[clangd] Add clangd 20 release notes

[HighCommander4]

No description provided.

[llvmbot]

@llvm/pr-subscribers-clang-tools-extra

Author: Nathan Ridge (HighCommander4)

Changes

---

Full diff: https://github.com/llvm/llvm-project/pull/127358.diff

1 Files Affected:

• (modified) clang-tools-extra/docs/ReleaseNotes.rst (+53-3)

diff --git a/clang-tools-extra/docs/ReleaseNotes.rst b/clang-tools-extra/docs/ReleaseNotes.rst
index cc5f64a3f9fa3..35de182ceddf4 100644
--- a/clang-tools-extra/docs/ReleaseNotes.rst
+++ b/clang-tools-extra/docs/ReleaseNotes.rst
@@ -56,7 +56,8 @@ Improvements to clangd
 Inlay hints
 ^^^^^^^^^^^
 
-- Added `DefaultArguments` Inlay Hints option.
+- Added support for inlay hints for default arguments, enabled using the
+  `DefaultArguments` config option (#GH95712)
 
 Diagnostics
 ^^^^^^^^^^^
@@ -67,21 +68,45 @@ Semantic Highlighting
 Compile flags
 ^^^^^^^^^^^^^
 
+- Fixed a bug where clangd would unnecessarily reparse open files whose
+  compile command did not change when receiving a new compile command
+  via an LSP `workspace/configuration` request (#GH115438)
+
 Hover
 ^^^^^
 
+- Hovering over a function name now shows the function's documentation
+  comment even if the comment is written above the function's out-of-line
+  definition in a different source file (#GH67802)
+
 Code completion
 ^^^^^^^^^^^^^^^
 
+- Added an `ArgumentLists` config option under `Completion`. This is a more
+  flexible version of the `--function-arg-placeholders` command line flag,
+  allowing users more detailed control of what is inserted in argument list
+  position when clangd completes the name of a function in a function call
+  context. (#GH111322)
+- Clangd now supports configuring which headers should be inserted using 
+  `<>` vs. `""` syntax using the `QuotedHeaders` and `AngledHeaders` config
+  options under `Style` (#GH67749)
 - Added completion for C++20 keywords.
+- Clangd's `HeuristicResolver` component was upstreamed to `libSema` where
+  code completion can take advantage of it, resulting in improved code
+  completion in templated code
+- Code completion proposals for symbols defined in included headers now
+  include documentation comments (#GH120099)
 
 Code actions
 ^^^^^^^^^^^^
 
 - Added `Swap operands` tweak for certain binary operators.
-
 - Improved the extract-to-function code action to allow extracting statements
   with overloaded operators like ``<<`` of ``std::ostream``.
+- `Define outline` now handles member functions of class templates, and
+  member function templates.
+- `Extract variable` can now operate on the top-level expression in an
+  expression statement (#GH112525)
 
 Signature help
 ^^^^^^^^^^^^^^
@@ -89,13 +114,38 @@ Signature help
 Cross-references
 ^^^^^^^^^^^^^^^^
 
+- Clangd now supports the "outgoing calls" direction of call hierarchy
+  (#GH77556)
+- Call hierarchy can now be invoked on fields and namespace-scope
+  variables (#GH113900)
+- Improved heuristics for filtering out generated Protobuf symbol names
+  during indexing (#GH110091)
+- Compiler intrinsics defined in `*intrin.h` system headers are now
+  indexed even if they have reserved names (#GH119735)
+- Various improvements to go-to-definition in templated code
+
 Objective-C
 ^^^^^^^^^^^
 
+Clang-tidy integration
+^^^^^^^^^^^^^^^^^^^^^^
+
+- Improved robustness in handling clang-tidy check names (#GH109421)
+
+C++20 Modules Support
+^^^^^^^^^^^^^^^^^^^^^
+
+- Support code completion for symbols defined in modules (#GH110083)
+- Improve performance when opening files that import modules (#GH106683)
+- Compile commands for modules now respect modifications specified in `.clangd`
+  files (#GH122606)
+
 Miscellaneous
 ^^^^^^^^^^^^^
 
-- The DefineOutline tweak now handles member functions of class templates.
+- Fixed an OOM affecting some versions of libcxx headers compiled in C++20
+  mode (#GH108866)
+- Various other stability improvements, e.g. crash fixes
 
 Improvements to clang-doc
 -------------------------

[HighCommander4]

@ChuanqiXu9 I would appreciate if you could look over this section in particular. I added entries for the modules-related commits that seemed notable to me, but I'm definitely happy to add other entries / add more details / adjust wording etc.

[HighCommander4]

@ChuanqiXu9 and a follow-up question, do you think we should make any update to https://clangd.llvm.org/features#experimental-c20-modules-support for clangd 20?

[ChuanqiXu9]

I think the current wording is fine. Or we can say we improved the efficiency of support for modules in clangd20.

[kadircet]

thanks a lot!

[HighCommander4]

Thanks all for the reviews!

Adding @tstellar to request merging this to the llvm 20 branch.

[HighCommander4]

(Just realized this might be getting overlooked because it's not in the LLVM 20.X Release milestone. Added it now.)

[github-actions]

@HighCommander4 (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix. When you are done, please add the release:note label to this PR.