[clang] [webkit.UncountedLambdaCapturesChecker] Ignore lambda invocation with arguments (PR #117394)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang-static-analyzer-1

Author: Ryosuke Niwa (rniwa)

<details>
<summary>Changes</summary>

Fixed a bug that UncountedLambdaCapturesChecker would emit a warning on a lambda capture when the lambda is invoked with arguments. LocalVisitor::VisitCallExpr was not tolerating a lambda invocation with more than 1 arguments.

---
Full diff: https://github.com/llvm/llvm-project/pull/117394.diff


2 Files Affected:

- (modified) clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLambdaCapturesChecker.cpp (+1-1) 
- (modified) clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp (+8-1) 


``````````diff
diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLambdaCapturesChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLambdaCapturesChecker.cpp
index 9312bf0af16dbf..599c2179db0f0e 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLambdaCapturesChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/UncountedLambdaCapturesChecker.cpp
@@ -114,7 +114,7 @@ class UncountedLambdaCapturesChecker
         if (!DRE)
           return;
         auto *MD = dyn_cast_or_null<CXXMethodDecl>(DRE->getDecl());
-        if (!MD || CE->getNumArgs() != 1)
+        if (!MD || CE->getNumArgs() < 1)
           return;
         auto *Arg = CE->getArg(0)->IgnoreParenCasts();
         auto *ArgRef = dyn_cast<DeclRefExpr>(Arg);
diff --git a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
index b63ffed8809fef..65eee9d49106df 100644
--- a/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
+++ b/clang/test/Analysis/Checkers/WebKit/uncounted-lambda-captures.cpp
@@ -125,7 +125,7 @@ void noescape_lambda() {
 }
 
 void lambda_capture_param(RefCountable* obj) {
-  auto someLambda = [&] {
+  auto someLambda = [&]() {
     obj->method();
   };
   someLambda();
@@ -178,3 +178,10 @@ void trivial_lambda() {
   };
   trivial_lambda();
 }
+
+void lambda_with_args(RefCountable* obj) {
+  auto trivial_lambda = [&](int v) {
+    obj->method();
+  };
+  trivial_lambda(1);
+}

``````````

</details>


https://github.com/llvm/llvm-project/pull/117394