[NFC][CLANG] Fix static analyzer bugs about unnecessary object copies with auto keyword

[smanna12]

Reported by Static Analyzer Tool:
In clang::dataflow::Environment::initialize(): Using the auto keyword without an & causes the copy of an object of type LambdaCapture

[llvmbot]

@llvm/pr-subscribers-clang-analysis

@llvm/pr-subscribers-clang

Author: None (smanna12)

Changes

Reported by Static Analyzer Tool:
In clang::dataflow::Environment::initialize(): Using the auto keyword without an & causes the copy of an object of type LambdaCapture

---

Full diff: https://github.com/llvm/llvm-project/pull/85962.diff

1 Files Affected:

• (modified) clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp (+1-1)

diff --git a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
index cc1ebd511191a9..70e0623805a8cf 100644
--- a/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
+++ b/clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp
@@ -416,7 +416,7 @@ void Environment::initialize() {
     assert(Parent != nullptr);
 
     if (Parent->isLambda()) {
-      for (auto Capture : Parent->captures()) {
+      for (const auto &Capture : Parent->captures()) {
         if (Capture.capturesVariable()) {
           const auto *VarDecl = Capture.getCapturedVar();
           assert(VarDecl != nullptr);

[ymand]

Looks good, but per LLVM style guidelines, should we go ahead and replace the auto as well?

[tahonermann]

This looks fine to me. LambdaCapture consists of a pointer and two source locations so is relatively small and thus, this doesn't address a performance concern. Having the variable be const is good regardless to avoid unintended mutation.

[smanna12]

Thank you for reviews!