Merge branch 'fix/163090' of https://github.com/a-tarasyuk/llvm-project into fix/163090

Author: a-tarasyuk

clang/docs/PointerAuthentication.rst

@@ -592,6 +592,36 @@ The result value is never zero and always within range for both the
 
 This can be used in constant expressions.
 
+``ptrauth_type_discriminator``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: c
+
+  ptrauth_type_discriminator(type)
+
+Compute the constant discriminator derived from the given type, as is computed
+for automatically type diversified schemas.
+
+``type`` must be a type. The result has the type ``ptrauth_extra_data_t``.
+
+This can be used in constant expressions.
+
+``ptrauth_function_pointer_type_discriminator``
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: c
+
+  ptrauth_function_pointer_type_discriminator(function_type)
+
+Compute the constant discriminator derived from the provided function type, for
+use in contexts where the default function authentication schema. If function
+pointer type diversity is enabled, this is equivalent to
+`ptrauth_type_discriminator(function_type)`, if it is not enabled this is `0`.
+
+``function_type`` must be a function type. The result has the type ``ptrauth_extra_data_t``.
+
+This can be used in constant expressions.
+
 ``ptrauth_strip``
 ^^^^^^^^^^^^^^^^^
 

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/Headers/ptrauth.h

@@ -241,6 +241,18 @@ typedef __UINTPTR_TYPE__ ptrauth_generic_signature_t;
 #define ptrauth_type_discriminator(__type)                                     \
   __builtin_ptrauth_type_discriminator(__type)
 
+/* Compute the constant discriminator used by Clang to sign pointers with the
+   given C function pointer type.
+
+   A call to this function is an integer constant expression. */
+#if __has_feature(ptrauth_function_pointer_type_discrimination)
+#define ptrauth_function_pointer_type_discriminator(__type)                    \
+  __builtin_ptrauth_type_discriminator(__type)
+#else
+#define ptrauth_function_pointer_type_discriminator(__type)                    \
+  ((ptrauth_extra_data_t)0)
+#endif
+
 /* Compute a signature for the given pair of pointer-sized values.
    The order of the arguments is significant.
 
@@ -372,6 +384,8 @@ typedef __UINTPTR_TYPE__ ptrauth_generic_signature_t;
   })
 
 #define ptrauth_type_discriminator(__type) ((ptrauth_extra_data_t)0)
+#define ptrauth_function_pointer_type_discriminator(__type)                    \
+  ((ptrauth_extra_data_t)0)
 
 #define ptrauth_sign_generic_data(__value, __data)                             \
   ({                                                                           \

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"; }
 };