[clang] [webkit.UncountedLambdaCapturesChecker] Treat a call to lambda function via a variable as safe. (PR #135688)

[Ryosuke Niwa via cfe-commits]

https://github.com/rniwa created https://github.com/llvm/llvm-project/pull/135688

This PR makes the checker ignore a function call to lambda via a local variable.

>From 41992e5ffb43f7db7704b93c7ad5fe2135e86e26 Mon Sep 17 00:00:00 2001
From: Ryosuke Niwa <rniwa at webkit.org>
Date: Mon, 14 Apr 2025 15:12:10 -0700
Subject: [PATCH] [webkit.UncountedLambdaCapturesChecker] Treat a call to
 lambda function via a variable as safe.

This PR makes the checker ignore a function call to lambda via a local variable.
---
 .../Checkers/WebKit/RawPtrRefLambdaCapturesChecker.cpp    | 2 --
 .../Checkers/WebKit/uncounted-lambda-captures.cpp         | 8 ++++++++
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefLambdaCapturesChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefLambdaCapturesChecker.cpp
index da403d591a2e2..0a658b59ad8c5 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefLambdaCapturesChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefLambdaCapturesChecker.cpp
@@ -263,8 +263,6 @@ class RawPtrRefLambdaCapturesChecker
           return;
         DeclRefExprsToIgnore.insert(ArgRef);
         LambdasToIgnore.insert(L);
-        Checker->visitLambdaExpr(L, shouldCheckThis() && !hasProtectedThis(L),
-                                 ClsType, /* ignoreParamVarDecl */ true);
       }
 
       bool hasProtectedThis(LambdaExpr *L) {
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
index 36135973e78c0..cc3d27bbc1375 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
@@ -372,6 +372,14 @@ void trivial_lambda() {
   trivial_lambda();
 }
 
+bool call_lambda_var_decl() {
+  RefCountable* ref_countable = make_obj();
+  auto lambda = [&]() -> bool {
+    return ref_countable->next();
+  };
+  return lambda();
+}
+
 void lambda_with_args(RefCountable* obj) {
   auto trivial_lambda = [&](int v) {
     obj->method();