Move Sema::VerifyIntegerConstantExpression() and

Sema::ConvertToIntegralOrEnumerationType() from PartialDiagnostics to
abstract "diagnoser" classes. Not much of a win here, but we're
-several PartialDiagnostics.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156217 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Basic/Diagnostic.h

@@ -781,13 +781,17 @@ class DiagnosticBuilder {
 
   void operator=(const DiagnosticBuilder&); // DO NOT IMPLEMENT
   friend class DiagnosticsEngine;
+  
+  DiagnosticBuilder()
+    : DiagObj(0), NumArgs(0), NumRanges(0), NumFixits(0), IsActive(false) { }
+
   explicit DiagnosticBuilder(DiagnosticsEngine *diagObj)
     : DiagObj(diagObj), NumArgs(0), NumRanges(0), NumFixits(0), IsActive(true) {
     assert(diagObj && "DiagnosticBuilder requires a valid DiagnosticsEngine!");
   }
 
   friend class PartialDiagnostic;
-
+  
 protected:
   void FlushCounts() {
     DiagObj->NumDiagArgs = NumArgs;
@@ -841,6 +845,11 @@ public:
     NumFixits = D.NumFixits;
   }
 
+  /// \brief Retrieve an empty diagnostic builder.
+  static DiagnosticBuilder getEmpty() {
+    return DiagnosticBuilder();
+  }
+
   /// Destructor - The dtor emits the diagnostic.
   ~DiagnosticBuilder() {
     Emit();

include/clang/Basic/DiagnosticSemaKinds.td

@@ -1463,6 +1463,8 @@ def err_attribute_bad_neon_vector_size : Error<
   "Neon vector size must be 64 or 128 bits">;
 def err_attribute_argument_not_int : Error<
   "'%0' attribute requires integer constant">;
+def err_aligned_attribute_argument_not_int : Error<
+  "'aligned' attribute requires integer constant">;
 def err_attribute_argument_not_class : Error<
   "%0 attribute requires arguments that are class type or point to class type">;
 def err_attribute_first_argument_not_int_or_bool : Error<

include/clang/Sema/Sema.h

@@ -1715,16 +1715,59 @@ public:
   ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
                                               llvm::APSInt &Value, CCEKind CCE);
 
+  /// \brief Abstract base class used to diagnose problems that occur while
+  /// trying to convert an expression to integral or enumeration type.
+  class ICEConvertDiagnoser {
+  public:
+    bool Suppress;
+    bool SuppressConversion;
+    
+    ICEConvertDiagnoser(bool Suppress = false,
+                        bool SuppressConversion = false)
+      : Suppress(Suppress), SuppressConversion(SuppressConversion) { }
+    
+    /// \brief Emits a diagnostic complaining that the expression does not have
+    /// integral or enumeration type.
+    virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
+                                             QualType T) = 0;
+    
+    /// \brief Emits a diagnostic when the expression has incomplete class type.
+    virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
+                                                 QualType T) = 0;
+    
+    /// \brief Emits a diagnostic when the only matching conversion function
+    /// is explicit.
+    virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
+                                                   QualType T,
+                                                   QualType ConvTy) = 0;
+
+    /// \brief Emits a note for the explicit conversion function.
+    virtual DiagnosticBuilder
+    noteExplicitConv(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
+
+    /// \brief Emits a diagnostic when there are multiple possible conversion
+    /// functions.
+    virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                QualType T) = 0;
+
+    /// \brief Emits a note for one of the candidate conversions.
+    virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
+                                            QualType ConvTy) = 0;
+
+    /// \brief Emits a diagnostic when we picked a conversion function
+    /// (for cases when we are not allowed to pick a conversion function).
+    virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
+                                                 QualType T,
+                                                 QualType ConvTy) = 0;
+    
+    virtual ~ICEConvertDiagnoser() {}
+  };
+
   ExprResult
   ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *FromE,
-                                     const PartialDiagnostic &NotIntDiag,
-                                     const PartialDiagnostic &IncompleteDiag,
-                                     const PartialDiagnostic &ExplicitConvDiag,
-                                     const PartialDiagnostic &ExplicitConvNote,
-                                     const PartialDiagnostic &AmbigDiag,
-                                     const PartialDiagnostic &AmbigNote,
-                                     const PartialDiagnostic &ConvDiag,
+                                     ICEConvertDiagnoser &Diagnoser,
                                      bool AllowScopedEnumerations);
+
   enum ObjCSubscriptKind {
     OS_Array,
     OS_Dictionary,
@@ -6738,20 +6781,29 @@ public:
   /// in the global scope.
   bool CheckObjCDeclScope(Decl *D);
 
+  /// \brief Abstract base class used for diagnosing integer constant
+  /// expression violations.
+  class VerifyICEDiagnoser {
+  public:
+    bool Suppress;
+    
+    VerifyICEDiagnoser(bool Suppress = false) : Suppress(Suppress) { }
+    
+    virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) =0;
+    virtual void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR);
+    virtual ~VerifyICEDiagnoser() { }
+  };
+    
   /// VerifyIntegerConstantExpression - Verifies that an expression is an ICE,
   /// and reports the appropriate diagnostics. Returns false on success.
   /// Can optionally return the value of the expression.
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                             const PartialDiagnostic &Diag,
-                                             bool AllowFold,
-                                             const PartialDiagnostic &FoldDiag);
+                                             VerifyICEDiagnoser &Diagnoser,
+                                             bool AllowFold = true);
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                             const PartialDiagnostic &Diag,
-                                             bool AllowFold = true) {
-    return VerifyIntegerConstantExpression(E, Result, Diag, AllowFold,
-                                           PDiag(0));
-  }
-  ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result = 0);
+                                             unsigned DiagID,
+                                             bool AllowFold = true);
+  ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result=0);
 
   /// VerifyBitField - verifies that a bit field expression is an ICE and has
   /// the correct width, and that the field type is valid.

lib/Sema/SemaDeclAttr.cpp

@@ -2709,10 +2709,10 @@ void Sema::AddAlignedAttr(SourceRange AttrRange, Decl *D, Expr *E) {
   SourceLocation AttrLoc = AttrRange.getBegin();
   // FIXME: Cache the number on the Attr object?
   llvm::APSInt Alignment(32);
-  ExprResult ICE =
-    VerifyIntegerConstantExpression(E, &Alignment,
-      PDiag(diag::err_attribute_argument_not_int) << "aligned",
-      /*AllowFold*/ false);
+  ExprResult ICE
+    = VerifyIntegerConstantExpression(E, &Alignment,
+        diag::err_aligned_attribute_argument_not_int,
+        /*AllowFold*/ false);
   if (ICE.isInvalid())
     return;
   if (!llvm::isPowerOf2_64(Alignment.getZExtValue())) {

lib/Sema/SemaDeclCXX.cpp

@@ -9906,7 +9906,7 @@ Decl *Sema::ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
 
     llvm::APSInt Cond;
     if (VerifyIntegerConstantExpression(Converted.get(), &Cond,
-          PDiag(diag::err_static_assert_expression_is_not_constant),
+          diag::err_static_assert_expression_is_not_constant,
           /*AllowFold=*/false).isInvalid())
       return 0;
 
@@ -11302,7 +11302,7 @@ Sema::checkExceptionSpecification(ExceptionSpecificationType EST,
       
       if (!NoexceptExpr->isValueDependent())
         NoexceptExpr = VerifyIntegerConstantExpression(NoexceptExpr, 0,
-                         PDiag(diag::err_noexcept_needs_constant_expression),
+                         diag::err_noexcept_needs_constant_expression,
                          /*AllowFold*/ false).take();
       EPI.NoexceptExpr = NoexceptExpr;
     }

lib/Sema/SemaExpr.cpp

@@ -8868,8 +8868,9 @@ ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
   } else {
     // The conditional expression is required to be a constant expression.
     llvm::APSInt condEval(32);
-    ExprResult CondICE = VerifyIntegerConstantExpression(CondExpr, &condEval,
-      PDiag(diag::err_typecheck_choose_expr_requires_constant), false);
+    ExprResult CondICE
+      = VerifyIntegerConstantExpression(CondExpr, &condEval,
+          diag::err_typecheck_choose_expr_requires_constant, false);
     if (CondICE.isInvalid())
       return ExprError();
     CondExpr = CondICE.take();
@@ -9452,15 +9453,44 @@ bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
 
 ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
                                                  llvm::APSInt *Result) {
-  return VerifyIntegerConstantExpression(E, Result,
-      PDiag(diag::err_expr_not_ice) << LangOpts.CPlusPlus);
+  class SimpleICEDiagnoser : public VerifyICEDiagnoser {
+  public:
+    virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
+      S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus << SR;
+    }
+  } Diagnoser;
+  
+  return VerifyIntegerConstantExpression(E, Result, Diagnoser);
+}
+
+ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
+                                                 llvm::APSInt *Result,
+                                                 unsigned DiagID,
+                                                 bool AllowFold) {
+  class IDDiagnoser : public VerifyICEDiagnoser {
+    unsigned DiagID;
+    
+  public:
+    IDDiagnoser(unsigned DiagID)
+      : VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
+    
+    virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
+      S.Diag(Loc, DiagID) << SR;
+    }
+  } Diagnoser(DiagID);
+  
+  return VerifyIntegerConstantExpression(E, Result, Diagnoser, AllowFold);
+}
+
+void Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc,
+                                            SourceRange SR) {
+  S.Diag(Loc, diag::ext_expr_not_ice) << SR << S.LangOpts.CPlusPlus;
 }
 
 ExprResult
 Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
-                                      const PartialDiagnostic &NotIceDiag,
-                                      bool AllowFold,
-                                      const PartialDiagnostic &FoldDiag) {
+                                      VerifyICEDiagnoser &Diagnoser,
+                                      bool AllowFold) {
   SourceLocation DiagLoc = E->getLocStart();
 
   if (getLangOpts().CPlusPlus0x) {
@@ -9470,23 +9500,111 @@ Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
     //   have a single non-explicit conversion function to an integral or
     //   unscoped enumeration type
     ExprResult Converted;
-    if (NotIceDiag.getDiagID()) {
-      Converted = ConvertToIntegralOrEnumerationType(
-        DiagLoc, E,
-        PDiag(diag::err_ice_not_integral),
-        PDiag(diag::err_ice_incomplete_type),
-        PDiag(diag::err_ice_explicit_conversion),
-        PDiag(diag::note_ice_conversion_here),
-        PDiag(diag::err_ice_ambiguous_conversion),
-        PDiag(diag::note_ice_conversion_here),
-        PDiag(0),
-        /*AllowScopedEnumerations*/ false);
+    if (!Diagnoser.Suppress) {
+      class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
+      public:
+        CXX11ConvertDiagnoser() : ICEConvertDiagnoser(false, true) { }
+        
+        virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
+                                                 QualType T) {
+          return S.Diag(Loc, diag::err_ice_not_integral) << T;
+        }
+        
+        virtual DiagnosticBuilder diagnoseIncomplete(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T) {
+          return S.Diag(Loc, diag::err_ice_incomplete_type) << T;
+        }
+        
+        virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S,
+                                                       SourceLocation Loc,
+                                                       QualType T,
+                                                       QualType ConvTy) {
+          return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy;
+        }
+        
+        virtual DiagnosticBuilder noteExplicitConv(Sema &S,
+                                                   CXXConversionDecl *Conv,
+                                                   QualType ConvTy) {
+          return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
+                   << ConvTy->isEnumeralType() << ConvTy;
+        }
+        
+        virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                    QualType T) {
+          return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T;
+        }
+        
+        virtual DiagnosticBuilder noteAmbiguous(Sema &S,
+                                                CXXConversionDecl *Conv,
+                                                QualType ConvTy) {
+          return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
+                   << ConvTy->isEnumeralType() << ConvTy;
+        }
+        
+        virtual DiagnosticBuilder diagnoseConversion(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T,
+                                                     QualType ConvTy) {
+          return DiagnosticBuilder::getEmpty();
+        }
+      } ConvertDiagnoser;
+
+      Converted = ConvertToIntegralOrEnumerationType(DiagLoc, E,
+                                                     ConvertDiagnoser,
+                                             /*AllowScopedEnumerations*/ false);
     } else {
       // The caller wants to silently enquire whether this is an ICE. Don't
       // produce any diagnostics if it isn't.
-      Converted = ConvertToIntegralOrEnumerationType(
-        DiagLoc, E, PDiag(), PDiag(), PDiag(), PDiag(),
-        PDiag(), PDiag(), PDiag(), false);
+      class SilentICEConvertDiagnoser : public ICEConvertDiagnoser {
+      public:
+        SilentICEConvertDiagnoser() : ICEConvertDiagnoser(true, true) { }
+        
+        virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
+                                                 QualType T) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder diagnoseIncomplete(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S,
+                                                       SourceLocation Loc,
+                                                       QualType T,
+                                                       QualType ConvTy) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder noteExplicitConv(Sema &S,
+                                                   CXXConversionDecl *Conv,
+                                                   QualType ConvTy) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                    QualType T) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder noteAmbiguous(Sema &S,
+                                                CXXConversionDecl *Conv,
+                                                QualType ConvTy) {
+          return DiagnosticBuilder::getEmpty();
+        }
+        
+        virtual DiagnosticBuilder diagnoseConversion(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T,
+                                                     QualType ConvTy) {
+          return DiagnosticBuilder::getEmpty();
+        }
+      } ConvertDiagnoser;
+      
+      Converted = ConvertToIntegralOrEnumerationType(DiagLoc, E,
+                                                     ConvertDiagnoser, false);
     }
     if (Converted.isInvalid())
       return Converted;
@@ -9495,8 +9613,8 @@ Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
       return ExprError();
   } else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
     // An ICE must be of integral or unscoped enumeration type.
-    if (NotIceDiag.getDiagID())
-      Diag(DiagLoc, NotIceDiag) << E->getSourceRange();
+    if (!Diagnoser.Suppress)
+      Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
     return ExprError();
   }
 
@@ -9536,8 +9654,8 @@ Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
   }
 
   if (!Folded || !AllowFold) {
-    if (NotIceDiag.getDiagID()) {
-      Diag(DiagLoc, NotIceDiag) << E->getSourceRange();
+    if (!Diagnoser.Suppress) {
+      Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
       for (unsigned I = 0, N = Notes.size(); I != N; ++I)
         Diag(Notes[I].first, Notes[I].second);
     }
@@ -9545,11 +9663,7 @@ Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
     return ExprError();
   }
 
-  if (FoldDiag.getDiagID())
-    Diag(DiagLoc, FoldDiag) << E->getSourceRange();
-  else
-    Diag(DiagLoc, diag::ext_expr_not_ice)
-      << E->getSourceRange() << LangOpts.CPlusPlus;
+  Diagnoser.diagnoseFold(*this, DiagLoc, E->getSourceRange());
   for (unsigned I = 0, N = Notes.size(); I != N; ++I)
     Diag(Notes[I].first, Notes[I].second);
 

lib/Sema/SemaExprCXX.cpp

@@ -982,8 +982,10 @@ Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
       DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
       if (Expr *NumElts = (Expr *)Array.NumElts) {
         if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
-          Array.NumElts = VerifyIntegerConstantExpression(NumElts, 0,
-            PDiag(diag::err_new_array_nonconst)).take();
+          Array.NumElts
+            = VerifyIntegerConstantExpression(NumElts, 0,
+                                              diag::err_new_array_nonconst)
+                .take();
           if (!Array.NumElts)
             return ExprError();
         }
@@ -1148,19 +1150,64 @@ Sema::BuildCXXNew(SourceLocation StartLoc, bool UseGlobal,
   //   enumeration type, or a class type for which a single non-explicit
   //   conversion function to integral or unscoped enumeration type exists.
   if (ArraySize && !ArraySize->isTypeDependent()) {
-    ExprResult ConvertedSize = ConvertToIntegralOrEnumerationType(
-      StartLoc, ArraySize,
-      PDiag(diag::err_array_size_not_integral) << getLangOpts().CPlusPlus0x,
-      PDiag(diag::err_array_size_incomplete_type)
-        << ArraySize->getSourceRange(),
-      PDiag(diag::err_array_size_explicit_conversion),
-      PDiag(diag::note_array_size_conversion),
-      PDiag(diag::err_array_size_ambiguous_conversion),
-      PDiag(diag::note_array_size_conversion),
-      PDiag(getLangOpts().CPlusPlus0x ?
-              diag::warn_cxx98_compat_array_size_conversion :
-              diag::ext_array_size_conversion),
-      /*AllowScopedEnumerations*/ false);
+    class SizeConvertDiagnoser : public ICEConvertDiagnoser {
+      Expr *ArraySize;
+      
+    public:
+      SizeConvertDiagnoser(Expr *ArraySize)
+        : ICEConvertDiagnoser(false, false), ArraySize(ArraySize) { }
+      
+      virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
+                                               QualType T) {
+        return S.Diag(Loc, diag::err_array_size_not_integral)
+                 << S.getLangOpts().CPlusPlus0x << T;
+      }
+      
+      virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
+                                                   QualType T) {
+        return S.Diag(Loc, diag::err_array_size_incomplete_type)
+                 << T << ArraySize->getSourceRange();
+      }
+      
+      virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S,
+                                                     SourceLocation Loc,
+                                                     QualType T,
+                                                     QualType ConvTy) {
+        return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
+      }
+      
+      virtual DiagnosticBuilder noteExplicitConv(Sema &S,
+                                                 CXXConversionDecl *Conv,
+                                                 QualType ConvTy) {
+        return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
+                 << ConvTy->isEnumeralType() << ConvTy;
+      }
+      
+      virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                  QualType T) {
+        return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
+      }
+      
+      virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
+                                              QualType ConvTy) {
+        return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
+                 << ConvTy->isEnumeralType() << ConvTy;
+      }
+      
+      virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
+                                                   QualType T,
+                                                   QualType ConvTy) {
+        return S.Diag(Loc,
+                      S.getLangOpts().CPlusPlus0x
+                        ? diag::warn_cxx98_compat_array_size_conversion
+                        : diag::ext_array_size_conversion)
+                 << T << ConvTy->isEnumeralType() << ConvTy;
+      }
+    } SizeDiagnoser(ArraySize);
+
+    ExprResult ConvertedSize
+      = ConvertToIntegralOrEnumerationType(StartLoc, ArraySize, SizeDiagnoser,
+                                           /*AllowScopedEnumerations*/ false);
     if (ConvertedSize.isInvalid())
       return ExprError();
 
@@ -3610,7 +3657,7 @@ static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
     llvm::APSInt Value;
     uint64_t Dim;
     if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
-          Self.PDiag(diag::err_dimension_expr_not_constant_integer),
+          diag::err_dimension_expr_not_constant_integer,
           false).isInvalid())
       return 0;
     if (Value.isSigned() && Value.isNegative()) {

lib/Sema/SemaOverload.cpp

@@ -5025,13 +5025,7 @@ static bool isIntegralOrEnumerationType(QualType T, bool AllowScopedEnum) {
 /// successful.
 ExprResult
 Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
-                                         const PartialDiagnostic &NotIntDiag,
-                                       const PartialDiagnostic &IncompleteDiag,
-                                     const PartialDiagnostic &ExplicitConvDiag,
-                                     const PartialDiagnostic &ExplicitConvNote,
-                                         const PartialDiagnostic &AmbigDiag,
-                                         const PartialDiagnostic &AmbigNote,
-                                         const PartialDiagnostic &ConvDiag,
+                                         ICEConvertDiagnoser &Diagnoser,
                                          bool AllowScopedEnumerations) {
   // We can't perform any more checking for type-dependent expressions.
   if (From->isTypeDependent())
@@ -5055,22 +5049,23 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
   // expression of integral or enumeration type.
   const RecordType *RecordTy = T->getAs<RecordType>();
   if (!RecordTy || !getLangOpts().CPlusPlus) {
-    if (NotIntDiag.getDiagID())
-      Diag(Loc, NotIntDiag) << T << From->getSourceRange();
+    if (!Diagnoser.Suppress)
+      Diagnoser.diagnoseNotInt(*this, Loc, T) << From->getSourceRange();
     return Owned(From);
   }
 
   // We must have a complete class type.
   struct TypeDiagnoserPartialDiag : TypeDiagnoser {
-    const PartialDiagnostic &PD;
+    ICEConvertDiagnoser &Diagnoser;
+    Expr *From;
     
-    TypeDiagnoserPartialDiag(const PartialDiagnostic &PD)
-      : TypeDiagnoser(PD.getDiagID() == 0), PD(PD) {}
+    TypeDiagnoserPartialDiag(ICEConvertDiagnoser &Diagnoser, Expr *From)
+      : TypeDiagnoser(Diagnoser.Suppress), Diagnoser(Diagnoser), From(From) {}
     
     virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) {
-      S.Diag(Loc, PD) << T;
+      Diagnoser.diagnoseIncomplete(S, Loc, T) << From->getSourceRange();
     }
-  } IncompleteDiagnoser(IncompleteDiag);
+  } IncompleteDiagnoser(Diagnoser, From);
 
   if (RequireCompleteType(Loc, T, IncompleteDiagnoser))
     return Owned(From);
@@ -5102,7 +5097,7 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
 
   switch (ViableConversions.size()) {
   case 0:
-    if (ExplicitConversions.size() == 1 && ExplicitConvDiag.getDiagID()) {
+    if (ExplicitConversions.size() == 1 && !Diagnoser.Suppress) {
       DeclAccessPair Found = ExplicitConversions[0];
       CXXConversionDecl *Conversion
         = cast<CXXConversionDecl>(Found->getUnderlyingDecl());
@@ -5114,14 +5109,12 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
       std::string TypeStr;
       ConvTy.getAsStringInternal(TypeStr, getPrintingPolicy());
 
-      Diag(Loc, ExplicitConvDiag)
-        << T << ConvTy
+      Diagnoser.diagnoseExplicitConv(*this, Loc, T, ConvTy)
         << FixItHint::CreateInsertion(From->getLocStart(),
                                       "static_cast<" + TypeStr + ">(")
         << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()),
                                       ")");
-      Diag(Conversion->getLocation(), ExplicitConvNote)
-        << ConvTy->isEnumeralType() << ConvTy;
+      Diagnoser.noteExplicitConv(*this, Conversion, ConvTy);
 
       // If we aren't in a SFINAE context, build a call to the
       // explicit conversion function.
@@ -5152,12 +5145,12 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
       = cast<CXXConversionDecl>(Found->getUnderlyingDecl());
     QualType ConvTy
       = Conversion->getConversionType().getNonReferenceType();
-    if (ConvDiag.getDiagID()) {
+    if (!Diagnoser.SuppressConversion) {
       if (isSFINAEContext())
         return ExprError();
 
-      Diag(Loc, ConvDiag)
-        << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange();
+      Diagnoser.diagnoseConversion(*this, Loc, T, ConvTy)
+        << From->getSourceRange();
     }
 
     ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion,
@@ -5173,24 +5166,24 @@ Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From,
   }
 
   default:
-    if (!AmbigDiag.getDiagID())
-      return Owned(From);
+    if (Diagnoser.Suppress)
+      return ExprError();
 
-    Diag(Loc, AmbigDiag)
-      << T << From->getSourceRange();
+    Diagnoser.diagnoseAmbiguous(*this, Loc, T) << From->getSourceRange();
     for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) {
       CXXConversionDecl *Conv
         = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl());
       QualType ConvTy = Conv->getConversionType().getNonReferenceType();
-      Diag(Conv->getLocation(), AmbigNote)
-        << ConvTy->isEnumeralType() << ConvTy;
+      Diagnoser.noteAmbiguous(*this, Conv, ConvTy);
     }
     return Owned(From);
   }
 
   if (!isIntegralOrEnumerationType(From->getType(), AllowScopedEnumerations) &&
-      NotIntDiag.getDiagID())
-    Diag(Loc, NotIntDiag) << From->getType() << From->getSourceRange();
+      !Diagnoser.Suppress) {
+    Diagnoser.diagnoseNotInt(*this, Loc, From->getType())
+      << From->getSourceRange();
+  }
 
   return DefaultLvalueConversion(From);
 }

lib/Sema/SemaStmt.cpp

@@ -521,16 +521,56 @@ Sema::ActOnStartOfSwitchStmt(SourceLocation SwitchLoc, Expr *Cond,
   if (!Cond)
     return StmtError();
 
+  class SwitchConvertDiagnoser : public ICEConvertDiagnoser {
+    Expr *Cond;
+    
+  public:
+    SwitchConvertDiagnoser(Expr *Cond)
+      : ICEConvertDiagnoser(false, true), Cond(Cond) { }
+    
+    virtual DiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
+                                             QualType T) {
+      return S.Diag(Loc, diag::err_typecheck_statement_requires_integer) << T;
+    }
+    
+    virtual DiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
+                                                 QualType T) {
+      return S.Diag(Loc, diag::err_switch_incomplete_class_type)
+               << T << Cond->getSourceRange();
+    }
+    
+    virtual DiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
+                                                   QualType T,
+                                                   QualType ConvTy) {
+      return S.Diag(Loc, diag::err_switch_explicit_conversion) << T << ConvTy;
+    }
+    
+    virtual DiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
+                                               QualType ConvTy) {
+      return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
+        << ConvTy->isEnumeralType() << ConvTy;
+    }
+    
+    virtual DiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
+                                                QualType T) {
+      return S.Diag(Loc, diag::err_switch_multiple_conversions) << T;
+    }
+    
+    virtual DiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
+                                            QualType ConvTy) {
+      return S.Diag(Conv->getLocation(), diag::note_switch_conversion)
+      << ConvTy->isEnumeralType() << ConvTy;
+    }
+    
+    virtual DiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
+                                                 QualType T,
+                                                 QualType ConvTy) {
+      return DiagnosticBuilder::getEmpty();
+    }
+  } SwitchDiagnoser(Cond);
+
   CondResult
-    = ConvertToIntegralOrEnumerationType(SwitchLoc, Cond,
-                          PDiag(diag::err_typecheck_statement_requires_integer),
-                                   PDiag(diag::err_switch_incomplete_class_type)
-                                     << Cond->getSourceRange(),
-                                   PDiag(diag::err_switch_explicit_conversion),
-                                         PDiag(diag::note_switch_conversion),
-                                   PDiag(diag::err_switch_multiple_conversions),
-                                         PDiag(diag::note_switch_conversion),
-                                         PDiag(0),
+    = ConvertToIntegralOrEnumerationType(SwitchLoc, Cond, SwitchDiagnoser,
                                          /*AllowScopedEnumerations*/ true);
   if (CondResult.isInvalid()) return StmtError();
   Cond = CondResult.take();

lib/Sema/SemaTemplate.cpp

@@ -4113,8 +4113,20 @@ ExprResult Sema::CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
       Diag(Param->getLocation(), diag::note_template_param_here);
       return ExprError();
     } else if (!Arg->isValueDependent()) {
-      Arg = VerifyIntegerConstantExpression(Arg, &Value,
-        PDiag(diag::err_template_arg_not_ice) << ArgType, false).take();
+      class TmplArgICEDiagnoser : public VerifyICEDiagnoser {
+        QualType T;
+        
+      public:
+        TmplArgICEDiagnoser(QualType T) : T(T) { }
+        
+        virtual void diagnoseNotICE(Sema &S, SourceLocation Loc,
+                                    SourceRange SR) {
+          S.Diag(Loc, diag::err_template_arg_not_ice) << T << SR;
+        }
+      } Diagnoser(ArgType);
+
+      Arg = VerifyIntegerConstantExpression(Arg, &Value, Diagnoser,
+                                            false).take();
       if (!Arg)
         return ExprError();
     }

lib/Sema/SemaTemplateInstantiateDecl.cpp

@@ -2354,9 +2354,10 @@ static void InstantiateExceptionSpec(Sema &SemaRef, FunctionDecl *New,
       NoexceptExpr = E.take();
       if (!NoexceptExpr->isTypeDependent() &&
           !NoexceptExpr->isValueDependent())
-        NoexceptExpr = SemaRef.VerifyIntegerConstantExpression(NoexceptExpr,
-          0, SemaRef.PDiag(diag::err_noexcept_needs_constant_expression),
-          /*AllowFold*/ false).take();
+        NoexceptExpr
+          = SemaRef.VerifyIntegerConstantExpression(NoexceptExpr,
+              0, diag::err_noexcept_needs_constant_expression,
+              /*AllowFold*/ false).take();
     }
   }
 

lib/Sema/SemaType.cpp

@@ -1205,9 +1205,20 @@ QualType Sema::BuildReferenceType(QualType T, bool SpelledAsLValue,
 static bool isArraySizeVLA(Sema &S, Expr *ArraySize, llvm::APSInt &SizeVal) {
   // If the size is an ICE, it certainly isn't a VLA. If we're in a GNU mode
   // (like gnu99, but not c99) accept any evaluatable value as an extension.
-  return S.VerifyIntegerConstantExpression(
-      ArraySize, &SizeVal, S.PDiag(), S.LangOpts.GNUMode,
-      S.PDiag(diag::ext_vla_folded_to_constant)).isInvalid();
+  class VLADiagnoser : public Sema::VerifyICEDiagnoser {
+  public:
+    VLADiagnoser() : Sema::VerifyICEDiagnoser(true) {}
+    
+    virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
+    }
+    
+    virtual void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR) {
+      S.Diag(Loc, diag::ext_vla_folded_to_constant) << SR;
+    }
+  } Diagnoser;
+  
+  return S.VerifyIntegerConstantExpression(ArraySize, &SizeVal, Diagnoser,
+                                           S.LangOpts.GNUMode).isInvalid();
 }