[clang] c8ec807 - [alpha.webkit.NoUnretainedMemberChecker] Add a new WebKit checker for unretained member variables and ivars. (#128641)
via cfe-commits
cfe-commits at lists.llvm.org
Sun Mar 9 23:30:11 PDT 2025
Author: Ryosuke Niwa
Date: 2025-03-09T23:30:08-07:00
New Revision: c8ec8073aa5d8e87a15d101ded149de399518bc1
URL: https://github.com/llvm/llvm-project/commit/c8ec8073aa5d8e87a15d101ded149de399518bc1
DIFF: https://github.com/llvm/llvm-project/commit/c8ec8073aa5d8e87a15d101ded149de399518bc1.diff
LOG: [alpha.webkit.NoUnretainedMemberChecker] Add a new WebKit checker for unretained member variables and ivars. (#128641)
Add a new WebKit checker for member variables and instance variables of
NS and CF types. A member variable or instance variable to a CF type
should be RetainPtr regardless of whether ARC is enabled or disabled,
and that of a NS type should be RetainPtr when ARC is disabled.
Added:
clang/test/Analysis/Checkers/WebKit/unretained-members-arc.mm
clang/test/Analysis/Checkers/WebKit/unretained-members.mm
Modified:
clang/docs/analyzer/checkers.rst
clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefMemberChecker.cpp
Removed:
################################################################################
diff --git a/clang/docs/analyzer/checkers.rst b/clang/docs/analyzer/checkers.rst
index e3dda3e4b32d6..c947f26204159 100644
--- a/clang/docs/analyzer/checkers.rst
+++ b/clang/docs/analyzer/checkers.rst
@@ -3522,6 +3522,19 @@ Raw pointers and references to an object which supports CheckedPtr or CheckedRef
See `WebKit Guidelines for Safer C++ Programming <https://github.com/WebKit/WebKit/wiki/Safer-CPP-Guidelines>`_ for details.
+alpha.webkit.NoUnretainedMemberChecker
+""""""""""""""""""""""""""""""""""""""""
+Raw pointers and references to a NS or CF object can't be used as class members or ivars. Only RetainPtr is allowed for CF types regardless of whether ARC is enabled or disabled. Only RetainPtr is allowed for NS types when ARC is disabled.
+
+.. code-block:: cpp
+
+ struct Foo {
+ NSObject *ptr; // warn
+ // ...
+ };
+
+See `WebKit Guidelines for Safer C++ Programming <https://github.com/WebKit/WebKit/wiki/Safer-CPP-Guidelines>`_ for details.
+
alpha.webkit.UnretainedLambdaCapturesChecker
""""""""""""""""""""""""""""""""""""""""""""
Raw pointers and references to NS or CF types can't be captured in lambdas. Only RetainPtr is allowed for CF types regardless of whether ARC is enabled or disabled, and only RetainPtr is allowed for NS types when ARC is disabled.
diff --git a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
index 5d2b70bdb3cc3..21b585169cf40 100644
--- a/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
+++ b/clang/include/clang/StaticAnalyzer/Checkers/Checkers.td
@@ -1765,6 +1765,10 @@ def NoUncheckedPtrMemberChecker : Checker<"NoUncheckedPtrMemberChecker">,
HelpText<"Check for no unchecked member variables.">,
Documentation<HasDocumentation>;
+def NoUnretainedMemberChecker : Checker<"NoUnretainedMemberChecker">,
+ HelpText<"Check for no unretained member variables.">,
+ Documentation<HasDocumentation>;
+
def UnretainedLambdaCapturesChecker : Checker<"UnretainedLambdaCapturesChecker">,
HelpText<"Check unretained lambda captures.">,
Documentation<HasDocumentation>;
diff --git a/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefMemberChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefMemberChecker.cpp
index 963f59831c8ed..593e6e3663639 100644
--- a/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefMemberChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefMemberChecker.cpp
@@ -31,12 +31,16 @@ class RawPtrRefMemberChecker
BugType Bug;
mutable BugReporter *BR;
+protected:
+ mutable std::optional<RetainTypeChecker> RTC;
+
public:
RawPtrRefMemberChecker(const char *description)
: Bug(this, description, "WebKit coding guidelines") {}
virtual std::optional<bool>
- isPtrCompatible(const clang::CXXRecordDecl *) const = 0;
+ isPtrCompatible(const clang::QualType,
+ const clang::CXXRecordDecl *R) const = 0;
virtual bool isPtrCls(const clang::CXXRecordDecl *) const = 0;
virtual const char *typeName() const = 0;
virtual const char *invariant() const = 0;
@@ -57,6 +61,12 @@ class RawPtrRefMemberChecker
ShouldVisitImplicitCode = false;
}
+ bool VisitTypedefDecl(const TypedefDecl *TD) override {
+ if (Checker->RTC)
+ Checker->RTC->visitTypedef(TD);
+ return true;
+ }
+
bool VisitRecordDecl(const RecordDecl *RD) override {
Checker->visitRecordDecl(RD);
return true;
@@ -69,6 +79,8 @@ class RawPtrRefMemberChecker
};
LocalVisitor visitor(this);
+ if (RTC)
+ RTC->visitTranslationUnitDecl(TUD);
visitor.TraverseDecl(TUD);
}
@@ -77,16 +89,22 @@ class RawPtrRefMemberChecker
return;
for (auto *Member : RD->fields()) {
- const Type *MemberType = Member->getType().getTypePtrOrNull();
+ auto QT = Member->getType();
+ const Type *MemberType = QT.getTypePtrOrNull();
if (!MemberType)
continue;
if (auto *MemberCXXRD = MemberType->getPointeeCXXRecordDecl()) {
- // If we don't see the definition we just don't know.
- if (MemberCXXRD->hasDefinition()) {
- std::optional<bool> isRCAble = isPtrCompatible(MemberCXXRD);
- if (isRCAble && *isRCAble)
- reportBug(Member, MemberType, MemberCXXRD, RD);
+ std::optional<bool> IsCompatible = isPtrCompatible(QT, MemberCXXRD);
+ if (IsCompatible && *IsCompatible)
+ reportBug(Member, MemberType, MemberCXXRD, RD);
+ } else {
+ std::optional<bool> IsCompatible = isPtrCompatible(QT, nullptr);
+ auto *PointeeType = MemberType->getPointeeType().getTypePtrOrNull();
+ if (IsCompatible && *IsCompatible) {
+ auto *Desugared = PointeeType->getUnqualifiedDesugaredType();
+ if (auto *ObjCType = dyn_cast_or_null<ObjCInterfaceType>(Desugared))
+ reportBug(Member, MemberType, ObjCType->getDecl(), RD);
}
}
}
@@ -107,11 +125,12 @@ class RawPtrRefMemberChecker
void visitIvarDecl(const ObjCContainerDecl *CD,
const ObjCIvarDecl *Ivar) const {
- const Type *IvarType = Ivar->getType().getTypePtrOrNull();
+ auto QT = Ivar->getType();
+ const Type *IvarType = QT.getTypePtrOrNull();
if (!IvarType)
return;
if (auto *IvarCXXRD = IvarType->getPointeeCXXRecordDecl()) {
- std::optional<bool> IsCompatible = isPtrCompatible(IvarCXXRD);
+ std::optional<bool> IsCompatible = isPtrCompatible(QT, IvarCXXRD);
if (IsCompatible && *IsCompatible)
reportBug(Ivar, IvarType, IvarCXXRD, CD);
}
@@ -151,13 +170,13 @@ class RawPtrRefMemberChecker
return false;
}
- template <typename DeclType, typename ParentDeclType>
+ template <typename DeclType, typename PointeeType, typename ParentDeclType>
void reportBug(const DeclType *Member, const Type *MemberType,
- const CXXRecordDecl *MemberCXXRD,
+ const PointeeType *Pointee,
const ParentDeclType *ClassCXXRD) const {
assert(Member);
assert(MemberType);
- assert(MemberCXXRD);
+ assert(Pointee);
SmallString<100> Buf;
llvm::raw_svector_ostream Os(Buf);
@@ -169,10 +188,13 @@ class RawPtrRefMemberChecker
printQuotedName(Os, Member);
Os << " in ";
printQuotedQualifiedName(Os, ClassCXXRD);
- Os << " is a "
- << (isa<PointerType>(MemberType) ? "raw pointer" : "reference") << " to "
- << typeName() << " ";
- printQuotedQualifiedName(Os, MemberCXXRD);
+ Os << " is a ";
+ if (printPointer(Os, MemberType) == PrintDeclKind::Pointer) {
+ auto Typedef = MemberType->getAs<TypedefType>();
+ assert(Typedef);
+ printQuotedQualifiedName(Os, Typedef->getDecl());
+ } else
+ printQuotedQualifiedName(Os, Pointee);
Os << "; " << invariant() << ".";
PathDiagnosticLocation BSLoc(Member->getSourceRange().getBegin(),
@@ -181,6 +203,15 @@ class RawPtrRefMemberChecker
Report->addRange(Member->getSourceRange());
BR->emitReport(std::move(Report));
}
+
+ enum class PrintDeclKind { Pointee, Pointer };
+ virtual PrintDeclKind printPointer(llvm::raw_svector_ostream &Os,
+ const Type *T) const {
+ T = T->getUnqualifiedDesugaredType();
+ bool IsPtr = isa<PointerType>(T) || isa<ObjCObjectPointerType>(T);
+ Os << (IsPtr ? "raw pointer" : "reference") << " to " << typeName() << " ";
+ return PrintDeclKind::Pointee;
+ }
};
class NoUncountedMemberChecker final : public RawPtrRefMemberChecker {
@@ -190,8 +221,9 @@ class NoUncountedMemberChecker final : public RawPtrRefMemberChecker {
"reference-countable type") {}
std::optional<bool>
- isPtrCompatible(const clang::CXXRecordDecl *R) const final {
- return isRefCountable(R);
+ isPtrCompatible(const clang::QualType,
+ const clang::CXXRecordDecl *R) const final {
+ return R && isRefCountable(R);
}
bool isPtrCls(const clang::CXXRecordDecl *R) const final {
@@ -212,8 +244,9 @@ class NoUncheckedPtrMemberChecker final : public RawPtrRefMemberChecker {
"checked-pointer capable type") {}
std::optional<bool>
- isPtrCompatible(const clang::CXXRecordDecl *R) const final {
- return isCheckedPtrCapable(R);
+ isPtrCompatible(const clang::QualType,
+ const clang::CXXRecordDecl *R) const final {
+ return R && isCheckedPtrCapable(R);
}
bool isPtrCls(const clang::CXXRecordDecl *R) const final {
@@ -228,6 +261,40 @@ class NoUncheckedPtrMemberChecker final : public RawPtrRefMemberChecker {
}
};
+class NoUnretainedMemberChecker final : public RawPtrRefMemberChecker {
+public:
+ NoUnretainedMemberChecker()
+ : RawPtrRefMemberChecker("Member variable is a raw-pointer/reference to "
+ "retainable type") {
+ RTC = RetainTypeChecker();
+ }
+
+ std::optional<bool>
+ isPtrCompatible(const clang::QualType QT,
+ const clang::CXXRecordDecl *) const final {
+ return RTC->isUnretained(QT);
+ }
+
+ bool isPtrCls(const clang::CXXRecordDecl *R) const final {
+ return isRetainPtr(R);
+ }
+
+ const char *typeName() const final { return "retainable type"; }
+
+ const char *invariant() const final {
+ return "member variables must be a RetainPtr";
+ }
+
+ PrintDeclKind printPointer(llvm::raw_svector_ostream &Os,
+ const Type *T) const final {
+ if (!isa<ObjCObjectPointerType>(T) && T->getAs<TypedefType>()) {
+ Os << typeName() << " ";
+ return PrintDeclKind::Pointer;
+ }
+ return RawPtrRefMemberChecker::printPointer(Os, T);
+ }
+};
+
} // namespace
void ento::registerNoUncountedMemberChecker(CheckerManager &Mgr) {
@@ -246,3 +313,11 @@ bool ento::shouldRegisterNoUncheckedPtrMemberChecker(
const CheckerManager &Mgr) {
return true;
}
+
+void ento::registerNoUnretainedMemberChecker(CheckerManager &Mgr) {
+ Mgr.registerChecker<NoUnretainedMemberChecker>();
+}
+
+bool ento::shouldRegisterNoUnretainedMemberChecker(const CheckerManager &Mgr) {
+ return true;
+}
diff --git a/clang/test/Analysis/Checkers/WebKit/unretained-members-arc.mm b/clang/test/Analysis/Checkers/WebKit/unretained-members-arc.mm
new file mode 100644
index 0000000000000..9820c875b87c0
--- /dev/null
+++ b/clang/test/Analysis/Checkers/WebKit/unretained-members-arc.mm
@@ -0,0 +1,39 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.NoUnretainedMemberChecker -fobjc-arc -verify %s
+
+#include "objc-mock-types.h"
+
+namespace members {
+
+ struct Foo {
+ private:
+ SomeObj* a = nullptr;
+
+ [[clang::suppress]]
+ SomeObj* a_suppressed = nullptr;
+
+ protected:
+ RetainPtr<SomeObj> b;
+
+ public:
+ SomeObj* c = nullptr;
+ RetainPtr<SomeObj> d;
+
+ CFMutableArrayRef e = nullptr;
+// expected-warning at -1{{Member variable 'e' in 'members::Foo' is a retainable type 'CFMutableArrayRef'}}
+ };
+
+ template<class T, class S>
+ struct FooTmpl {
+ T* x;
+ S y;
+// expected-warning at -1{{Member variable 'y' in 'members::FooTmpl<SomeObj, __CFArray *>' is a raw pointer to retainable type}}
+ };
+
+ void forceTmplToInstantiate(FooTmpl<SomeObj, CFMutableArrayRef>) {}
+
+ struct [[clang::suppress]] FooSuppressed {
+ private:
+ SomeObj* a = nullptr;
+ };
+
+}
diff --git a/clang/test/Analysis/Checkers/WebKit/unretained-members.mm b/clang/test/Analysis/Checkers/WebKit/unretained-members.mm
new file mode 100644
index 0000000000000..e068a583c18c5
--- /dev/null
+++ b/clang/test/Analysis/Checkers/WebKit/unretained-members.mm
@@ -0,0 +1,60 @@
+// RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.NoUnretainedMemberChecker -verify %s
+
+#include "objc-mock-types.h"
+
+namespace members {
+
+ struct Foo {
+ private:
+ SomeObj* a = nullptr;
+// expected-warning at -1{{Member variable 'a' in 'members::Foo' is a raw pointer to retainable type}}
+
+ [[clang::suppress]]
+ SomeObj* a_suppressed = nullptr;
+// No warning.
+
+ protected:
+ RetainPtr<SomeObj> b;
+// No warning.
+
+ public:
+ SomeObj* c = nullptr;
+// expected-warning at -1{{Member variable 'c' in 'members::Foo' is a raw pointer to retainable type}}
+ RetainPtr<SomeObj> d;
+
+ CFMutableArrayRef e = nullptr;
+// expected-warning at -1{{Member variable 'e' in 'members::Foo' is a retainable type 'CFMutableArrayRef'}}
+ };
+
+ template<class T, class S>
+ struct FooTmpl {
+ T* a;
+// expected-warning at -1{{Member variable 'a' in 'members::FooTmpl<SomeObj, __CFArray *>' is a raw pointer to retainable type}}
+ S b;
+// expected-warning at -1{{Member variable 'b' in 'members::FooTmpl<SomeObj, __CFArray *>' is a raw pointer to retainable type}}
+ };
+
+ void forceTmplToInstantiate(FooTmpl<SomeObj, CFMutableArrayRef>) {}
+
+ struct [[clang::suppress]] FooSuppressed {
+ private:
+ SomeObj* a = nullptr;
+// No warning.
+ };
+
+}
+
+namespace ignore_unions {
+ union Foo {
+ SomeObj* a;
+ RetainPtr<SomeObj> b;
+ CFMutableArrayRef c;
+ };
+
+ template<class T>
+ union RefPtr {
+ T* a;
+ };
+
+ void forceTmplToInstantiate(RefPtr<SomeObj>) {}
+}
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