Merge branch 'main' into mlem

Author: AZero13

clang/docs/ReleaseNotes.rst

@@ -191,6 +191,8 @@ C23 Feature Support
 - Added ``FLT_SNAN``, ``DBL_SNAN``, and ``LDBL_SNAN`` to Clang's ``<float.h>``
   header in C23 and later modes. This implements
   `WG14 N2710 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2710.htm>`_.
+- Fixed accepting as compatible unnamed tag types with the same fields within
+  the same translation unit but from different types.
 
 Non-comprehensive list of changes in this release
 -------------------------------------------------

clang/lib/AST/ASTContext.cpp

@@ -11581,6 +11581,12 @@ QualType ASTContext::mergeTagDefinitions(QualType LHS, QualType RHS) {
   if (LangOpts.CPlusPlus || !LangOpts.C23)
     return {};
 
+  // Nameless tags are comparable only within outer definitions. At the top
+  // level they are not comparable.
+  const TagDecl *LTagD = LHS->castAsTagDecl(), *RTagD = RHS->castAsTagDecl();
+  if (!LTagD->getIdentifier() || !RTagD->getIdentifier())
+    return {};
+
   // C23, on the other hand, requires the members to be "the same enough", so
   // we use a structural equivalence check.
   StructuralEquivalenceContext::NonEquivalentDeclSet NonEquivalentDecls;

clang/lib/AST/ASTStructuralEquivalence.cpp

@@ -1763,19 +1763,6 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
   // another anonymous structure or union, respectively, if their members
   // fulfill the preceding requirements. ... Otherwise, the structure, union,
   // or enumerated types are incompatible.
-
-  // Note: "the same tag" refers to the identifier for the structure; two
-  // structures without names are not compatible within a TU. In C23, if either
-  // declaration has no name, they're not equivalent. However, the paragraph
-  // after the bulleted list goes on to talk about compatibility of anonymous
-  // structure and union members, so this prohibition only applies to top-level
-  // declarations; if either declaration is not a member, they cannot be
-  // compatible.
-  if (Context.LangOpts.C23 && (!D1->getIdentifier() || !D2->getIdentifier()) &&
-      (!D1->getDeclContext()->isRecord() || !D2->getDeclContext()->isRecord()))
-    return false;
-
-  // Otherwise, check the names for equivalence.
   if (!NameIsStructurallyEquivalent(*D1, *D2))
     return false;
 

clang/lib/CIR/CodeGen/CIRGenStmt.cpp

@@ -536,7 +536,7 @@ mlir::LogicalResult CIRGenFunction::emitLabel(const clang::LabelDecl &d) {
   mlir::Block *currBlock = builder.getBlock();
   mlir::Block *labelBlock = currBlock;
 
-  if (!currBlock->empty()) {
+  if (!currBlock->empty() || currBlock->isEntryBlock()) {
     {
       mlir::OpBuilder::InsertionGuard guard(builder);
       labelBlock = builder.createBlock(builder.getBlock()->getParent());

clang/lib/StaticAnalyzer/Checkers/WebKit/ASTUtils.cpp

@@ -26,6 +26,7 @@ bool tryToFindPtrOrigin(
     const Expr *E, bool StopAtFirstRefCountedObj,
     std::function<bool(const clang::CXXRecordDecl *)> isSafePtr,
     std::function<bool(const clang::QualType)> isSafePtrType,
+    std::function<bool(const clang::Decl *)> isSafeGlobalDecl,
     std::function<bool(const clang::Expr *, bool)> callback) {
   while (E) {
     if (auto *DRE = dyn_cast<DeclRefExpr>(E)) {
@@ -34,6 +35,8 @@ bool tryToFindPtrOrigin(
         auto IsImmortal = safeGetName(VD) == "NSApp";
         if (VD->hasGlobalStorage() && (IsImmortal || QT.isConstQualified()))
           return callback(E, true);
+        if (VD->hasGlobalStorage() && isSafeGlobalDecl(VD))
+          return callback(E, true);
       }
     }
     if (auto *tempExpr = dyn_cast<MaterializeTemporaryExpr>(E)) {
@@ -71,9 +74,11 @@ bool tryToFindPtrOrigin(
     }
     if (auto *Expr = dyn_cast<ConditionalOperator>(E)) {
       return tryToFindPtrOrigin(Expr->getTrueExpr(), StopAtFirstRefCountedObj,
-                                isSafePtr, isSafePtrType, callback) &&
+                                isSafePtr, isSafePtrType, isSafeGlobalDecl,
+                                callback) &&
              tryToFindPtrOrigin(Expr->getFalseExpr(), StopAtFirstRefCountedObj,
-                                isSafePtr, isSafePtrType, callback);
+                                isSafePtr, isSafePtrType, isSafeGlobalDecl,
+                                callback);
     }
     if (auto *cast = dyn_cast<CastExpr>(E)) {
       if (StopAtFirstRefCountedObj) {

clang/lib/StaticAnalyzer/Checkers/WebKit/ASTUtils.h

@@ -56,6 +56,7 @@ bool tryToFindPtrOrigin(
     const clang::Expr *E, bool StopAtFirstRefCountedObj,
     std::function<bool(const clang::CXXRecordDecl *)> isSafePtr,
     std::function<bool(const clang::QualType)> isSafePtrType,
+    std::function<bool(const clang::Decl *)> isSafeGlobalDecl,
     std::function<bool(const clang::Expr *, bool)> callback);
 
 /// For \p E referring to a ref-countable/-counted pointer/reference we return

clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefCallArgsChecker.cpp

@@ -29,12 +29,12 @@ namespace {
 class RawPtrRefCallArgsChecker
     : public Checker<check::ASTDecl<TranslationUnitDecl>> {
   BugType Bug;
-  mutable BugReporter *BR;
 
   TrivialFunctionAnalysis TFA;
   EnsureFunctionAnalysis EFA;
 
 protected:
+  mutable BugReporter *BR;
   mutable std::optional<RetainTypeChecker> RTC;
 
 public:
@@ -46,6 +46,7 @@ class RawPtrRefCallArgsChecker
   virtual bool isSafePtr(const CXXRecordDecl *Record) const = 0;
   virtual bool isSafePtrType(const QualType type) const = 0;
   virtual bool isSafeExpr(const Expr *) const { return false; }
+  virtual bool isSafeDecl(const Decl *) const { return false; }
   virtual const char *ptrKind() const = 0;
 
   void checkASTDecl(const TranslationUnitDecl *TUD, AnalysisManager &MGR,
@@ -214,6 +215,7 @@ class RawPtrRefCallArgsChecker
         Arg, /*StopAtFirstRefCountedObj=*/true,
         [&](const clang::CXXRecordDecl *Record) { return isSafePtr(Record); },
         [&](const clang::QualType T) { return isSafePtrType(T); },
+        [&](const clang::Decl *D) { return isSafeDecl(D); },
         [&](const clang::Expr *ArgOrigin, bool IsSafe) {
           if (IsSafe)
             return true;
@@ -479,6 +481,11 @@ class UnretainedCallArgsChecker final : public RawPtrRefCallArgsChecker {
            isa<ObjCMessageExpr>(E);
   }
 
+  bool isSafeDecl(const Decl *D) const final {
+    // Treat NS/CF globals in system header as immortal.
+    return BR->getSourceManager().isInSystemHeader(D->getLocation());
+  }
+
   const char *ptrKind() const final { return "unretained"; }
 };
 

clang/lib/StaticAnalyzer/Checkers/WebKit/RawPtrRefLocalVarsChecker.cpp

@@ -166,10 +166,10 @@ bool isGuardedScopeEmbeddedInGuardianScope(const VarDecl *Guarded,
 class RawPtrRefLocalVarsChecker
     : public Checker<check::ASTDecl<TranslationUnitDecl>> {
   BugType Bug;
-  mutable BugReporter *BR;
   EnsureFunctionAnalysis EFA;
 
 protected:
+  mutable BugReporter *BR;
   mutable std::optional<RetainTypeChecker> RTC;
 
 public:
@@ -180,6 +180,7 @@ class RawPtrRefLocalVarsChecker
   virtual bool isSafePtr(const CXXRecordDecl *) const = 0;
   virtual bool isSafePtrType(const QualType) const = 0;
   virtual bool isSafeExpr(const Expr *) const { return false; }
+  virtual bool isSafeDecl(const Decl *) const { return false; }
   virtual const char *ptrKind() const = 0;
 
   void checkASTDecl(const TranslationUnitDecl *TUD, AnalysisManager &MGR,
@@ -288,6 +289,7 @@ class RawPtrRefLocalVarsChecker
                 return isSafePtr(Record);
               },
               [&](const clang::QualType Type) { return isSafePtrType(Type); },
+              [&](const clang::Decl *D) { return isSafeDecl(D); },
               [&](const clang::Expr *InitArgOrigin, bool IsSafe) {
                 if (!InitArgOrigin || IsSafe)
                   return true;
@@ -443,6 +445,10 @@ class UnretainedLocalVarsChecker final : public RawPtrRefLocalVarsChecker {
     return ento::cocoa::isCocoaObjectRef(E->getType()) &&
            isa<ObjCMessageExpr>(E);
   }
+  bool isSafeDecl(const Decl *D) const final {
+    // Treat NS/CF globals in system header as immortal.
+    return BR->getSourceManager().isInSystemHeader(D->getLocation());
+  }
   const char *ptrKind() const final { return "unretained"; }
 };
 

clang/test/Analysis/Checkers/WebKit/mock-system-header.h

@@ -34,11 +34,17 @@ void os_log_msg(os_log_t oslog, os_log_type_t type, const char *msg, ...);
 
 typedef const struct __attribute__((objc_bridge(NSString))) __CFString * CFStringRef;
 
+extern CFStringRef const kCFURLTagNamesKey;
+
 #ifdef __OBJC__
 @class NSString;
 @interface SystemObject {
   NSString *ns_string;
   CFStringRef cf_string;
 }
 @end
+
+typedef NSString *NSNotificationName;
+extern "C" NSNotificationName NSApplicationDidBecomeActiveNotification;
+
 #endif

clang/test/Analysis/Checkers/WebKit/unretained-local-vars.mm

@@ -1,8 +1,11 @@
 // RUN: %clang_analyze_cc1 -analyzer-checker=alpha.webkit.UnretainedLocalVarsChecker -verify %s
 
 #import "objc-mock-types.h"
+#import "mock-system-header.h"
 
 void someFunction();
+extern "C" CFStringRef LocalGlobalCFString;
+extern "C" NSString *LocalGlobalNSString;
 
 namespace raw_ptr {
 void foo() {
@@ -547,6 +550,29 @@ void foo() {
 
 } // autoreleased
 
+namespace ns_global {
+
+void consumeCFString(CFStringRef);
+void consumeNSString(NSString *);
+
+void cf() {
+  auto *str = kCFURLTagNamesKey;
+  consumeCFString(str);
+  auto *localStr = LocalGlobalCFString;
+  // expected-warning@-1{{Local variable 'localStr' is unretained and unsafe [alpha.webkit.UnretainedLocalVarsChecker]}}
+  consumeCFString(localStr);
+}
+
+void ns() {
+  auto *str = NSApplicationDidBecomeActiveNotification;
+  consumeNSString(str);
+  auto *localStr = LocalGlobalNSString;
+  // expected-warning@-1{{Local variable 'localStr' is unretained and unsafe [alpha.webkit.UnretainedLocalVarsChecker]}}
+  consumeNSString(localStr);
+}
+
+}
+
 bool doMoreWorkOpaque(OtherObj*);
 SomeObj* provide();