[clang] Suppress a dangling false positive when owner is moved in member initializer. #114213
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member initializer.
This patch extends the filtering heuristic to apply for the
Lifetimebound code path.
This will suppress a common false positive:
```
namespace std {
template<typename T>
struct unique_ptr {
T &operator*();
T *get() const [[clang::lifetimebound]];
};
} // namespace std
struct X {
X(std::unique_ptr<int> up) :
pointer(up.get()), owner(std::move(up)) {}
int *pointer;
std::unique_ptr<int> owner;
};
```
llvmbot
added
clang
|
@llvm/pr-subscribers-clang Author: Haojian Wu (hokein) ChangesThis patch extends the filtering heuristic to apply for the Lifetimebound code path. This will suppress a common false positive: See #112751. Full diff: https://github.com/llvm/llvm-project/pull/114213.diff 2 Files Affected:
diff --git a/clang/lib/Sema/CheckExprLifetime.cpp b/clang/lib/Sema/CheckExprLifetime.cpp
index aa0a2e223e708f..33d308fe7bdb60 100644
--- a/clang/lib/Sema/CheckExprLifetime.cpp
+++ b/clang/lib/Sema/CheckExprLifetime.cpp
@@ -1261,12 +1261,12 @@ static void checkExprLifetimeImpl(Sema &SemaRef,
if (pathContainsInit(Path))
return false;
+ auto *DRE = dyn_cast<DeclRefExpr>(L);
// Suppress false positives for code like the one below:
- // Ctor(unique_ptr<T> up) : member(*up), member2(move(up)) {}
- if (IsLocalGslOwner && pathOnlyHandlesGslPointer(Path))
+ // Ctor(unique_ptr<T> up) : pointer(up.get()), owner(move(up)) {}
+ if (DRE && isRecordWithAttr<OwnerAttr>(DRE->getType()))
return false;
- auto *DRE = dyn_cast<DeclRefExpr>(L);
auto *VD = DRE ? dyn_cast<VarDecl>(DRE->getDecl()) : nullptr;
if (!VD) {
// A member was initialized to a local block.
diff --git a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
index 688f55edfe84df..6a2af01ea5116c 100644
--- a/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
+++ b/clang/test/Sema/warn-lifetime-analysis-nocfg.cpp
@@ -384,6 +384,19 @@ struct X {
std::unique_ptr<int> pointer;
};
+struct [[gsl::Owner]] XOwner {
+ int* get() const [[clang::lifetimebound]];
+};
+struct X2 {
+ // A common usage that moves the passing owner to the class.
+ // verify no warning on this case.
+ X2(XOwner owner) :
+ pointee(owner.get()),
+ owner(std::move(owner)) {}
+ int* pointee;
+ XOwner owner;
+};
+
std::vector<int>::iterator getIt();
std::vector<int> getVec();
|
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/73/builds/7886 Here is the relevant piece of the build log for the reference |
smallp-o-p
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to smallp-o-p/llvm-project
that referenced
this pull request
Nov 3, 2024
…ber initializer. (llvm#114213) This patch extends the filtering heuristic to apply for the Lifetimebound code path. This will suppress a common false positive: ``` namespace std { template<typename T> struct unique_ptr { T &operator*(); T *get() const [[clang::lifetimebound]]; }; } // namespace std struct X { X(std::unique_ptr<int> up) : pointer(up.get()), owner(std::move(up)) {} int *pointer; std::unique_ptr<int> owner; }; ``` See llvm#114201.
NoumanAmir657
pushed a commit
to NoumanAmir657/llvm-project
that referenced
this pull request
Nov 4, 2024
…ber initializer. (llvm#114213) This patch extends the filtering heuristic to apply for the Lifetimebound code path. This will suppress a common false positive: ``` namespace std { template<typename T> struct unique_ptr { T &operator*(); T *get() const [[clang::lifetimebound]]; }; } // namespace std struct X { X(std::unique_ptr<int> up) : pointer(up.get()), owner(std::move(up)) {} int *pointer; std::unique_ptr<int> owner; }; ``` See llvm#114201.
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This patch extends the filtering heuristic to apply for the Lifetimebound code path.
This will suppress a common false positive:
See #114201.