Factor out function to determine whether we're performing a template

instantiation.

In preparation for converting the template stack to a more general context
stack (so we can include context notes for other kinds of context).


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@295686 91177308-0d34-0410-b5e6-96231b3b80d8

Author: zygoloid

include/clang/Sema/Sema.h

@@ -7182,6 +7182,20 @@ class Sema {
     operator=(const InstantiatingTemplate&) = delete;
   };
 
+  /// Determine whether we are currently performing template instantiation.
+  bool inTemplateInstantiation() const {
+    return ActiveTemplateInstantiations.size() > NonInstantiationEntries;
+  }
+
+  void PrintContextStack() {
+    if (!ActiveTemplateInstantiations.empty() &&
+        ActiveTemplateInstantiations.back() !=
+            LastTemplateInstantiationErrorContext) {
+      PrintInstantiationStack();
+      LastTemplateInstantiationErrorContext =
+          ActiveTemplateInstantiations.back();
+    }
+  }
   void PrintInstantiationStack();
 
   /// \brief Determines whether we are currently in a context where

lib/Sema/Sema.cpp

@@ -327,7 +327,7 @@ bool Sema::makeUnavailableInSystemHeader(SourceLocation loc,
   if (!fn) return false;
 
   // If we're in template instantiation, it's an error.
-  if (!ActiveTemplateInstantiations.empty())
+  if (inTemplateInstantiation())
     return false;
 
   // If that function's not in a system header, it's an error.
@@ -1006,7 +1006,7 @@ void Sema::EmitCurrentDiagnostic(unsigned DiagID) {
   // and yet we also use the current diag ID on the DiagnosticsEngine. This has
   // been made more painfully obvious by the refactor that introduced this
   // function, but it is possible that the incoming argument can be
-  // eliminnated. If it truly cannot be (for example, there is some reentrancy
+  // eliminated. If it truly cannot be (for example, there is some reentrancy
   // issue I am not seeing yet), then there should at least be a clarifying
   // comment somewhere.
   if (Optional<TemplateDeductionInfo*> Info = isSFINAEContext()) {
@@ -1094,13 +1094,8 @@ void Sema::EmitCurrentDiagnostic(unsigned DiagID) {
   // that is different from the last template instantiation where
   // we emitted an error, print a template instantiation
   // backtrace.
-  if (!DiagnosticIDs::isBuiltinNote(DiagID) &&
-      !ActiveTemplateInstantiations.empty() &&
-      ActiveTemplateInstantiations.back()
-        != LastTemplateInstantiationErrorContext) {
-    PrintInstantiationStack();
-    LastTemplateInstantiationErrorContext = ActiveTemplateInstantiations.back();
-  }
+  if (!DiagnosticIDs::isBuiltinNote(DiagID))
+    PrintContextStack();
 }
 
 Sema::SemaDiagnosticBuilder

lib/Sema/SemaChecking.cpp

@@ -244,7 +244,7 @@ static bool SemaBuiltinSEHScopeCheck(Sema &SemaRef, CallExpr *TheCall,
   // Scopes aren't available during instantiation. Fortunately, builtin
   // functions cannot be template args so they cannot be formed through template
   // instantiation. Therefore checking once during the parse is sufficient.
-  if (!SemaRef.ActiveTemplateInstantiations.empty())
+  if (SemaRef.inTemplateInstantiation())
     return false;
 
   Scope *S = SemaRef.getCurScope();
@@ -6782,7 +6782,7 @@ void Sema::CheckMaxUnsignedZero(const CallExpr *Call,
   if (!Call || !FDecl) return;
 
   // Ignore template specializations and macros.
-  if (!ActiveTemplateInstantiations.empty()) return;
+  if (inTemplateInstantiation()) return;
   if (Call->getExprLoc().isMacroID()) return;
 
   // Only care about the one template argument, two function parameter std::max
@@ -8235,7 +8235,7 @@ bool HasEnumType(Expr *E) {
 
 void CheckTrivialUnsignedComparison(Sema &S, BinaryOperator *E) {
   // Disable warning in template instantiations.
-  if (!S.ActiveTemplateInstantiations.empty())
+  if (S.inTemplateInstantiation())
     return;
 
   BinaryOperatorKind op = E->getOpcode();
@@ -8265,7 +8265,7 @@ void DiagnoseOutOfRangeComparison(Sema &S, BinaryOperator *E, Expr *Constant,
                                   Expr *Other, const llvm::APSInt &Value,
                                   bool RhsConstant) {
   // Disable warning in template instantiations.
-  if (!S.ActiveTemplateInstantiations.empty())
+  if (S.inTemplateInstantiation())
     return;
 
   // TODO: Investigate using GetExprRange() to get tighter bounds
@@ -8703,7 +8703,7 @@ void DiagnoseFloatingImpCast(Sema &S, Expr *E, QualType T,
 
                              SourceLocation CContext) {
   const bool IsBool = T->isSpecificBuiltinType(BuiltinType::Bool);
-  const bool PruneWarnings = !S.ActiveTemplateInstantiations.empty();
+  const bool PruneWarnings = S.inTemplateInstantiation();
 
   Expr *InnerE = E->IgnoreParenImpCasts();
   // We also want to warn on, e.g., "int i = -1.234"
@@ -11314,7 +11314,7 @@ void Sema::DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
   if (Diags.isIgnored(diag::warn_sizeof_pointer_expr_memaccess, OpLoc))
     return;
 
-  if (!ActiveTemplateInstantiations.empty())
+  if (inTemplateInstantiation())
     return;
 
   // Strip parens and casts away.

lib/Sema/SemaDecl.cpp

@@ -3088,7 +3088,7 @@ bool Sema::MergeFunctionDecl(FunctionDecl *New, NamedDecl *&OldD,
         //   [...] A member shall not be declared twice in the
         //   member-specification, except that a nested class or member
         //   class template can be declared and then later defined.
-        if (ActiveTemplateInstantiations.empty()) {
+        if (!inTemplateInstantiation()) {
           unsigned NewDiag;
           if (isa<CXXConstructorDecl>(OldMethod))
             NewDiag = diag::err_constructor_redeclared;
@@ -9061,7 +9061,7 @@ bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
 
       // Warn that we did this, if we're not performing template instantiation.
       // In that case, we'll have warned already when the template was defined.
-      if (ActiveTemplateInstantiations.empty()) {
+      if (!inTemplateInstantiation()) {
         SourceLocation AddConstLoc;
         if (FunctionTypeLoc FTL = MD->getTypeSourceInfo()->getTypeLoc()
                 .IgnoreParens().getAs<FunctionTypeLoc>())
@@ -9918,8 +9918,8 @@ QualType Sema::deduceVarTypeFromInitializer(VarDecl *VDecl,
   // checks.
   // We only want to warn outside of template instantiations, though:
   // inside a template, the 'id' could have come from a parameter.
-  if (ActiveTemplateInstantiations.empty() && !DefaultedAnyToId &&
-      !IsInitCapture && !DeducedType.isNull() && DeducedType->isObjCIdType()) {
+  if (!inTemplateInstantiation() && !DefaultedAnyToId && !IsInitCapture &&
+      !DeducedType.isNull() && DeducedType->isObjCIdType()) {
     SourceLocation Loc = TSI->getTypeLoc().getBeginLoc();
     Diag(Loc, diag::warn_auto_var_is_id) << VN << Range;
   }
@@ -10821,7 +10821,7 @@ void Sema::CheckCompleteVariableDeclaration(VarDecl *var) {
   // Apply section attributes and pragmas to global variables.
   bool GlobalStorage = var->hasGlobalStorage();
   if (GlobalStorage && var->isThisDeclarationADefinition() &&
-      ActiveTemplateInstantiations.empty()) {
+      !inTemplateInstantiation()) {
     PragmaStack<StringLiteral *> *Stack = nullptr;
     int SectionFlags = ASTContext::PSF_Implicit | ASTContext::PSF_Read;
     if (var->getType().isConstQualified())
@@ -11472,7 +11472,7 @@ ParmVarDecl *Sema::BuildParmVarDeclForTypedef(DeclContext *DC,
 void Sema::DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters) {
   // Don't diagnose unused-parameter errors in template instantiations; we
   // will already have done so in the template itself.
-  if (!ActiveTemplateInstantiations.empty())
+  if (inTemplateInstantiation())
     return;
 
   for (const ParmVarDecl *Parameter : Parameters) {
@@ -11822,14 +11822,14 @@ Decl *Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, Decl *D,
   // captures during transformation of nested lambdas, it is necessary to
   // have the LSI properly restored.
   if (isGenericLambdaCallOperatorSpecialization(FD)) {
-    assert(ActiveTemplateInstantiations.size() &&
-      "There should be an active template instantiation on the stack "
-      "when instantiating a generic lambda!");
+    assert(inTemplateInstantiation() &&
+           "There should be an active template instantiation on the stack "
+           "when instantiating a generic lambda!");
     RebuildLambdaScopeInfo(cast<CXXMethodDecl>(D), *this);
-  }
-  else
+  } else {
     // Enter a new function scope
     PushFunctionScope();
+  }
 
   // Builtin functions cannot be defined.
   if (unsigned BuiltinID = FD->getBuiltinID()) {
@@ -12706,7 +12706,7 @@ bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous,
     if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous))
       isTemplate = Record->getDescribedClassTemplate();
 
-    if (!ActiveTemplateInstantiations.empty()) {
+    if (inTemplateInstantiation()) {
       // In a template instantiation, do not offer fix-its for tag mismatches
       // since they usually mess up the template instead of fixing the problem.
       Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch)

lib/Sema/SemaDeclAttr.cpp

@@ -1420,7 +1420,7 @@ static void handleNonNullAttr(Sema &S, Decl *D, const AttributeList &Attr) {
   // check if the attribute came from a macro expansion or a template
   // instantiation.
   if (NonNullArgs.empty() && Attr.getLoc().isFileID() &&
-      S.ActiveTemplateInstantiations.empty()) {
+      !S.inTemplateInstantiation()) {
     bool AnyPointers = isFunctionOrMethodVariadic(D);
     for (unsigned I = 0, E = getFunctionOrMethodNumParams(D);
          I != E && !AnyPointers; ++I) {

lib/Sema/SemaDeclCXX.cpp

@@ -12970,7 +12970,7 @@ checkLiteralOperatorTemplateParameterList(Sema &SemaRef,
           PmArgs->getType()->getAs<TemplateTypeParmType>();
       if (TArgs && TArgs->getDepth() == PmType->getDepth() &&
           TArgs->getIndex() == PmType->getIndex()) {
-        if (SemaRef.ActiveTemplateInstantiations.empty())
+        if (!SemaRef.inTemplateInstantiation())
           SemaRef.Diag(TpDecl->getLocation(),
                        diag::ext_string_literal_operator_template);
         return false;

lib/Sema/SemaExpr.cpp

@@ -1441,7 +1441,7 @@ Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc,
 
   // The controlling expression is an unevaluated operand, so side effects are
   // likely unintended.
-  if (ActiveTemplateInstantiations.empty() &&
+  if (!inTemplateInstantiation() &&
       ControllingExpr->HasSideEffects(Context, false))
     Diag(ControllingExpr->getExprLoc(),
          diag::warn_side_effects_unevaluated_context);
@@ -3695,7 +3695,7 @@ bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
   // The operand for sizeof and alignof is in an unevaluated expression context,
   // so side effects could result in unintended consequences.
   if ((ExprKind == UETT_SizeOf || ExprKind == UETT_AlignOf) &&
-      ActiveTemplateInstantiations.empty() && E->HasSideEffects(Context, false))
+      !inTemplateInstantiation() && E->HasSideEffects(Context, false))
     Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context);
 
   if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(),
@@ -9259,7 +9259,7 @@ QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
       !(LHSType->isBlockPointerType() && IsRelational) &&
       !LHS.get()->getLocStart().isMacroID() &&
       !RHS.get()->getLocStart().isMacroID() &&
-      ActiveTemplateInstantiations.empty()) {
+      !inTemplateInstantiation()) {
     // For non-floating point types, check for self-comparisons of the form
     // x == x, x != x, x < x, etc.  These always evaluate to a constant, and
     // often indicate logic errors in the program.
@@ -9731,8 +9731,7 @@ QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
   // For non-floating point types, check for self-comparisons of the form
   // x == x, x != x, x < x, etc.  These always evaluate to a constant, and
   // often indicate logic errors in the program.
-  if (!LHSType->hasFloatingRepresentation() &&
-      ActiveTemplateInstantiations.empty()) {
+  if (!LHSType->hasFloatingRepresentation() && !inTemplateInstantiation()) {
     if (DeclRefExpr* DRL
           = dyn_cast<DeclRefExpr>(LHS.get()->IgnoreParenImpCasts()))
       if (DeclRefExpr* DRR
@@ -9820,7 +9819,7 @@ inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
       !LHS.get()->getType()->isBooleanType() &&
       RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
       // Don't warn in macros or template instantiations.
-      !Loc.isMacroID() && ActiveTemplateInstantiations.empty()) {
+      !Loc.isMacroID() && !inTemplateInstantiation()) {
     // If the RHS can be constant folded, and if it constant folds to something
     // that isn't 0 or 1 (which indicate a potential logical operation that
     // happened to fold to true/false) then warn.
@@ -10356,7 +10355,7 @@ void Sema::DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc) {
     return;
 
   // Don't warn in template instantiations.
-  if (!ActiveTemplateInstantiations.empty())
+  if (inTemplateInstantiation())
     return;
 
   // Scope isn't fine-grained enough to whitelist the specific cases, so
@@ -10951,7 +10950,7 @@ static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
 /// suppressed in the event of macro expansions.
 static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
                                    SourceLocation OpLoc) {
-  if (!S.ActiveTemplateInstantiations.empty())
+  if (S.inTemplateInstantiation())
     return;
   if (OpLoc.isInvalid() || OpLoc.isMacroID())
     return;

lib/Sema/SemaExprCXX.cpp

@@ -459,7 +459,7 @@ ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
   if (E->getType()->isVariablyModifiedType())
     return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
                      << E->getType());
-  else if (ActiveTemplateInstantiations.empty() &&
+  else if (!inTemplateInstantiation() &&
            E->HasSideEffects(Context, WasEvaluated)) {
     // The expression operand for typeid is in an unevaluated expression
     // context, so side effects could result in unintended consequences.
@@ -979,7 +979,7 @@ QualType Sema::getCurrentThisType() {
   }
 
   if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
-      !ActiveTemplateInstantiations.empty()) {
+      inTemplateInstantiation()) {
 
     assert(isa<CXXRecordDecl>(DC) &&
            "Trying to get 'this' type from static method?");
@@ -6817,8 +6817,7 @@ ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
   // The operand may have been modified when checking the placeholder type.
   Operand = R.get();
 
-  if (ActiveTemplateInstantiations.empty() &&
-      Operand->HasSideEffects(Context, false)) {
+  if (!inTemplateInstantiation() && Operand->HasSideEffects(Context, false)) {
     // The expression operand for noexcept is in an unevaluated expression
     // context, so side effects could result in unintended consequences.
     Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);

lib/Sema/SemaInit.cpp

@@ -902,7 +902,7 @@ static void warnBracedScalarInit(Sema &S, const InitializedEntity &Entity,
   // Don't warn during template instantiation. If the initialization was
   // non-dependent, we warned during the initial parse; otherwise, the
   // type might not be scalar in some uses of the template.
-  if (!S.ActiveTemplateInstantiations.empty())
+  if (S.inTemplateInstantiation())
     return;
 
   unsigned DiagID = 0;
@@ -6249,7 +6249,7 @@ static void CheckMoveOnConstruction(Sema &S, const Expr *InitExpr,
   if (!InitExpr)
     return;
 
-  if (!S.ActiveTemplateInstantiations.empty())
+  if (S.inTemplateInstantiation())
     return;
 
   QualType DestType = InitExpr->getType();

lib/Sema/SemaLambda.cpp

@@ -312,7 +312,7 @@ Sema::getCurrentMangleNumberContext(const DeclContext *DC,
   //   In the following contexts [...] the one-definition rule requires closure
   //   types in different translation units to "correspond":
   bool IsInNonspecializedTemplate =
-    !ActiveTemplateInstantiations.empty() || CurContext->isDependentContext();
+      inTemplateInstantiation() || CurContext->isDependentContext();
   switch (Kind) {
   case Normal: {
     //  -- the bodies of non-exported nonspecialized template functions

lib/Sema/SemaOverload.cpp

@@ -11491,7 +11491,7 @@ DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc,
                        TemplateArgumentListInfo *ExplicitTemplateArgs,
                        ArrayRef<Expr *> Args,
                        bool *DoDiagnoseEmptyLookup = nullptr) {
-  if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty())
+  if (!SemaRef.inTemplateInstantiation() || !SS.isEmpty())
     return false;
 
   for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) {

lib/Sema/SemaStmt.cpp

@@ -1810,7 +1810,7 @@ Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc,
 
         D->setType(FirstType);
 
-        if (ActiveTemplateInstantiations.empty()) {
+        if (!inTemplateInstantiation()) {
           SourceLocation Loc =
               D->getTypeSourceInfo()->getTypeLoc().getBeginLoc();
           Diag(Loc, diag::warn_auto_var_is_id)

lib/Sema/SemaTemplate.cpp

@@ -6775,7 +6775,7 @@ static bool CheckTemplateSpecializationScope(Sema &S,
       // Do not warn for class scope explicit specialization during
       // instantiation, warning was already emitted during pattern
       // semantic analysis.
-      if (!S.ActiveTemplateInstantiations.size())
+      if (!S.inTemplateInstantiation())
         S.Diag(Loc, diag::ext_function_specialization_in_class)
           << Specialized;
     } else {

lib/Sema/SemaType.cpp

@@ -742,7 +742,7 @@ static void diagnoseAndRemoveTypeQualifiers(Sema &S, const DeclSpec &DS,
     if (!(RemoveTQs & Qual.first))
       continue;
 
-    if (S.ActiveTemplateInstantiations.empty()) {
+    if (!S.inTemplateInstantiation()) {
       if (TypeQuals & Qual.first)
         S.Diag(Qual.second, DiagID)
           << DeclSpec::getSpecifierName(Qual.first) << TypeSoFar