From 65f42d27525c8e4008e7f1e67f03204d430ce581 Mon Sep 17 00:00:00 2001
From: Xianpeng Shen <3353385+shenxianpeng@users.noreply.github.com>
Date: Mon, 9 Nov 2026 20:54:47 +0000
Subject: [PATCH] perf: leave `clang-analyzer-*` out of the default
 `--tidy-checks`

The Clang Static Analyzer checks can make clang-tidy many times slower
(see #518). clang-tidy 22 removed them from its own defaults, but our
default added them back. Users can still enable them in a .clang-tidy
file or with --tidy-checks.

Document the change in the CLI help and the migration guide, including
that clang-tidy 21 and older still enable them by default.

Part of #518
---
 cpp-linter/src/cli/mod.rs |  7 ++++++-
 docs/docs/migration.md    | 13 +++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/cpp-linter/src/cli/mod.rs b/cpp-linter/src/cli/mod.rs
index 5c57ac11..4e8c04e3 100644
--- a/cpp-linter/src/cli/mod.rs
+++ b/cpp-linter/src/cli/mod.rs
@@ -403,12 +403,17 @@ pub struct TidyOptions {
     ///   `'-*'`.
     /// - It is also possible to rely solely on a .clang-tidy config file by
     ///   specifying this option as a blank string (`''`).
+    /// - The default does not add the Clang Static Analyzer checks
+    ///   (`clang-analyzer-*`) because they can make clang-tidy many times slower.
+    ///   clang-tidy 22 and newer also leave them out of their own defaults.
+    ///   clang-tidy 21 and older still enable them unless `-clang-analyzer-*` is added.
+    ///   Add `clang-analyzer-*` to this option or to a .clang-tidy file to enable them.
     ///
     /// See also clang-tidy docs for more info.
     #[cfg_attr(feature = "bin", arg(
         short = 'c',
         long,
-        default_value = "boost-*,bugprone-*,performance-*,readability-*,portability-*,modernize-*,clang-analyzer-*,cppcoreguidelines-*",
+        default_value = "boost-*,bugprone-*,performance-*,readability-*,portability-*,modernize-*,cppcoreguidelines-*",
         default_missing_value = "",
         num_args = 0..=1,
         help_heading = "Clang-tidy options",
diff --git a/docs/docs/migration.md b/docs/docs/migration.md
index 6e2a7e30..30a2516f 100644
--- a/docs/docs/migration.md
+++ b/docs/docs/migration.md
@@ -6,6 +6,7 @@
 [mod-sys]: cli.md#-mod-sys
 [no-mod-sys]: cli.md#-no-mod-sys
 [ignore]: cli.md#-i-ignore
+[tidy-checks]: cli.md#-c-tidy-checks
 [database]: cli.md#-p-database
 [repo-root]: cli.md#-r-repo-root
 [pr-review]: cli.md#-p-pr-review
@@ -77,6 +78,7 @@ The old names can still be given together, as in v1 (for example
 |---|---|---|
 | [`-l`, `--lines-changed-only`][lines-changed-only] | `false` | `true` |
 | [`-i`, `--ignore`][ignore] | `.github` | `.github` and `target` |
+| [`-c`, `--tidy-checks`][tidy-checks] | includes `clang-analyzer-*` | no `clang-analyzer-*` |
 
 Because `--lines-changed-only` is `true` by default and implies
 [`--files-changed-only`][files-changed-only], v2 analyzes only the added lines of changed files
@@ -87,6 +89,17 @@ including files under `target`, pass:
 cpp-linter --lines-changed-only=false --files-changed-only=false --ignore=.github
 ```
 
+The default [`--tidy-checks`][tidy-checks] no longer adds the Clang Static Analyzer checks
+(`clang-analyzer-*`), because they can make clang-tidy many times slower. clang-tidy 22 and newer
+also leave them out of their own defaults, so with those versions they only run if a `.clang-tidy`
+file or `--tidy-checks` enables them. clang-tidy 21 and older still enable them by default; add
+`-clang-analyzer-*` to `--tidy-checks` to turn them off there. To keep them with any version, add
+them back:
+
+```shell
+cpp-linter --tidy-checks="boost-*,bugprone-*,performance-*,readability-*,portability-*,modernize-*,clang-analyzer-*,cppcoreguidelines-*"
+```
+
 ## Fixes are written to a patch
 
 In v1, `--fix` applied clang-format fixes in place, editing the files in the working tree.