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diff --git a/contrib/llvm/tools/clang/lib/Sema/SemaExceptionSpec.cpp b/contrib/llvm/tools/clang/lib/Sema/SemaExceptionSpec.cpp
new file mode 100644
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+++ b/contrib/llvm/tools/clang/lib/Sema/SemaExceptionSpec.cpp
@@ -0,0 +1,506 @@
+//===--- SemaExceptionSpec.cpp - C++ Exception Specifications ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides Sema routines for C++ exception specification testing.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Sema.h"
+#include "clang/AST/CXXInheritance.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/TypeLoc.h"
+#include "clang/Lex/Preprocessor.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/SourceManager.h"
+#include "llvm/ADT/SmallPtrSet.h"
+
+namespace clang {
+
+static const FunctionProtoType *GetUnderlyingFunction(QualType T)
+{
+  if (const PointerType *PtrTy = T->getAs<PointerType>())
+    T = PtrTy->getPointeeType();
+  else if (const ReferenceType *RefTy = T->getAs<ReferenceType>())
+    T = RefTy->getPointeeType();
+  else if (const MemberPointerType *MPTy = T->getAs<MemberPointerType>())
+    T = MPTy->getPointeeType();
+  return T->getAs<FunctionProtoType>();
+}
+
+/// CheckSpecifiedExceptionType - Check if the given type is valid in an
+/// exception specification. Incomplete types, or pointers to incomplete types
+/// other than void are not allowed.
+bool Sema::CheckSpecifiedExceptionType(QualType T, const SourceRange &Range) {
+
+  // This check (and the similar one below) deals with issue 437, that changes
+  // C++ 9.2p2 this way:
+  // Within the class member-specification, the class is regarded as complete
+  // within function bodies, default arguments, exception-specifications, and
+  // constructor ctor-initializers (including such things in nested classes).
+  if (T->isRecordType() && T->getAs<RecordType>()->isBeingDefined())
+    return false;
+    
+  // C++ 15.4p2: A type denoted in an exception-specification shall not denote
+  //   an incomplete type.
+  if (RequireCompleteType(Range.getBegin(), T,
+      PDiag(diag::err_incomplete_in_exception_spec) << /*direct*/0 << Range))
+    return true;
+
+  // C++ 15.4p2: A type denoted in an exception-specification shall not denote
+  //   an incomplete type a pointer or reference to an incomplete type, other
+  //   than (cv) void*.
+  int kind;
+  if (const PointerType* IT = T->getAs<PointerType>()) {
+    T = IT->getPointeeType();
+    kind = 1;
+  } else if (const ReferenceType* IT = T->getAs<ReferenceType>()) {
+    T = IT->getPointeeType();
+    kind = 2;
+  } else
+    return false;
+
+  // Again as before
+  if (T->isRecordType() && T->getAs<RecordType>()->isBeingDefined())
+    return false;
+    
+  if (!T->isVoidType() && RequireCompleteType(Range.getBegin(), T,
+      PDiag(diag::err_incomplete_in_exception_spec) << kind << Range))
+    return true;
+
+  return false;
+}
+
+/// CheckDistantExceptionSpec - Check if the given type is a pointer or pointer
+/// to member to a function with an exception specification. This means that
+/// it is invalid to add another level of indirection.
+bool Sema::CheckDistantExceptionSpec(QualType T) {
+  if (const PointerType *PT = T->getAs<PointerType>())
+    T = PT->getPointeeType();
+  else if (const MemberPointerType *PT = T->getAs<MemberPointerType>())
+    T = PT->getPointeeType();
+  else
+    return false;
+
+  const FunctionProtoType *FnT = T->getAs<FunctionProtoType>();
+  if (!FnT)
+    return false;
+
+  return FnT->hasExceptionSpec();
+}
+
+bool Sema::CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New) {
+  bool MissingExceptionSpecification = false;
+  bool MissingEmptyExceptionSpecification = false;
+  if (!CheckEquivalentExceptionSpec(PDiag(diag::err_mismatched_exception_spec),
+                                    PDiag(diag::note_previous_declaration),
+                                    Old->getType()->getAs<FunctionProtoType>(),
+                                    Old->getLocation(),
+                                    New->getType()->getAs<FunctionProtoType>(),
+                                    New->getLocation(),
+                                    &MissingExceptionSpecification,
+                                    &MissingEmptyExceptionSpecification))
+    return false;
+
+  // The failure was something other than an empty exception
+  // specification; return an error.
+  if (!MissingExceptionSpecification && !MissingEmptyExceptionSpecification)
+    return true;
+
+  // The new function declaration is only missing an empty exception
+  // specification "throw()". If the throw() specification came from a
+  // function in a system header that has C linkage, just add an empty
+  // exception specification to the "new" declaration. This is an
+  // egregious workaround for glibc, which adds throw() specifications
+  // to many libc functions as an optimization. Unfortunately, that
+  // optimization isn't permitted by the C++ standard, so we're forced
+  // to work around it here.
+  if (MissingEmptyExceptionSpecification &&
+      isa<FunctionProtoType>(New->getType()) &&
+      (Old->getLocation().isInvalid() ||
+       Context.getSourceManager().isInSystemHeader(Old->getLocation())) &&
+      Old->isExternC()) {
+    const FunctionProtoType *NewProto 
+      = cast<FunctionProtoType>(New->getType());
+    QualType NewType = Context.getFunctionType(NewProto->getResultType(),
+                                               NewProto->arg_type_begin(),
+                                               NewProto->getNumArgs(),
+                                               NewProto->isVariadic(),
+                                               NewProto->getTypeQuals(),
+                                               true, false, 0, 0,
+                                               NewProto->getExtInfo());
+    New->setType(NewType);
+    return false;
+  }
+
+  if (MissingExceptionSpecification && isa<FunctionProtoType>(New->getType())) {
+    const FunctionProtoType *NewProto 
+      = cast<FunctionProtoType>(New->getType());
+    const FunctionProtoType *OldProto
+      = Old->getType()->getAs<FunctionProtoType>();
+
+    // Update the type of the function with the appropriate exception
+    // specification.
+    QualType NewType = Context.getFunctionType(NewProto->getResultType(),
+                                               NewProto->arg_type_begin(),
+                                               NewProto->getNumArgs(),
+                                               NewProto->isVariadic(),
+                                               NewProto->getTypeQuals(),
+                                               OldProto->hasExceptionSpec(),
+                                               OldProto->hasAnyExceptionSpec(),
+                                               OldProto->getNumExceptions(),
+                                               OldProto->exception_begin(),
+                                               NewProto->getExtInfo());
+    New->setType(NewType);
+
+    // If exceptions are disabled, suppress the warning about missing
+    // exception specifications for new and delete operators.
+    if (!getLangOptions().Exceptions) {
+      switch (New->getDeclName().getCXXOverloadedOperator()) {
+      case OO_New:
+      case OO_Array_New:
+      case OO_Delete:
+      case OO_Array_Delete:
+        if (New->getDeclContext()->isTranslationUnit())
+          return false;
+        break;
+
+      default:
+        break;
+      }
+    } 
+
+    // Warn about the lack of exception specification.
+    llvm::SmallString<128> ExceptionSpecString;
+    llvm::raw_svector_ostream OS(ExceptionSpecString);
+    OS << "throw(";
+    bool OnFirstException = true;
+    for (FunctionProtoType::exception_iterator E = OldProto->exception_begin(),
+                                            EEnd = OldProto->exception_end();
+         E != EEnd;
+         ++E) {
+      if (OnFirstException)
+        OnFirstException = false;
+      else
+        OS << ", ";
+      
+      OS << E->getAsString(Context.PrintingPolicy);
+    }
+    OS << ")";
+    OS.flush();
+
+    SourceLocation AfterParenLoc;
+    if (TypeSourceInfo *TSInfo = New->getTypeSourceInfo()) {
+      TypeLoc TL = TSInfo->getTypeLoc();
+      if (const FunctionTypeLoc *FTLoc = dyn_cast<FunctionTypeLoc>(&TL))
+        AfterParenLoc = PP.getLocForEndOfToken(FTLoc->getRParenLoc());
+    }
+
+    if (AfterParenLoc.isInvalid())
+      Diag(New->getLocation(), diag::warn_missing_exception_specification)
+        << New << OS.str();
+    else {
+      // FIXME: This will get more complicated with C++0x
+      // late-specified return types.
+      Diag(New->getLocation(), diag::warn_missing_exception_specification)
+        << New << OS.str()
+        << FixItHint::CreateInsertion(AfterParenLoc, " " + OS.str().str());
+    }
+
+    if (!Old->getLocation().isInvalid())
+      Diag(Old->getLocation(), diag::note_previous_declaration);
+
+    return false;    
+  }
+
+  Diag(New->getLocation(), diag::err_mismatched_exception_spec);
+  Diag(Old->getLocation(), diag::note_previous_declaration);
+  return true;
+}
+
+/// CheckEquivalentExceptionSpec - Check if the two types have equivalent
+/// exception specifications. Exception specifications are equivalent if
+/// they allow exactly the same set of exception types. It does not matter how
+/// that is achieved. See C++ [except.spec]p2.
+bool Sema::CheckEquivalentExceptionSpec(
+    const FunctionProtoType *Old, SourceLocation OldLoc,
+    const FunctionProtoType *New, SourceLocation NewLoc) {
+  return CheckEquivalentExceptionSpec(
+                                    PDiag(diag::err_mismatched_exception_spec),
+                                      PDiag(diag::note_previous_declaration),
+                                      Old, OldLoc, New, NewLoc);
+}
+
+/// CheckEquivalentExceptionSpec - Check if the two types have equivalent
+/// exception specifications. Exception specifications are equivalent if
+/// they allow exactly the same set of exception types. It does not matter how
+/// that is achieved. See C++ [except.spec]p2.
+bool Sema::CheckEquivalentExceptionSpec(const PartialDiagnostic &DiagID, 
+                                        const PartialDiagnostic & NoteID,
+                                        const FunctionProtoType *Old, 
+                                        SourceLocation OldLoc,
+                                        const FunctionProtoType *New, 
+                                        SourceLocation NewLoc,
+                                        bool *MissingExceptionSpecification,
+                                     bool *MissingEmptyExceptionSpecification)  {
+  if (MissingExceptionSpecification)
+    *MissingExceptionSpecification = false;
+
+  if (MissingEmptyExceptionSpecification)
+    *MissingEmptyExceptionSpecification = false;
+
+  bool OldAny = !Old->hasExceptionSpec() || Old->hasAnyExceptionSpec();
+  bool NewAny = !New->hasExceptionSpec() || New->hasAnyExceptionSpec();
+  if (OldAny && NewAny)
+    return false;
+  if (OldAny || NewAny) {
+    if (MissingExceptionSpecification && Old->hasExceptionSpec() &&
+        !New->hasExceptionSpec()) {
+      // The old type has an exception specification of some sort, but
+      // the new type does not.
+      *MissingExceptionSpecification = true;
+
+      if (MissingEmptyExceptionSpecification && 
+          !Old->hasAnyExceptionSpec() && Old->getNumExceptions() == 0) {
+        // The old type has a throw() exception specification and the
+        // new type has no exception specification, and the caller asked
+        // to handle this itself.
+        *MissingEmptyExceptionSpecification = true;
+      }
+
+      return true;
+    }
+
+    Diag(NewLoc, DiagID);
+    if (NoteID.getDiagID() != 0)
+      Diag(OldLoc, NoteID);
+    return true;
+  }
+
+  bool Success = true;
+  // Both have a definite exception spec. Collect the first set, then compare
+  // to the second.
+  llvm::SmallPtrSet<CanQualType, 8> OldTypes, NewTypes;
+  for (FunctionProtoType::exception_iterator I = Old->exception_begin(),
+       E = Old->exception_end(); I != E; ++I)
+    OldTypes.insert(Context.getCanonicalType(*I).getUnqualifiedType());
+
+  for (FunctionProtoType::exception_iterator I = New->exception_begin(),
+       E = New->exception_end(); I != E && Success; ++I) {
+    CanQualType TypePtr = Context.getCanonicalType(*I).getUnqualifiedType();
+    if(OldTypes.count(TypePtr))
+      NewTypes.insert(TypePtr);
+    else
+      Success = false;
+  }
+
+  Success = Success && OldTypes.size() == NewTypes.size();
+
+  if (Success) {
+    return false;
+  }
+  Diag(NewLoc, DiagID);
+  if (NoteID.getDiagID() != 0)
+    Diag(OldLoc, NoteID);
+  return true;
+}
+
+/// CheckExceptionSpecSubset - Check whether the second function type's
+/// exception specification is a subset (or equivalent) of the first function
+/// type. This is used by override and pointer assignment checks.
+bool Sema::CheckExceptionSpecSubset(
+    const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
+    const FunctionProtoType *Superset, SourceLocation SuperLoc,
+    const FunctionProtoType *Subset, SourceLocation SubLoc) {
+  // FIXME: As usual, we could be more specific in our error messages, but
+  // that better waits until we've got types with source locations.
+
+  if (!SubLoc.isValid())
+    SubLoc = SuperLoc;
+
+  // If superset contains everything, we're done.
+  if (!Superset->hasExceptionSpec() || Superset->hasAnyExceptionSpec())
+    return CheckParamExceptionSpec(NoteID, Superset, SuperLoc, Subset, SubLoc);
+
+  // It does not. If the subset contains everything, we've failed.
+  if (!Subset->hasExceptionSpec() || Subset->hasAnyExceptionSpec()) {
+    Diag(SubLoc, DiagID);
+    if (NoteID.getDiagID() != 0)
+      Diag(SuperLoc, NoteID);
+    return true;
+  }
+
+  // Neither contains everything. Do a proper comparison.
+  for (FunctionProtoType::exception_iterator SubI = Subset->exception_begin(),
+       SubE = Subset->exception_end(); SubI != SubE; ++SubI) {
+    // Take one type from the subset.
+    QualType CanonicalSubT = Context.getCanonicalType(*SubI);
+    // Unwrap pointers and references so that we can do checks within a class
+    // hierarchy. Don't unwrap member pointers; they don't have hierarchy
+    // conversions on the pointee.
+    bool SubIsPointer = false;
+    if (const ReferenceType *RefTy = CanonicalSubT->getAs<ReferenceType>())
+      CanonicalSubT = RefTy->getPointeeType();
+    if (const PointerType *PtrTy = CanonicalSubT->getAs<PointerType>()) {
+      CanonicalSubT = PtrTy->getPointeeType();
+      SubIsPointer = true;
+    }
+    bool SubIsClass = CanonicalSubT->isRecordType();
+    CanonicalSubT = CanonicalSubT.getLocalUnqualifiedType();
+
+    CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
+                       /*DetectVirtual=*/false);
+
+    bool Contained = false;
+    // Make sure it's in the superset.
+    for (FunctionProtoType::exception_iterator SuperI =
+           Superset->exception_begin(), SuperE = Superset->exception_end();
+         SuperI != SuperE; ++SuperI) {
+      QualType CanonicalSuperT = Context.getCanonicalType(*SuperI);
+      // SubT must be SuperT or derived from it, or pointer or reference to
+      // such types.
+      if (const ReferenceType *RefTy = CanonicalSuperT->getAs<ReferenceType>())
+        CanonicalSuperT = RefTy->getPointeeType();
+      if (SubIsPointer) {
+        if (const PointerType *PtrTy = CanonicalSuperT->getAs<PointerType>())
+          CanonicalSuperT = PtrTy->getPointeeType();
+        else {
+          continue;
+        }
+      }
+      CanonicalSuperT = CanonicalSuperT.getLocalUnqualifiedType();
+      // If the types are the same, move on to the next type in the subset.
+      if (CanonicalSubT == CanonicalSuperT) {
+        Contained = true;
+        break;
+      }
+
+      // Otherwise we need to check the inheritance.
+      if (!SubIsClass || !CanonicalSuperT->isRecordType())
+        continue;
+
+      Paths.clear();
+      if (!IsDerivedFrom(CanonicalSubT, CanonicalSuperT, Paths))
+        continue;
+
+      if (Paths.isAmbiguous(Context.getCanonicalType(CanonicalSuperT)))
+        continue;
+
+      // Do this check from a context without privileges.
+      switch (CheckBaseClassAccess(SourceLocation(),
+                                   CanonicalSuperT, CanonicalSubT,
+                                   Paths.front(),
+                                   /*Diagnostic*/ 0,
+                                   /*ForceCheck*/ true,
+                                   /*ForceUnprivileged*/ true)) {
+      case AR_accessible: break;
+      case AR_inaccessible: continue;
+      case AR_dependent:
+        llvm_unreachable("access check dependent for unprivileged context");
+        break;
+      case AR_delayed:
+        llvm_unreachable("access check delayed in non-declaration");
+        break;
+      }
+
+      Contained = true;
+      break;
+    }
+    if (!Contained) {
+      Diag(SubLoc, DiagID);
+      if (NoteID.getDiagID() != 0)
+        Diag(SuperLoc, NoteID);
+      return true;
+    }
+  }
+  // We've run half the gauntlet.
+  return CheckParamExceptionSpec(NoteID, Superset, SuperLoc, Subset, SubLoc);
+}
+
+static bool CheckSpecForTypesEquivalent(Sema &S,
+    const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
+    QualType Target, SourceLocation TargetLoc,
+    QualType Source, SourceLocation SourceLoc)
+{
+  const FunctionProtoType *TFunc = GetUnderlyingFunction(Target);
+  if (!TFunc)
+    return false;
+  const FunctionProtoType *SFunc = GetUnderlyingFunction(Source);
+  if (!SFunc)
+    return false;
+
+  return S.CheckEquivalentExceptionSpec(DiagID, NoteID, TFunc, TargetLoc,
+                                        SFunc, SourceLoc);
+}
+
+/// CheckParamExceptionSpec - Check if the parameter and return types of the
+/// two functions have equivalent exception specs. This is part of the
+/// assignment and override compatibility check. We do not check the parameters
+/// of parameter function pointers recursively, as no sane programmer would
+/// even be able to write such a function type.
+bool Sema::CheckParamExceptionSpec(const PartialDiagnostic & NoteID,
+    const FunctionProtoType *Target, SourceLocation TargetLoc,
+    const FunctionProtoType *Source, SourceLocation SourceLoc)
+{
+  if (CheckSpecForTypesEquivalent(*this,
+                           PDiag(diag::err_deep_exception_specs_differ) << 0, 
+                                  PDiag(),
+                                  Target->getResultType(), TargetLoc,
+                                  Source->getResultType(), SourceLoc))
+    return true;
+
+  // We shouldn't even be testing this unless the arguments are otherwise
+  // compatible.
+  assert(Target->getNumArgs() == Source->getNumArgs() &&
+         "Functions have different argument counts.");
+  for (unsigned i = 0, E = Target->getNumArgs(); i != E; ++i) {
+    if (CheckSpecForTypesEquivalent(*this,
+                           PDiag(diag::err_deep_exception_specs_differ) << 1, 
+                                    PDiag(),
+                                    Target->getArgType(i), TargetLoc,
+                                    Source->getArgType(i), SourceLoc))
+      return true;
+  }
+  return false;
+}
+
+bool Sema::CheckExceptionSpecCompatibility(Expr *From, QualType ToType)
+{
+  // First we check for applicability.
+  // Target type must be a function, function pointer or function reference.
+  const FunctionProtoType *ToFunc = GetUnderlyingFunction(ToType);
+  if (!ToFunc)
+    return false;
+
+  // SourceType must be a function or function pointer.
+  const FunctionProtoType *FromFunc = GetUnderlyingFunction(From->getType());
+  if (!FromFunc)
+    return false;
+
+  // Now we've got the correct types on both sides, check their compatibility.
+  // This means that the source of the conversion can only throw a subset of
+  // the exceptions of the target, and any exception specs on arguments or
+  // return types must be equivalent.
+  return CheckExceptionSpecSubset(PDiag(diag::err_incompatible_exception_specs),
+                                  PDiag(), ToFunc, 
+                                  From->getSourceRange().getBegin(),
+                                  FromFunc, SourceLocation());
+}
+
+bool Sema::CheckOverridingFunctionExceptionSpec(const CXXMethodDecl *New,
+                                                const CXXMethodDecl *Old) {
+  return CheckExceptionSpecSubset(PDiag(diag::err_override_exception_spec),
+                                  PDiag(diag::note_overridden_virtual_function),
+                                  Old->getType()->getAs<FunctionProtoType>(),
+                                  Old->getLocation(),
+                                  New->getType()->getAs<FunctionProtoType>(),
+                                  New->getLocation());
+}
+
+} // end namespace clang