Merge from 'main' to 'sycl-web' (20 commits)

  CONFLICT (content): Merge conflict in clang/test/Driver/openmp-offload-gpu.c

clang/docs/ReleaseNotes.rst

@@ -218,6 +218,10 @@ Bug Fixes in This Version
   for logical operators in C23.
   Fixes (`#64356 <https://github.com/llvm/llvm-project/issues/64356>`_).
 
+- Clang no longer produces a false-positive `-Wunused-variable` warning
+  for variables created through copy initialization having side-effects in C++17 and later.
+  Fixes (`#79518 <https://github.com/llvm/llvm-project/issues/79518>`_).
+
 Bug Fixes to Compiler Builtins
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
@@ -298,6 +302,15 @@ Bug Fixes to C++ Support
   Fixes (`#82941 <https://github.com/llvm/llvm-project/issues/82941>`_),
   (`#42411 <https://github.com/llvm/llvm-project/issues/42411>`_), and
   (`#18121 <https://github.com/llvm/llvm-project/issues/18121>`_).
+- Clang now properly reports supported C++11 attributes when using
+  ``__has_cpp_attribute`` and parses attributes with arguments in C++03
+  (`#82995 <https://github.com/llvm/llvm-project/issues/82995>`_)
+- Clang now properly diagnoses missing 'default' template arguments on a variety
+  of templates. Previously we were diagnosing on any non-function template
+  instead of only on class, alias, and variable templates, as last updated by
+  CWG2032.
+  Fixes (`#83461 <https://github.com/llvm/llvm-project/issues/83461>`_)
+
 
 Bug Fixes to AST Handling
 ^^^^^^^^^^^^^^^^^^^^^^^^^

clang/include/clang/Sema/Scope.h

@@ -534,6 +534,25 @@ class Scope {
     return false;
   }
 
+  /// Determine if this scope (or its parents) are a compute construct inside of
+  /// the nearest 'switch' scope.  This is needed to check whether we are inside
+  /// of a 'duffs' device, which is an illegal branch into a compute construct.
+  bool isInOpenACCComputeConstructBeforeSwitch() const {
+    for (const Scope *S = this; S; S = S->getParent()) {
+      if (S->getFlags() & Scope::OpenACCComputeConstructScope)
+        return true;
+      if (S->getFlags() & Scope::SwitchScope)
+        return false;
+
+      if (S->getFlags() &
+          (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
+           Scope::TemplateParamScope | Scope::FunctionPrototypeScope |
+           Scope::AtCatchScope | Scope::ObjCMethodScope))
+        return false;
+    }
+    return false;
+  }
+
   /// Determine whether this scope is a while/do/for statement, which can have
   /// continue statements embedded into it.
   bool isContinueScope() const {

clang/lib/AST/Interp/ByteCodeExprGen.cpp

@@ -2842,7 +2842,8 @@ bool ByteCodeExprGen<Emitter>::VisitCallExpr(const CallExpr *E) {
         return false;
     } else if (Func->isVariadic()) {
       uint32_t VarArgSize = 0;
-      unsigned NumParams = Func->getNumWrittenParams();
+      unsigned NumParams =
+          Func->getNumWrittenParams() + isa<CXXOperatorCallExpr>(E);
       for (unsigned I = NumParams, N = E->getNumArgs(); I != N; ++I)
         VarArgSize += align(primSize(classify(E->getArg(I)).value_or(PT_Ptr)));
       if (!this->emitCallVar(Func, VarArgSize, E))

clang/lib/AST/Interp/Context.cpp

@@ -41,8 +41,8 @@ bool Context::isPotentialConstantExpr(State &Parent, const FunctionDecl *FD) {
 }
 
 bool Context::evaluateAsRValue(State &Parent, const Expr *E, APValue &Result) {
-  assert(Stk.empty());
-  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk, Result);
+  bool Recursing = !Stk.empty();
+  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk);
 
   auto Res = C.interpretExpr(E, /*ConvertResultToRValue=*/E->isGLValue());
 
@@ -51,42 +51,47 @@ bool Context::evaluateAsRValue(State &Parent, const Expr *E, APValue &Result) {
     return false;
   }
 
-  assert(Stk.empty());
+  if (!Recursing) {
+    assert(Stk.empty());
 #ifndef NDEBUG
-  // Make sure we don't rely on some value being still alive in
-  // InterpStack memory.
-  Stk.clear();
+    // Make sure we don't rely on some value being still alive in
+    // InterpStack memory.
+    Stk.clear();
 #endif
+  }
 
   Result = Res.toAPValue();
 
   return true;
 }
 
 bool Context::evaluate(State &Parent, const Expr *E, APValue &Result) {
-  assert(Stk.empty());
-  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk, Result);
+  bool Recursing = !Stk.empty();
+  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk);
 
   auto Res = C.interpretExpr(E);
   if (Res.isInvalid()) {
     Stk.clear();
     return false;
   }
 
-  assert(Stk.empty());
+  if (!Recursing) {
+    assert(Stk.empty());
 #ifndef NDEBUG
-  // Make sure we don't rely on some value being still alive in
-  // InterpStack memory.
-  Stk.clear();
+    // Make sure we don't rely on some value being still alive in
+    // InterpStack memory.
+    Stk.clear();
 #endif
+  }
+
   Result = Res.toAPValue();
   return true;
 }
 
 bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD,
                                     APValue &Result) {
-  assert(Stk.empty());
-  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk, Result);
+  bool Recursing = !Stk.empty();
+  ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk);
 
   bool CheckGlobalInitialized =
       shouldBeGloballyIndexed(VD) &&
@@ -97,12 +102,14 @@ bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD,
     return false;
   }
 
-  assert(Stk.empty());
+  if (!Recursing) {
+    assert(Stk.empty());
 #ifndef NDEBUG
-  // Make sure we don't rely on some value being still alive in
-  // InterpStack memory.
-  Stk.clear();
+    // Make sure we don't rely on some value being still alive in
+    // InterpStack memory.
+    Stk.clear();
 #endif
+  }
 
   Result = Res.toAPValue();
   return true;
@@ -217,6 +224,9 @@ const CXXMethodDecl *
 Context::getOverridingFunction(const CXXRecordDecl *DynamicDecl,
                                const CXXRecordDecl *StaticDecl,
                                const CXXMethodDecl *InitialFunction) const {
+  assert(DynamicDecl);
+  assert(StaticDecl);
+  assert(InitialFunction);
 
   const CXXRecordDecl *CurRecord = DynamicDecl;
   const CXXMethodDecl *FoundFunction = InitialFunction;

clang/lib/AST/Interp/EvalEmitter.cpp

@@ -18,7 +18,7 @@ using namespace clang;
 using namespace clang::interp;
 
 EvalEmitter::EvalEmitter(Context &Ctx, Program &P, State &Parent,
-                         InterpStack &Stk, APValue &Result)
+                         InterpStack &Stk)
     : Ctx(Ctx), P(P), S(Parent, P, Stk, Ctx, this), EvalResult(&Ctx) {
   // Create a dummy frame for the interpreter which does not have locals.
   S.Current =

clang/lib/AST/Interp/EvalEmitter.h

@@ -41,8 +41,7 @@ class EvalEmitter : public SourceMapper {
   InterpState &getState() { return S; }
 
 protected:
-  EvalEmitter(Context &Ctx, Program &P, State &Parent, InterpStack &Stk,
-              APValue &Result);
+  EvalEmitter(Context &Ctx, Program &P, State &Parent, InterpStack &Stk);
 
   virtual ~EvalEmitter();
 

clang/lib/AST/Interp/Interp.h

@@ -199,6 +199,8 @@ bool InterpretBuiltin(InterpState &S, CodePtr OpPC, const Function *F,
 bool InterpretOffsetOf(InterpState &S, CodePtr OpPC, const OffsetOfExpr *E,
                        llvm::ArrayRef<int64_t> ArrayIndices, int64_t &Result);
 
+inline bool Invalid(InterpState &S, CodePtr OpPC);
+
 enum class ArithOp { Add, Sub };
 
 //===----------------------------------------------------------------------===//
@@ -522,6 +524,11 @@ bool IncDecHelper(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
   if (Ptr.isDummy())
     return false;
 
+  if constexpr (std::is_same_v<T, Boolean>) {
+    if (!S.getLangOpts().CPlusPlus14)
+      return Invalid(S, OpPC);
+  }
+
   const T &Value = Ptr.deref<T>();
   T Result;
 
@@ -2067,8 +2074,12 @@ inline bool CallVirt(InterpState &S, CodePtr OpPC, const Function *Func,
   size_t ThisOffset = ArgSize - (Func->hasRVO() ? primSize(PT_Ptr) : 0);
   Pointer &ThisPtr = S.Stk.peek<Pointer>(ThisOffset);
 
-  const CXXRecordDecl *DynamicDecl =
-      ThisPtr.getDeclDesc()->getType()->getAsCXXRecordDecl();
+  QualType DynamicType = ThisPtr.getDeclDesc()->getType();
+  const CXXRecordDecl *DynamicDecl;
+  if (DynamicType->isPointerType() || DynamicType->isReferenceType())
+    DynamicDecl = DynamicType->getPointeeCXXRecordDecl();
+  else
+    DynamicDecl = ThisPtr.getDeclDesc()->getType()->getAsCXXRecordDecl();
   const auto *StaticDecl = cast<CXXRecordDecl>(Func->getParentDecl());
   const auto *InitialFunction = cast<CXXMethodDecl>(Func->getDecl());
   const CXXMethodDecl *Overrider = S.getContext().getOverridingFunction(

clang/lib/AST/Interp/Opcodes.td

@@ -563,10 +563,10 @@ def Inv: Opcode {
 }
 
 // Increment and decrement.
-def Inc: IntegerOpcode;
-def IncPop : IntegerOpcode;
-def Dec: IntegerOpcode;
-def DecPop: IntegerOpcode;
+def Inc: AluOpcode;
+def IncPop : AluOpcode;
+def Dec: AluOpcode;
+def DecPop: AluOpcode;
 
 // Float increment and decrement.
 def Incf: FloatOpcode;

clang/lib/Driver/ToolChains/CommonArgs.cpp

@@ -2795,10 +2795,6 @@ void tools::addOpenMPDeviceRTL(const Driver &D,
                                const ToolChain &HostTC) {
   SmallVector<StringRef, 8> LibraryPaths;
 
-  // Check all of the standard library search paths used by the compiler.
-  for (const auto &LibPath : HostTC.getFilePaths())
-    LibraryPaths.emplace_back(LibPath);
-
   // Add user defined library paths from LIBRARY_PATH.
   std::optional<std::string> LibPath =
       llvm::sys::Process::GetEnv("LIBRARY_PATH");
@@ -2810,6 +2806,10 @@ void tools::addOpenMPDeviceRTL(const Driver &D,
       LibraryPaths.emplace_back(Path.trim());
   }
 
+  // Check all of the standard library search paths used by the compiler.
+  for (const auto &LibPath : HostTC.getFilePaths())
+    LibraryPaths.emplace_back(LibPath);
+
   OptSpecifier LibomptargetBCPathOpt =
       Triple.isAMDGCN() ? options::OPT_libomptarget_amdgpu_bc_path_EQ
                         : options::OPT_libomptarget_nvptx_bc_path_EQ;

clang/lib/Sema/SemaDecl.cpp

@@ -2044,7 +2044,8 @@ static bool ShouldDiagnoseUnusedDecl(const LangOptions &LangOpts,
           return false;
 
         if (Init) {
-          const auto *Construct = dyn_cast<CXXConstructExpr>(Init);
+          const auto *Construct =
+              dyn_cast<CXXConstructExpr>(Init->IgnoreImpCasts());
           if (Construct && !Construct->isElidable()) {
             const CXXConstructorDecl *CD = Construct->getConstructor();
             if (!CD->isTrivial() && !RD->hasAttr<WarnUnusedAttr>() &&

clang/lib/Sema/SemaStmt.cpp

@@ -527,6 +527,13 @@ Sema::ActOnCaseStmt(SourceLocation CaseLoc, ExprResult LHSVal,
     return StmtError();
   }
 
+  if (LangOpts.OpenACC &&
+      getCurScope()->isInOpenACCComputeConstructBeforeSwitch()) {
+    Diag(CaseLoc, diag::err_acc_branch_in_out_compute_construct)
+        << /*branch*/ 0 << /*into*/ 1;
+    return StmtError();
+  }
+
   auto *CS = CaseStmt::Create(Context, LHSVal.get(), RHSVal.get(),
                               CaseLoc, DotDotDotLoc, ColonLoc);
   getCurFunction()->SwitchStack.back().getPointer()->addSwitchCase(CS);
@@ -546,6 +553,13 @@ Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc,
     return SubStmt;
   }
 
+  if (LangOpts.OpenACC &&
+      getCurScope()->isInOpenACCComputeConstructBeforeSwitch()) {
+    Diag(DefaultLoc, diag::err_acc_branch_in_out_compute_construct)
+        << /*branch*/ 0 << /*into*/ 1;
+    return StmtError();
+  }
+
   DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt);
   getCurFunction()->SwitchStack.back().getPointer()->addSwitchCase(DS);
   return DS;

clang/lib/Sema/SemaTemplate.cpp

@@ -3141,12 +3141,14 @@ bool Sema::CheckTemplateParameterList(TemplateParameterList *NewParams,
            diag::note_template_param_prev_default_arg_in_other_module)
           << PrevModuleName;
       Invalid = true;
-    } else if (MissingDefaultArg && TPC != TPC_FunctionTemplate) {
-      // C++ [temp.param]p11:
-      //   If a template-parameter of a class template has a default
-      //   template-argument, each subsequent template-parameter shall either
-      //   have a default template-argument supplied or be a template parameter
-      //   pack.
+    } else if (MissingDefaultArg &&
+               (TPC == TPC_ClassTemplate || TPC == TPC_FriendClassTemplate ||
+                TPC == TPC_VarTemplate || TPC == TPC_TypeAliasTemplate)) {
+      // C++ 23[temp.param]p14:
+      // If a template-parameter of a class template, variable template, or
+      // alias template has a default template argument, each subsequent
+      // template-parameter shall either have a default template argument
+      // supplied or be a template parameter pack.
       Diag((*NewParam)->getLocation(),
            diag::err_template_param_default_arg_missing);
       Diag(PreviousDefaultArgLoc, diag::note_template_param_prev_default_arg);

clang/test/AST/Interp/functions.cpp

@@ -555,3 +555,13 @@ namespace Local {
     return t;
   }
 }
+
+namespace VariadicOperator {
+  struct Callable {
+    float& operator()(...);
+  };
+
+  void test_callable(Callable c) {
+    float &fr = c(10);
+  }
+}

clang/test/AST/Interp/literals.cpp

@@ -1131,3 +1131,40 @@ namespace nullptrsub {
     f = (char *)((char *)0 - (char *)0);
   }
 }
+
+namespace incdecbool {
+#if __cplusplus >= 201402L
+  constexpr bool incb(bool c) {
+    if (!c)
+      ++c;
+    else {++c; c++; }
+#if __cplusplus >= 202002L
+    // both-error@-3 {{ISO C++17 does not allow incrementing expression of type bool}}
+    // both-error@-3 2{{ISO C++17 does not allow incrementing expression of type bool}}
+#else
+    // both-warning@-6 {{incrementing expression of type bool is deprecated and incompatible with C++17}}
+#endif
+    return c;
+  }
+  static_assert(incb(false), "");
+  static_assert(incb(true), "");
+  static_assert(incb(true) == 1, "");
+#endif
+
+
+#if __cplusplus == 201103L
+  constexpr bool foo() { // both-error {{never produces a constant expression}}
+    bool b = true; // both-warning {{variable declaration in a constexpr function is a C++14 extension}}
+    b++; // both-warning {{incrementing expression of type bool is deprecated and incompatible with C++17}} \
+         // both-warning {{use of this statement in a constexpr function is a C++14 extension}} \
+         // both-note 2{{subexpression not valid in a constant expression}}
+
+    return b;
+  }
+  static_assert(foo() == 1, ""); // both-error {{not an integral constant expression}} \
+                                 // both-note {{in call to}}
+#endif
+
+
+
+}

clang/test/Driver/openmp-offload-gpu.c

@@ -156,21 +156,6 @@
 
 /// ###########################################################################
 
-/// Check that the warning is thrown when the libomptarget bitcode library is not found.
-/// Libomptarget requires sm_52 or newer so an sm_52 bitcode library should never exist.
-// RUN:   not %clang -### -fopenmp=libomp -fopenmp-targets=nvptx64-nvidia-cuda \
-// RUN:   -Xopenmp-target -march=sm_52 --cuda-path=%S/Inputs/CUDA_102/usr/local/cuda \
-// RUN:   -fopenmp-relocatable-target -save-temps %s 2>&1 \
-// RUN:   | FileCheck -check-prefix=CHK-BCLIB-WARN %s
-
-// CHK-BCLIB-WARN: no library 'libomptarget-nvptx-sm_52.bc' found in the default clang lib directory or in LIBRARY_PATH; use '--libomptarget-nvptx-bc-path' to specify nvptx bitcode library
-
-/// ###########################################################################
-
-/// Check -Xopenmp-target triggers error when an option requiring arguments is passed to it.
-// RUN:  not %clang -### -fopenmp=libomp -fopenmp-targets=powerpc64le-ibm-linux-gnu -Xopenmp-target -Xopenmp-target -mcpu=pwr8 %s 2>&1 \
-// RUN:   | FileCheck -check-prefix=CHK-FOPENMP-TARGET-NESTED-ERROR %s
-
 /// Check that the error is thrown when the libomptarget bitcode library does not exist.
 // RUN:   not %clang -### -fopenmp=libomp -fopenmp-targets=nvptx64-nvidia-cuda \
 // RUN:   -Xopenmp-target -march=sm_52 --cuda-path=%S/Inputs/CUDA_102/usr/local/cuda \