
Currently, the use of ``__builtin_dedup_pack`` is limited to template arguments and base
specifiers, it also must be used within a template context.

- On non-Windows platforms, Clang now builds as a large shared library,
``libclang-cpp``, by default. To revert to the old behavior of producing and
linking static libraries, pass ``-DCLANG_LINK_CLANG_DYLIB=OFF`` to CMake when
configuring your build. The new behavior matches LLVM, which also builds as a
large shared library.

New Compiler Flags
------------------
Expand Down
12 changes: 10 additions & 2 deletions llvm/CMakeLists.txt
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -932,14 +932,22 @@ if(NOT MSVC OR LLVM_BUILD_LLVM_DYLIB_VIS)
set(CAN_BUILD_LLVM_DYLIB ON)
endif()

cmake_dependent_option(LLVM_LINK_LLVM_DYLIB "Link tools against the libllvm dynamic library" OFF
# Link the tools against the libllvm DSO by default.
set(LLVM_LINK_LLVM_DYLIB_default ON)
Copy link
Collaborator

@hubert-reinterpretcast hubert-reinterpretcast Jun 26, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

As mentioned on the RFC thread, the deployment story on AIX does not work well with such a configuration (due to lack of relative rpath support).

Copy link
Collaborator Author

@rnk rnk Aug 25, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I opted AIX out of the change and updated the release notes. I expect this will not be the last platform opt-out.

if (BUILD_SHARED_LIBS OR WIN32)
set(LLVM_LINK_LLVM_DYLIB_default OFF)
endif()

cmake_dependent_option(LLVM_LINK_LLVM_DYLIB "Link tools against the libllvm dynamic library"
"${LLVM_LINK_LLVM_DYLIB_default}"
"CAN_BUILD_LLVM_DYLIB" OFF)

set(LLVM_BUILD_LLVM_DYLIB_default OFF)
if(LLVM_LINK_LLVM_DYLIB OR LLVM_BUILD_LLVM_C_DYLIB)
set(LLVM_BUILD_LLVM_DYLIB_default ON)
endif()
cmake_dependent_option(LLVM_BUILD_LLVM_DYLIB "Build libllvm dynamic library" ${LLVM_BUILD_LLVM_DYLIB_default}
cmake_dependent_option(LLVM_BUILD_LLVM_DYLIB "Build libllvm dynamic library"
"${LLVM_BUILD_LLVM_DYLIB_default}"
"CAN_BUILD_LLVM_DYLIB" OFF)

cmake_dependent_option(LLVM_DYLIB_EXPORT_INLINES "Force inline members of classes to be DLL exported when
Expand Down
5 changes: 5 additions & 0 deletions llvm/docs/ReleaseNotes.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -69,6 +69,11 @@ Changes to LLVM infrastructure
Changes to building LLVM
------------------------

* On non-Windows platforms, LLVM now builds as a large shared library, `libLLVM`,
by default. To revert to the old behavior of producing and linking static
libraries, pass ``-DLLVM_LINK_LLVM_DYLIB=OFF`` to CMake when configuring your
build.

Changes to TableGen
-------------------

Expand Down
Loading