[MSVC] PR27132: Proper mangling for __unaligned qualifier

[andreybokhanko]

Summary

This patch implements proper mangling for MS-specific "unaligned" qualifier. The mangling part itself is tiny; most of the patch is required to convert "unaligned" from an ignored qualifier to a non-ignored one.

See PR27132 for an example of code that mangles incorrectly at the moment.

Yours,

Andrey

Software Engineer
Intel Compiler Team

[aaron.ballman]

I'd like to see some Sema tests for sanity checking; like applying __unaligned to a non-pointer type, to a declaration, when -fno-ms-extensions is enabled, etc.

include/clang/Basic/Attr.td

2080 ↗

(On Diff #52055)

This is possibly missing let LangOpts = [MicrosoftExt];

include/clang/Basic/AttrDocs.td

1964 ↗

(On Diff #52055)

"an" unaligned address.

lib/Sema/SemaType.cpp

5555 ↗

(On Diff #52055)

This appears to be untested, but really should have a test case to ensure we don't regress later.

[rnk]

include/clang/Basic/AttrDocs.td

1970 ↗

(On Diff #52055)

I don't think "IPF targets" will be understood by readers to mean "Itanium targets". I'd just drop everything before the semicolon. At some point, we might want to add support __unaligned __m128*. Today we'll copy that with movaps.

lib/Sema/SemaType.cpp

5555 ↗

(On Diff #52055)

+1, although I recall that someone else from Intel wanted to make sure this test case works:

struct A { void g() __unaligned {} };

I could take it or leave it. I don't think that rejecting this program will break very much real code.

[majnemer]

I didn't implement a mangling for __unaligned because our implementation of it is broken.
It should not be modeled as an attribute, it should be modeled as a qualifier because it is possible to overload on it.

[andreybokhanko]

Resolved [some of] comments made by Aaron and Reid.

[andreybokhanko]

Aaron, Reid, David, thank you for the review!

I resolved some of your comments. As for

In D18596#386841, @aaron.ballman wrote:

I'd like to see some Sema tests for sanity checking; like applying __unaligned to a non-pointer type, to a declaration, when -fno-ms-extensions is enabled, etc.

Do we want to accept unaligned for non-pointer types, as MS compiler does? Their doc (https://msdn.microsoft.com/en-us/library/ms177389.aspx) only mentions pointers, but cl.exe also accepts non-pointers with unaligned, with no visible effect to generated code (including mangling). Clang currently does accept this, so starting to issue an error would be a regression.

In D18596#387129, @majnemer wrote:

I didn't implement a mangling for __unaligned because our implementation of it is broken.
It should not be modeled as an attribute, it should be modeled as a qualifier because it is possible to overload on it.

I see.

Well, now we have not quite compatible implementation + incorrect mangling. My patch fixes mangling part. IMHO, implementation part should be fixed in a separate patch.

Andrey

[aaron.ballman]

In D18596#388148, @andreybokhanko wrote:

Aaron, Reid, David, thank you for the review!

I resolved some of your comments. As for

In D18596#386841, @aaron.ballman wrote:

I'd like to see some Sema tests for sanity checking; like applying __unaligned to a non-pointer type, to a declaration, when -fno-ms-extensions is enabled, etc.

Do we want to accept unaligned for non-pointer types, as MS compiler does? Their doc (https://msdn.microsoft.com/en-us/library/ms177389.aspx) only mentions pointers, but cl.exe also accepts non-pointers with unaligned, with no visible effect to generated code (including mangling). Clang currently does accept this, so starting to issue an error would be a regression.

Regression is a bit of a question mark, to me depending on the diagnostic. I think warning the user "this has absolutely no effect" is a reasonable diagnostic for that situation -- the user wrote something, possibly expecting it to have an effect, and it turns out that it does absolutely nothing (including in the compiler that implements the language extension). If MSVC were to ever add semantic effect in those cases (diverging from what Clang implements), the diagnostic becomes even more important for Clang users. So I think it's fine to accept __unaligned for non-pointer types, but issue an "attribute ignored" warning diagnostic.

[andreybokhanko]

Added Sema test, as per Aaron's and Reid's request.

[andreybokhanko]

In D18596#388295, @aaron.ballman wrote:

Regression is a bit of a question mark, to me depending on the diagnostic. I think warning the user "this has absolutely no effect" is a reasonable diagnostic for that situation -- the user wrote something, possibly expecting it to have an effect, and it turns out that it does absolutely nothing (including in the compiler that implements the language extension). If MSVC were to ever add semantic effect in those cases (diverging from what Clang implements), the diagnostic becomes even more important for Clang users. So I think it's fine to accept __unaligned for non-pointer types, but issue an "attribute ignored" warning diagnostic.

As David wrote, __unaligned is a qualifier in MSVC, so MS accepts the following:

__unaligned int *p;

as a correct usage (and does mangling for __unaligned).

We model it as an attribute, so we create a new AttributedType for int, not for the pointer. This is OK, since our mangling code takes PointeeType and checks presence of the attribute. Unfortunately, this means that we can't issue warnings, as it's impossible (to the best of my knowledge) to distinguish between

unaligned int *p;
unaligned int p;

in processTypeAttrs function.

As I said before, the purpose of this patch is to implement correct mangling (and thus, improve object level compatibility with MSVC), not to provide a fully correct implementation of __unaligned.

Another alternative is to model __unaligned as a qualifier, but this would require addition of an extra field to TypeBitfields. Do we want to do this for an ignored qualifier? I don't see any practical purpose.

Andrey

[majnemer]

In D18596#392098, @andreybokhanko wrote:

In D18596#388295, @aaron.ballman wrote:

Regression is a bit of a question mark, to me depending on the diagnostic. I think warning the user "this has absolutely no effect" is a reasonable diagnostic for that situation -- the user wrote something, possibly expecting it to have an effect, and it turns out that it does absolutely nothing (including in the compiler that implements the language extension). If MSVC were to ever add semantic effect in those cases (diverging from what Clang implements), the diagnostic becomes even more important for Clang users. So I think it's fine to accept __unaligned for non-pointer types, but issue an "attribute ignored" warning diagnostic.

As David wrote, __unaligned is a qualifier in MSVC, so MS accepts the following:

__unaligned int *p;

as a correct usage (and does mangling for __unaligned).

We model it as an attribute, so we create a new AttributedType for int, not for the pointer. This is OK, since our mangling code takes PointeeType and checks presence of the attribute. Unfortunately, this means that we can't issue warnings, as it's impossible (to the best of my knowledge) to distinguish between

unaligned int *p;
unaligned int p;

in processTypeAttrs function.

As I said before, the purpose of this patch is to implement correct mangling (and thus, improve object level compatibility with MSVC), not to provide a fully correct implementation of __unaligned.

Another alternative is to model __unaligned as a qualifier, but this would require addition of an extra field to TypeBitfields.

That's OK. We have plenty of bits in the "address_space" field to steal from.

Do we want to do this for an ignored qualifier? I don't see any practical purpose.

It's not ignored for Windows on ARM.

Andrey

[andreybokhanko]

In D18596#392341, @majnemer wrote:

In D18596#392098, @andreybokhanko wrote:

Do we want to do this for an ignored qualifier? I don't see any practical purpose.

It's not ignored for Windows on ARM.

Hmmm... MS documentation explicitly mentions IPF only:

When you declare a pointer with the __unaligned modifier, the compiler assumes that the pointer addresses data that is not aligned. Consequently, for an application that targets an Itanium Processor Family (IPF) computer, the compiler generates code that reads the unaligned data one byte at a time.

OK, I will implement _unaligned as a qualifier, if you think this is the right way to go. Note, though, that it will remain ignored, as there is no support for _unaligned in LLVM IR.

Andrey

[andreybokhanko]

This patch implements "__unaligned" as a qualifier (as per David Majnemer's request).

Most of the changes are miscellaneous small stuff one has to add when adding a new qualifier.

Other notable things are:

• One bit is stolen from "AddressSpace" to store __unaligned. This resulted in changes in OpenCL code and tests, that implicitly assumed that AddressSpace size is 24 bits.
• Sema checks added. It verifies that __unaligned can be used with non-pointers, for overloading and that it doesn't get recognized without -fms-compatibility option.
• Proper mangling (along with tests) for unaligned added. Note that non-pointer unaligned args don't affect mangling.

Andrey

[rnk]

test/SemaCXX/MicrosoftExtensions.cpp

89 ↗

(On Diff #53022)

Surely we can come up with some tougher overloading test cases. I noticed MSVC generates a warning when converting from '__unaligned T*' to 'T*' with this code:

extern "C" int puts(const char *);
void f(__unaligned int *p) {
  puts("unaligned");
}
void f(int *p) {
  puts("aligned");
}
void g(int *p) {
  puts("g");
}
int main() {
  int *p = 0;
  __unaligned int *q = 0;
  f(p);
  f(q);
  g(p);
  g(q); // C4090
}

[andreybokhanko]

1. Added more comprehensive overloading tests
2. Added a warning (in C mode) / error (in C++ mode) on unaligned to non-unaligned type conversion

Andrey

[andreybokhanko]

test/SemaCXX/MicrosoftExtensions.cpp

89 ↗

(On Diff #53509)

Reid, thanks for looking into this patch!

I added more comprehensive overloading tests.

As for printing a warning, I added it -- in C mode. In C++ mode we don't allow types conversion that loses qualifiers. I do the same for __unaligned. If you want me to implement printing a warning in C++ mode as well (as MS compiler does), I would appreciate any hints on where the best place to do it. Putting it directly into code that verifies qualifiers compatibility seems to be odd.

Andrey

[rnk]

Thanks! This looks great.

test/SemaCXX/MicrosoftExtensions.cpp

89 ↗

(On Diff #53509)

I think we can keep it as you have it for now. We can wait and see if users complain about the C++ mode error.

[andreybokhanko]

Reid, thank you!

Yours,
Andrey

cfe/trunk/include/clang/AST/Type.h

enum ObjCLifetime {
     OCL_Weak,
 
     /// Assigning into this object requires a lifetime extension.
     OCL_Autoreleasing
   };
 
   enum {
     /// The maximum supported address space number.
-    /// 24 bits should be enough for anyone.
-    MaxAddressSpace = 0xffffffu,
+    /// 23 bits should be enough for anyone.
+    MaxAddressSpace = 0x7fffffu,
 
     /// The width of the "fast" qualifier mask.
     FastWidth = 3,
 
     /// The fast qualifier mask.
     FastMask = (1 << FastWidth) - 1
   };
 
public:
   void removeCVRQualifiers() {
     removeCVRQualifiers(CVRMask);
   }
   void addCVRQualifiers(unsigned mask) {
     assert(!(mask & ~CVRMask) && "bitmask contains non-CVR bits");
     Mask |= mask;
   }
 
+  bool hasUnaligned() const { return Mask & UMask; }
+  void setUnaligned(bool flag) {
+    Mask = (Mask & ~UMask) | (flag ? UMask : 0);
+  }
+  void removeUnaligned() { Mask &= ~UMask; }
+  void addUnaligned() { Mask |= UMask; }
+
   bool hasObjCGCAttr() const { return Mask & GCAttrMask; }
   GC getObjCGCAttr() const { return GC((Mask & GCAttrMask) >> GCAttrShift); }
   void setObjCGCAttr(GC type) {
     Mask = (Mask & ~GCAttrMask) | (type << GCAttrShift);
   }
   void removeObjCGCAttr() { setObjCGCAttr(GCNone); }
   void addObjCGCAttr(GC type) {
     assert(type);
bool compatiblyIncludes(Qualifiers other) const {
     return isAddressSpaceSupersetOf(other) &&
            // ObjC GC qualifiers can match, be added, or be removed, but can't
            // be changed.
            (getObjCGCAttr() == other.getObjCGCAttr() || !hasObjCGCAttr() ||
             !other.hasObjCGCAttr()) &&
            // ObjC lifetime qualifiers must match exactly.
            getObjCLifetime() == other.getObjCLifetime() &&
            // CVR qualifiers may subset.
-           (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask));
+           (((Mask & CVRMask) | (other.Mask & CVRMask)) == (Mask & CVRMask)) &&
+           // U qualifier may superset.
+           (!(other.Mask & UMask) || (Mask & UMask));
   }
 
   /// \brief Determines if these qualifiers compatibly include another set of
   /// qualifiers from the narrow perspective of Objective-C ARC lifetime.
   ///
   /// One set of Objective-C lifetime qualifiers compatibly includes the other
   /// if the lifetime qualifiers match, or if both are non-__weak and the
   /// including set also contains the 'const' qualifier, or both are non-__weak
void print(raw_ostream &OS, const PrintingPolicy &Policy,
              bool appendSpaceIfNonEmpty = false) const;
 
   void Profile(llvm::FoldingSetNodeID &ID) const {
     ID.AddInteger(Mask);
   }
 
 private:
 
-  // bits:     |0 1 2|3 .. 4|5  ..  7|8   ...   31|
-  //           |C R V|GCAttr|Lifetime|AddressSpace|
+  // bits:     |0 1 2|3|4 .. 5|6  ..  8|9   ...   31|
+  //           |C R V|U|GCAttr|Lifetime|AddressSpace|
   uint32_t Mask;
 
-  static const uint32_t GCAttrMask = 0x18;
-  static const uint32_t GCAttrShift = 3;
-  static const uint32_t LifetimeMask = 0xE0;
-  static const uint32_t LifetimeShift = 5;
-  static const uint32_t AddressSpaceMask = ~(CVRMask|GCAttrMask|LifetimeMask);
-  static const uint32_t AddressSpaceShift = 8;
+  static const uint32_t UMask = 0x8;
+  static const uint32_t UShift = 3;
+  static const uint32_t GCAttrMask = 0x30;
+  static const uint32_t GCAttrShift = 4;
+  static const uint32_t LifetimeMask = 0x1C0;
+  static const uint32_t LifetimeShift = 6;
+  static const uint32_t AddressSpaceMask =
+      ~(CVRMask | UMask | GCAttrMask | LifetimeMask);
+  static const uint32_t AddressSpaceShift = 9;
 };
 
 /// A std::pair-like structure for storing a qualified type split
 /// into its local qualifiers and its locally-unqualified type.
 struct SplitQualType {
   /// The locally-unqualified type.
   const Type *Ty;
 

cfe/trunk/include/clang/Basic/AddressSpaces.h

 
 namespace LangAS {
 
 /// \brief Defines the set of possible language-specific address spaces.
 ///
 /// This uses a high starting offset so as not to conflict with any address
 /// space used by a target.
 enum ID {
-  Offset = 0xFFFF00,
+  Offset = 0x7FFF00,
 
   opencl_global = Offset,
   opencl_local,
   opencl_constant,
   opencl_generic,
 
   cuda_device,
   cuda_constant,

cfe/trunk/include/clang/Basic/Attr.td

def InitSeg : Attr {
   let Documentation = [InitSegDocs];
   let AdditionalMembers = [{
   void printPrettyPragma(raw_ostream &OS, const PrintingPolicy &Policy) const {
     OS << '(' << getSection() << ')';
   }
   }];
 }
 
-def Unaligned : IgnoredAttr {
-  let Spellings = [Keyword<"__unaligned">];
-}
-
 def LoopHint : Attr {
   /// #pragma clang loop <option> directive
   /// vectorize: vectorizes loop operations if State == Enable.
   /// vectorize_width: vectorize loop operations with width 'Value'.
   /// interleave: interleave multiple loop iterations if State == Enable.
   /// interleave_count: interleaves 'Value' loop interations.
   /// unroll: fully unroll loop if State == Enable.
   /// unroll_count: unrolls loop 'Value' times.

cfe/trunk/include/clang/Sema/DeclSpec.h

#include "clang/Basic/OpenCLImageTypes.def"
   // type-qualifiers
   enum TQ {   // NOTE: These flags must be kept in sync with Qualifiers::TQ.
     TQ_unspecified = 0,
     TQ_const       = 1,
     TQ_restrict    = 2,
     TQ_volatile    = 4,
     // This has no corresponding Qualifiers::TQ value, because it's not treated
     // as a qualifier in our type system.
-    TQ_atomic      = 8
-  };
+    TQ_atomic      = 8,
+    // There is no corresponding Qualifiers::TQ value, but it's kept separately
+    // in a dedicated Qualifiers::Mask bit.
+    TQ_unaligned   = 16 };
 
   /// ParsedSpecifiers - Flags to query which specifiers were applied.  This is
   /// returned by getParsedSpecifiers.
   enum ParsedSpecifiers {
     PQ_None                  = 0,
     PQ_StorageClassSpecifier = 1,
     PQ_TypeSpecifier         = 2,
     PQ_TypeQualifier         = 4,
private:
   /*TST*/unsigned TypeSpecType : 6;
   unsigned TypeAltiVecVector : 1;
   unsigned TypeAltiVecPixel : 1;
   unsigned TypeAltiVecBool : 1;
   unsigned TypeSpecOwned : 1;
   unsigned TypeSpecPipe : 1;
 
   // type-qualifiers
-  unsigned TypeQualifiers : 4;  // Bitwise OR of TQ.
+  unsigned TypeQualifiers : 5;  // Bitwise OR of TQ.
 
   // function-specifier
   unsigned FS_inline_specified : 1;
   unsigned FS_forceinline_specified: 1;
   unsigned FS_virtual_specified : 1;
   unsigned FS_explicit_specified : 1;
   unsigned FS_noreturn_specified : 1;
 
private:
   SourceLocation StorageClassSpecLoc, ThreadStorageClassSpecLoc;
   SourceLocation TSWLoc, TSCLoc, TSSLoc, TSTLoc, AltiVecLoc;
   /// TSTNameLoc - If TypeSpecType is any of class, enum, struct, union,
   /// typename, then this is the location of the named type (if present);
   /// otherwise, it is the same as TSTLoc. Hence, the pair TSTLoc and
   /// TSTNameLoc provides source range info for tag types.
   SourceLocation TSTNameLoc;
   SourceRange TypeofParensRange;
-  SourceLocation TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc;
+  SourceLocation TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc,
+      TQ_unalignedLoc;
   SourceLocation FS_inlineLoc, FS_virtualLoc, FS_explicitLoc, FS_noreturnLoc;
   SourceLocation FS_forceinlineLoc;
   SourceLocation FriendLoc, ModulePrivateLoc, ConstexprLoc, ConceptLoc;
   SourceLocation TQ_pipeLoc;
 
   WrittenBuiltinSpecs writtenBS;
   void SaveWrittenBuiltinSpecs();
 
public:
   // type-qualifiers
 
   /// getTypeQualifiers - Return a set of TQs.
   unsigned getTypeQualifiers() const { return TypeQualifiers; }
   SourceLocation getConstSpecLoc() const { return TQ_constLoc; }
   SourceLocation getRestrictSpecLoc() const { return TQ_restrictLoc; }
   SourceLocation getVolatileSpecLoc() const { return TQ_volatileLoc; }
   SourceLocation getAtomicSpecLoc() const { return TQ_atomicLoc; }
+  SourceLocation getUnalignedSpecLoc() const { return TQ_unalignedLoc; }
   SourceLocation getPipeLoc() const { return TQ_pipeLoc; }
 
   /// \brief Clear out all of the type qualifiers.
   void ClearTypeQualifiers() {
     TypeQualifiers = 0;
     TQ_constLoc = SourceLocation();
     TQ_restrictLoc = SourceLocation();
     TQ_volatileLoc = SourceLocation();
     TQ_atomicLoc = SourceLocation();
+    TQ_unalignedLoc = SourceLocation();
     TQ_pipeLoc = SourceLocation();
   }
 
   // function-specifier
   bool isInlineSpecified() const {
     return FS_inline_specified | FS_forceinline_specified;
   }
   SourceLocation getInlineSpecLoc() const {
SourceRange getSourceRange() const {
     return SourceRange(Loc, EndLoc);
   }
 
   struct TypeInfoCommon {
     AttributeList *AttrList;
   };
 
   struct PointerTypeInfo : TypeInfoCommon {
-    /// The type qualifiers: const/volatile/restrict/atomic.
-    unsigned TypeQuals : 4;
+    /// The type qualifiers: const/volatile/restrict/atomic/unaligned.
+    unsigned TypeQuals : 5;
 
     /// The location of the const-qualifier, if any.
     unsigned ConstQualLoc;
 
     /// The location of the volatile-qualifier, if any.
     unsigned VolatileQualLoc;
 
     /// The location of the restrict-qualifier, if any.
     unsigned RestrictQualLoc;
 
     /// The location of the _Atomic-qualifier, if any.
     unsigned AtomicQualLoc;
 
+    /// The location of the __unaligned-qualifier, if any.
+    unsigned UnalignedQualLoc;
+
     void destroy() {
     }
   };
 
   struct ReferenceTypeInfo : TypeInfoCommon {
     /// The type qualifier: restrict. [GNU] C++ extension
     bool HasRestrict : 1;
     /// True if this is an lvalue reference, false if it's an rvalue reference.
AttributeList *&getAttrListRef() {
     return Common.AttrList;
   }
 
   /// \brief Return a DeclaratorChunk for a pointer.
   static DeclaratorChunk getPointer(unsigned TypeQuals, SourceLocation Loc,
                                     SourceLocation ConstQualLoc,
                                     SourceLocation VolatileQualLoc,
                                     SourceLocation RestrictQualLoc,
-                                    SourceLocation AtomicQualLoc) {
+                                    SourceLocation AtomicQualLoc,
+                                    SourceLocation UnalignedQualLoc) {
     DeclaratorChunk I;
     I.Kind                = Pointer;
     I.Loc                 = Loc;
     I.Ptr.TypeQuals       = TypeQuals;
     I.Ptr.ConstQualLoc    = ConstQualLoc.getRawEncoding();
     I.Ptr.VolatileQualLoc = VolatileQualLoc.getRawEncoding();
     I.Ptr.RestrictQualLoc = RestrictQualLoc.getRawEncoding();
     I.Ptr.AtomicQualLoc   = AtomicQualLoc.getRawEncoding();
+    I.Ptr.UnalignedQualLoc = UnalignedQualLoc.getRawEncoding();
     I.Ptr.AttrList        = nullptr;
     return I;
   }
 
   /// \brief Return a DeclaratorChunk for a reference.
   static DeclaratorChunk getReference(unsigned TypeQuals, SourceLocation Loc,
                                       bool lvalue) {
     DeclaratorChunk I;

cfe/trunk/include/clang/Sema/Sema.h

bool diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
                                     DeclarationName Name,
                                     SourceLocation Loc);
   void
   diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
                             SourceLocation FallbackLoc,
                             SourceLocation ConstQualLoc = SourceLocation(),
                             SourceLocation VolatileQualLoc = SourceLocation(),
                             SourceLocation RestrictQualLoc = SourceLocation(),
-                            SourceLocation AtomicQualLoc = SourceLocation());
+                            SourceLocation AtomicQualLoc = SourceLocation(),
+                            SourceLocation UnalignedQualLoc = SourceLocation());
 
   static bool adjustContextForLocalExternDecl(DeclContext *&DC);
   void DiagnoseFunctionSpecifiers(const DeclSpec &DS);
   void CheckShadow(Scope *S, VarDecl *D, const LookupResult& R);
   void CheckShadow(Scope *S, VarDecl *D);
   void CheckCastAlign(Expr *Op, QualType T, SourceRange TRange);
   void handleTagNumbering(const TagDecl *Tag, Scope *TagScope);
   void setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,

cfe/trunk/lib/AST/MicrosoftMangle.cpp

 
 void MicrosoftCXXNameMangler::manglePointerExtQualifiers(Qualifiers Quals,
                                                          QualType PointeeType) {
   bool HasRestrict = Quals.hasRestrict();
   if (PointersAre64Bit &&
       (PointeeType.isNull() || !PointeeType->isFunctionType()))
     Out << 'E';
 
+  if (!PointeeType.isNull() && PointeeType.getLocalQualifiers().hasUnaligned())
+    Out << 'F';
+
   if (HasRestrict)
     Out << 'I';
 }
 
 void MicrosoftCXXNameMangler::manglePointerCVQualifiers(Qualifiers Quals) {
   // <pointer-cv-qualifiers> ::= P  # no qualifiers
   //                         ::= Q  # const
   //                         ::= R  # volatile
case QMM_Mangle:
     break;
   case QMM_Escape:
     if (!IsPointer && Quals) {
       Out << "$$C";
       mangleQualifiers(Quals, false);
     }
     break;
   case QMM_Result:
+    // Presence of __unaligned qualifier shouldn't affect mangling here.
+    Quals.removeUnaligned();
     if ((!IsPointer && Quals) || isa<TagType>(T)) {
       Out << '?';
       mangleQualifiers(Quals, false);
     }
     break;
   }
 
   const Type *ty = T.getTypePtr();

cfe/trunk/lib/AST/TypePrinter.cpp

void Qualifiers::print(raw_ostream &OS, const PrintingPolicy& Policy,
                        bool appendSpaceIfNonEmpty) const {
   bool addSpace = false;
 
   unsigned quals = getCVRQualifiers();
   if (quals) {
     AppendTypeQualList(OS, quals, Policy.LangOpts.C99);
     addSpace = true;
   }
+  if (hasUnaligned()) {
+    if (addSpace)
+      OS << ' ';
+    OS << "__unaligned";
+    addSpace = true;
+  }
   if (unsigned addrspace = getAddressSpace()) {
     if (addSpace)
       OS << ' ';
     addSpace = true;
     switch (addrspace) {
       case LangAS::opencl_global:
         OS << "__global";
         break;

cfe/trunk/lib/Parse/ParseDecl.cpp

while (true) {
     case tok::kw___fastcall:
     case tok::kw___stdcall:
     case tok::kw___thiscall:
     case tok::kw___cdecl:
     case tok::kw___vectorcall:
     case tok::kw___ptr64:
     case tok::kw___w64:
     case tok::kw___ptr32:
-    case tok::kw___unaligned:
     case tok::kw___sptr:
     case tok::kw___uptr: {
       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
       SourceLocation AttrNameLoc = ConsumeToken();
       attrs.addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc, nullptr, 0,
                    AttributeList::AS_Keyword);
       break;
     }
case tok::kw___forceinline: {
       isInvalid = DS.setFunctionSpecForceInline(Loc, PrevSpec, DiagID);
       IdentifierInfo *AttrName = Tok.getIdentifierInfo();
       SourceLocation AttrNameLoc = Tok.getLocation();
       DS.getAttributes().addNew(AttrName, AttrNameLoc, nullptr, AttrNameLoc,
                                 nullptr, 0, AttributeList::AS_Keyword);
       break;
     }
 
+    case tok::kw___unaligned:
+      isInvalid = DS.SetTypeQual(DeclSpec::TQ_unaligned, Loc, PrevSpec, DiagID,
+                                 getLangOpts());
+      break;
+
     case tok::kw___sptr:
     case tok::kw___uptr:
     case tok::kw___ptr64:
     case tok::kw___ptr32:
     case tok::kw___w64:
     case tok::kw___cdecl:
     case tok::kw___stdcall:
     case tok::kw___fastcall:
     case tok::kw___thiscall:
     case tok::kw___vectorcall:
-    case tok::kw___unaligned:
       ParseMicrosoftTypeAttributes(DS.getAttributes());
       continue;
 
     // Borland single token adornments.
     case tok::kw___pascal:
       ParseBorlandTypeAttributes(DS.getAttributes());
       continue;
 
while (1) {
     case tok::kw___constant:
     case tok::kw___generic:
     case tok::kw___read_only:
     case tok::kw___write_only:
     case tok::kw___read_write:
       ParseOpenCLQualifiers(DS.getAttributes());
       break;
 
+    case tok::kw___unaligned:
+      isInvalid = DS.SetTypeQual(DeclSpec::TQ_unaligned, Loc, PrevSpec, DiagID,
+                                 getLangOpts());
+      break;
     case tok::kw___uptr:
       // GNU libc headers in C mode use '__uptr' as an identifer which conflicts
       // with the MS modifier keyword.
       if ((AttrReqs & AR_DeclspecAttributesParsed) && !getLangOpts().CPlusPlus &&
           IdentifierRequired && DS.isEmpty() && NextToken().is(tok::semi)) {
         if (TryKeywordIdentFallback(false))
           continue;
       }
     case tok::kw___sptr:
     case tok::kw___w64:
     case tok::kw___ptr64:
     case tok::kw___ptr32:
     case tok::kw___cdecl:
     case tok::kw___stdcall:
     case tok::kw___fastcall:
     case tok::kw___thiscall:
     case tok::kw___vectorcall:
-    case tok::kw___unaligned:
       if (AttrReqs & AR_DeclspecAttributesParsed) {
         ParseMicrosoftTypeAttributes(DS.getAttributes());
         continue;
       }
       goto DoneWithTypeQuals;
     case tok::kw___pascal:
       if (AttrReqs & AR_VendorAttributesParsed) {
         ParseBorlandTypeAttributes(DS.getAttributes());
if (Kind == tok::star || Kind == tok::caret) {
     // Recursively parse the declarator.
     ParseDeclaratorInternal(D, DirectDeclParser);
     if (Kind == tok::star)
       // Remember that we parsed a pointer type, and remember the type-quals.
       D.AddTypeInfo(DeclaratorChunk::getPointer(DS.getTypeQualifiers(), Loc,
                                                 DS.getConstSpecLoc(),
                                                 DS.getVolatileSpecLoc(),
                                                 DS.getRestrictSpecLoc(),
-                                                DS.getAtomicSpecLoc()),
+                                                DS.getAtomicSpecLoc(),
+                                                DS.getUnalignedSpecLoc()),
                     DS.getAttributes(),
                     SourceLocation());
     else
       // Remember that we parsed a Block type, and remember the type-quals.
       D.AddTypeInfo(DeclaratorChunk::getBlockPointer(DS.getTypeQualifiers(),
                                                      Loc),
                     DS.getAttributes(),
                     SourceLocation());

cfe/trunk/lib/Parse/ParseTentative.cpp

if (mayBeAbstract &&
       if (TPR != TPResult::Ambiguous)
         return TPR;
     } else {
       // '(' declarator ')'
       // '(' attributes declarator ')'
       // '(' abstract-declarator ')'
       if (Tok.isOneOf(tok::kw___attribute, tok::kw___declspec, tok::kw___cdecl,
                       tok::kw___stdcall, tok::kw___fastcall, tok::kw___thiscall,
-                      tok::kw___vectorcall, tok::kw___unaligned))
+                      tok::kw___vectorcall))
         return TPResult::True; // attributes indicate declaration
       TPResult TPR = TryParseDeclarator(mayBeAbstract, mayHaveIdentifier);
       if (TPR != TPResult::Ambiguous)
         return TPR;
       if (Tok.isNot(tok::r_paren))
         return TPResult::False;
       ConsumeParen();
     }

cfe/trunk/lib/Sema/DeclSpec.cpp

 
 const char *DeclSpec::getSpecifierName(TQ T) {
   switch (T) {
   case DeclSpec::TQ_unspecified: return "unspecified";
   case DeclSpec::TQ_const:       return "const";
   case DeclSpec::TQ_restrict:    return "restrict";
   case DeclSpec::TQ_volatile:    return "volatile";
   case DeclSpec::TQ_atomic:      return "_Atomic";
+  case DeclSpec::TQ_unaligned:   return "__unaligned";
   }
   llvm_unreachable("Unknown typespec!");
 }
 
 bool DeclSpec::SetStorageClassSpec(Sema &S, SCS SC, SourceLocation Loc,
                                    const char *&PrevSpec,
                                    unsigned &DiagID,
                                    const PrintingPolicy &Policy) {
bool DeclSpec::SetTypeQual(TQ T, SourceLocation Loc, const char *&PrevSpec,
   TypeQualifiers |= T;
 
   switch (T) {
   case TQ_unspecified: break;
   case TQ_const:    TQ_constLoc = Loc; return false;
   case TQ_restrict: TQ_restrictLoc = Loc; return false;
   case TQ_volatile: TQ_volatileLoc = Loc; return false;
   case TQ_atomic:   TQ_atomicLoc = Loc; return false;
+  case TQ_unaligned: TQ_unalignedLoc = Loc; return false;
   }
 
   llvm_unreachable("Unknown type qualifier!");
 }
 
 bool DeclSpec::setFunctionSpecInline(SourceLocation Loc, const char *&PrevSpec,
                                      unsigned &DiagID) {
   // 'inline inline' is ok.  However, since this is likely not what the user
void DeclSpec::Finish(Sema &S, const PrintingPolicy &Policy) {
 
   // If decltype(auto) is used, no other type specifiers are permitted.
   if (TypeSpecType == TST_decltype_auto &&
       (TypeSpecWidth != TSW_unspecified ||
        TypeSpecComplex != TSC_unspecified ||
        TypeSpecSign != TSS_unspecified ||
        TypeAltiVecVector || TypeAltiVecPixel || TypeAltiVecBool ||
        TypeQualifiers)) {
-    const unsigned NumLocs = 8;
+    const unsigned NumLocs = 9;
     SourceLocation ExtraLocs[NumLocs] = {
       TSWLoc, TSCLoc, TSSLoc, AltiVecLoc,
-      TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc
+      TQ_constLoc, TQ_restrictLoc, TQ_volatileLoc, TQ_atomicLoc, TQ_unalignedLoc
     };
     FixItHint Hints[NumLocs];
     SourceLocation FirstLoc;
     for (unsigned I = 0; I != NumLocs; ++I) {
       if (ExtraLocs[I].isValid()) {
         if (FirstLoc.isInvalid() ||
             S.getSourceManager().isBeforeInTranslationUnit(ExtraLocs[I],
                                                            FirstLoc))

cfe/trunk/lib/Sema/SemaCodeComplete.cpp

void Sema::CodeCompleteTypeQualifiers(DeclSpec &DS) {
   if (!(DS.getTypeQualifiers() & DeclSpec::TQ_volatile))
     Results.AddResult("volatile");
   if (getLangOpts().C99 &&
       !(DS.getTypeQualifiers() & DeclSpec::TQ_restrict))
     Results.AddResult("restrict");
   if (getLangOpts().C11 &&
       !(DS.getTypeQualifiers() & DeclSpec::TQ_atomic))
     Results.AddResult("_Atomic");
+  if (getLangOpts().MSVCCompat &&
+      !(DS.getTypeQualifiers() & DeclSpec::TQ_unaligned))
+    Results.AddResult("__unaligned");
   Results.ExitScope();
   HandleCodeCompleteResults(this, CodeCompleter, 
                             Results.getCompletionContext(),
                             Results.data(), Results.size());
 }
 
 void Sema::CodeCompleteBracketDeclarator(Scope *S) {
   CodeCompleteExpression(S, QualType(getASTContext().getSizeType()));

cfe/trunk/lib/Sema/SemaDecl.cpp

Sema::ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
   if (DS.getTypeQualifiers()) {
     if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
       Diag(DS.getConstSpecLoc(), DiagID) << "const";
     if (DS.getTypeQualifiers() & DeclSpec::TQ_volatile)
       Diag(DS.getConstSpecLoc(), DiagID) << "volatile";
     // Restrict is covered above.
     if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
       Diag(DS.getAtomicSpecLoc(), DiagID) << "_Atomic";
+    if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
+      Diag(DS.getUnalignedSpecLoc(), DiagID) << "__unaligned";
   }
 
   // Warn about ignored type attributes, for example:
   // __attribute__((aligned)) struct A;
   // Attributes should be placed after tag to apply to type declaration.
   if (!DS.getAttributes().empty()) {
     DeclSpec::TST TypeSpecType = DS.getTypeSpecType();
     if (TypeSpecType == DeclSpec::TST_class ||
if (DS.getTypeQualifiers()) {
              diag::ext_anonymous_struct_union_qualified)
           << Record->isUnion() << "restrict"
           << FixItHint::CreateRemoval(DS.getRestrictSpecLoc());
       if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
         Diag(DS.getAtomicSpecLoc(),
              diag::ext_anonymous_struct_union_qualified)
           << Record->isUnion() << "_Atomic"
           << FixItHint::CreateRemoval(DS.getAtomicSpecLoc());
+      if (DS.getTypeQualifiers() & DeclSpec::TQ_unaligned)
+        Diag(DS.getUnalignedSpecLoc(),
+             diag::ext_anonymous_struct_union_qualified)
+          << Record->isUnion() << "__unaligned"
+          << FixItHint::CreateRemoval(DS.getUnalignedSpecLoc());
 
       DS.ClearTypeQualifiers();
     }
 
     // C++ [class.union]p2:
     //   The member-specification of an anonymous union shall only
     //   define non-static data members. [Note: nested types and
     //   functions cannot be declared within an anonymous union. ]

cfe/trunk/lib/Sema/SemaDeclObjC.cpp

auto resolveTypeReference = [&](TypeOrClassDecl typeDecl, SourceLocation loc)
     // add the '*'.
     if (type->getAs<ObjCInterfaceType>()) {
       SourceLocation starLoc = getLocForEndOfToken(loc);
       ParsedAttributes parsedAttrs(attrFactory);
       D.AddTypeInfo(DeclaratorChunk::getPointer(/*typeQuals=*/0, starLoc,
                                                 SourceLocation(),
                                                 SourceLocation(),
                                                 SourceLocation(),
+                                                SourceLocation(),
                                                 SourceLocation()),
                                                 parsedAttrs,
                                                 starLoc);
 
       // Diagnose the missing '*'.
       Diag(loc, diag::err_objc_type_arg_missing_star)
         << type
         << FixItHint::CreateInsertion(starLoc, " *");

cfe/trunk/lib/Sema/SemaExpr.cpp

else if (lhq.withoutObjCGCAttr().withoutObjCLifetime()
                                 rhq.withoutObjCGCAttr().withoutObjCLifetime())
              && (lhptee->isVoidType() || rhptee->isVoidType()))
       ; // keep old
 
     // Treat lifetime mismatches as fatal.
     else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
       ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
     
-    // For GCC compatibility, other qualifier mismatches are treated
+    // For GCC/MS compatibility, other qualifier mismatches are treated
     // as still compatible in C.
     else ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
   }
 
   // C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
   // incomplete type and the other is a pointer to a qualified or unqualified
   // version of void...
   if (lhptee->isVoidType()) {

cfe/trunk/lib/Sema/SemaType.cpp

if (DiagID) {
       Qs.removeRestrict();
     }
   }
 
   return Context.getQualifiedType(T, Qs);
 }
 
 QualType Sema::BuildQualifiedType(QualType T, SourceLocation Loc,
-                                  unsigned CVRA, const DeclSpec *DS) {
+                                  unsigned CVRAU, const DeclSpec *DS) {
   if (T.isNull())
     return QualType();
 
-  // Convert from DeclSpec::TQ to Qualifiers::TQ by just dropping TQ_atomic.
-  unsigned CVR = CVRA & ~DeclSpec::TQ_atomic;
+  // Convert from DeclSpec::TQ to Qualifiers::TQ by just dropping TQ_atomic and
+  // TQ_unaligned;
+  unsigned CVR = CVRAU & ~DeclSpec::TQ_atomic & ~DeclSpec::TQ_unaligned;
 
   // C11 6.7.3/5:
   //   If the same qualifier appears more than once in the same
   //   specifier-qualifier-list, either directly or via one or more typedefs,
   //   the behavior is the same as if it appeared only once.
   //
   // It's not specified what happens when the _Atomic qualifier is applied to
   // a type specified with the _Atomic specifier, but we assume that this
   // should be treated as if the _Atomic qualifier appeared multiple times.
-  if (CVRA & DeclSpec::TQ_atomic && !T->isAtomicType()) {
+  if (CVRAU & DeclSpec::TQ_atomic && !T->isAtomicType()) {
     // C11 6.7.3/5:
     //   If other qualifiers appear along with the _Atomic qualifier in a
     //   specifier-qualifier-list, the resulting type is the so-qualified
     //   atomic type.
     //
     // Don't need to worry about array types here, since _Atomic can't be
     // applied to such types.
     SplitQualType Split = T.getSplitUnqualifiedType();
     T = BuildAtomicType(QualType(Split.Ty, 0),
                         DS ? DS->getAtomicSpecLoc() : Loc);
     if (T.isNull())
       return T;
     Split.Quals.addCVRQualifiers(CVR);
     return BuildQualifiedType(T, Loc, Split.Quals);
   }
 
-  return BuildQualifiedType(T, Loc, Qualifiers::fromCVRMask(CVR), DS);
+  Qualifiers Q = Qualifiers::fromCVRMask(CVR);
+  Q.setUnaligned(CVRAU & DeclSpec::TQ_unaligned);
+  return BuildQualifiedType(T, Loc, Q, DS);
 }
 
 /// \brief Build a paren type including \p T.
 QualType Sema::BuildParenType(QualType T) {
   return Context.getParenType(T);
 }
 
 /// Given that we're building a pointer or reference to the given
done:
   // TODO: mark whether we did this inference?
 }
 
 void Sema::diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
                                      SourceLocation FallbackLoc,
                                      SourceLocation ConstQualLoc,
                                      SourceLocation VolatileQualLoc,
                                      SourceLocation RestrictQualLoc,
-                                     SourceLocation AtomicQualLoc) {
+                                     SourceLocation AtomicQualLoc,
+                                     SourceLocation UnalignedQualLoc) {
   if (!Quals)
     return;
 
   struct Qual {
     const char *Name;
     unsigned Mask;
     SourceLocation Loc;
-  } const QualKinds[4] = {
+  } const QualKinds[5] = {
     { "const", DeclSpec::TQ_const, ConstQualLoc },
     { "volatile", DeclSpec::TQ_volatile, VolatileQualLoc },
     { "restrict", DeclSpec::TQ_restrict, RestrictQualLoc },
-    { "_Atomic", DeclSpec::TQ_atomic, AtomicQualLoc }
+    { "_Atomic", DeclSpec::TQ_atomic, AtomicQualLoc },
+    { "__unaligned", DeclSpec::TQ_unaligned, UnalignedQualLoc }
   };
 
   SmallString<32> QualStr;
   unsigned NumQuals = 0;
   SourceLocation Loc;
-  FixItHint FixIts[4];
+  FixItHint FixIts[5];
 
   // Build a string naming the redundant qualifiers.
-  for (unsigned I = 0; I != 4; ++I) {
+  for (unsigned I = 0; I != 5; ++I) {
     if (Quals & QualKinds[I].Mask) {
       if (!QualStr.empty()) QualStr += ' ';
       QualStr += QualKinds[I].Name;
 
       // If we have a location for the qualifier, offer a fixit.
       SourceLocation QualLoc = QualKinds[I].Loc;
       if (QualLoc.isValid()) {
         FixIts[NumQuals] = FixItHint::CreateRemoval(QualLoc);
case DeclaratorChunk::Pointer: {
       DeclaratorChunk::PointerTypeInfo &PTI = OuterChunk.Ptr;
       S.diagnoseIgnoredQualifiers(
           diag::warn_qual_return_type,
           PTI.TypeQuals,
           SourceLocation(),
           SourceLocation::getFromRawEncoding(PTI.ConstQualLoc),
           SourceLocation::getFromRawEncoding(PTI.VolatileQualLoc),
           SourceLocation::getFromRawEncoding(PTI.RestrictQualLoc),
-          SourceLocation::getFromRawEncoding(PTI.AtomicQualLoc));
+          SourceLocation::getFromRawEncoding(PTI.AtomicQualLoc),
+          SourceLocation::getFromRawEncoding(PTI.UnalignedQualLoc));
       return;
     }
 
     case DeclaratorChunk::Function:
     case DeclaratorChunk::BlockPointer:
     case DeclaratorChunk::Reference:
     case DeclaratorChunk::Array:
     case DeclaratorChunk::MemberPointer:
static void diagnoseRedundantReturnTypeQualifiers(Sema &S, QualType RetTy,
   // Just parens all the way out to the decl specifiers. Diagnose any qualifiers
   // which are present there.
   S.diagnoseIgnoredQualifiers(diag::warn_qual_return_type,
                               D.getDeclSpec().getTypeQualifiers(),
                               D.getIdentifierLoc(),
                               D.getDeclSpec().getConstSpecLoc(),
                               D.getDeclSpec().getVolatileSpecLoc(),
                               D.getDeclSpec().getRestrictSpecLoc(),
-                              D.getDeclSpec().getAtomicSpecLoc());
+                              D.getDeclSpec().getAtomicSpecLoc(),
+                              D.getDeclSpec().getUnalignedSpecLoc());
 }
 
 static QualType GetDeclSpecTypeForDeclarator(TypeProcessingState &state,
                                              TypeSourceInfo *&ReturnTypeInfo) {
   Sema &SemaRef = state.getSema();
   Declarator &D = state.getDeclarator();
   QualType T;
   ReturnTypeInfo = nullptr;

cfe/trunk/test/CodeGenCXX/mangle-ms-cxx11.cpp

 }
 
 int PR26105() {
   auto add = [](int x) { return ([x](int y) { return x + y; }); };
   return add(3)(4);
 }
 // CHECK-DAG: @"\01??R<lambda_0>@?0??PR26105@@YAHXZ@QBE@H@Z"
 // CHECK-DAG: @"\01??R<lambda_1>@?0???R<lambda_0>@?0??PR26105@@YAHXZ@QBE@H@Z@QBE@H@Z"
+
+int __unaligned * unaligned_foo1() { return 0; }
+int __unaligned * __unaligned * unaligned_foo2() { return 0; }
+__unaligned int unaligned_foo3() { return 0; }
+void unaligned_foo4(int __unaligned *p1) {}
+
+// CHECK-DAG: @"\01?unaligned_foo1@@YAPFAHXZ"
+// CHECK-DAG: @"\01?unaligned_foo2@@YAPFAPFAHXZ"
+// CHECK-DAG: @"\01?unaligned_foo3@@YAHXZ"
+// CHECK-DAG: @"\01?unaligned_foo4@@YAXPFAH@Z"
+

cfe/trunk/test/Sema/MicrosoftExtensions.c

void myprintf(const char *f, ...) {
   if (1) {
     __va_start(&ap, f);
     vmyprintf(f, ap);
     ap = 0;
   } else {
     __va_start(ap, f); // expected-warning {{incompatible pointer types passing 'my_va_list'}}
   }
 }
+
+// __unaligned handling
+void test_unaligned() {
+  __unaligned int *p1 = 0;
+  int *p2 = p1; // expected-warning {{initializing 'int *' with an expression of type '__unaligned int *' discards qualifiers}}
+  __unaligned int *p3 = p2;
+}
+

cfe/trunk/test/Sema/address_spaces.c

void foo(_AS3 float *a,
   int _AS1 _AS2 *Y;   // expected-error {{multiple address spaces specified for type}}
   int *_AS1 _AS2 *Z;  // expected-error {{multiple address spaces specified for type}}
 
   _AS1 int local;     // expected-error {{automatic variable qualified with an address space}}
   _AS1 int array[5];  // expected-error {{automatic variable qualified with an address space}}
   _AS1 int arrarr[5][5]; // expected-error {{automatic variable qualified with an address space}}
 
   __attribute__((address_space(-1))) int *_boundsA; // expected-error {{address space is negative}}
-  __attribute__((address_space(0xFFFFFF))) int *_boundsB;
+  __attribute__((address_space(0x7FFFFF))) int *_boundsB;
   __attribute__((address_space(0x1000000))) int *_boundsC; // expected-error {{address space is larger than the maximum supported}}
   // chosen specifically to overflow 32 bits and come out reasonable
   __attribute__((address_space(4294967500))) int *_boundsD; // expected-error {{address space is larger than the maximum supported}}
 
   *a = 5.0f + b;
 }
 
 struct _st {

 }
 
 typedef int PR4997 __attribute__((address_space(Foobar))); // expected-error {{use of undeclared identifier 'Foobar'}}
 __attribute__((address_space("12"))) int *i; // expected-error {{'address_space' attribute requires an integer constant}}
 
 // Clang extension doesn't forbid operations on pointers to different address spaces.
 char* cmp(_AS1 char *x,  _AS2 char *y) {
   return x < y ? x : y; // expected-warning {{pointer type mismatch ('__attribute__((address_space(1))) char *' and '__attribute__((address_space(2))) char *')}}
-}
+}
 

cfe/trunk/test/Sema/invalid-assignment-constant-address-space.c

 // RUN: %clang_cc1 %s -verify -pedantic -fsyntax-only
 
-#define OPENCL_CONSTANT 16776962
+#define OPENCL_CONSTANT 8388354
 int __attribute__((address_space(OPENCL_CONSTANT))) c[3] = {0};
 
 void foo() {
   c[0] = 1; //expected-error{{read-only variable is not assignable}}
 }

cfe/trunk/test/SemaCXX/MicrosoftExtensions.cpp

-// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify -fms-extensions -fexceptions -fcxx-exceptions
+// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify -fms-extensions -fexceptions -fcxx-exceptions -DTEST1
+// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -Wmicrosoft -Wc++11-extensions -Wno-long-long -verify -fexceptions -fcxx-exceptions -DTEST2
 
+#if TEST1
 
 // Microsoft doesn't validate exception specification.
 namespace microsoft_exception_spec {
 
 void foo(); // expected-note {{previous declaration}}
 void foo() throw(); // expected-warning {{exception specification in declaration does not match previous declaration}}
 
 void r6() throw(...); // expected-note {{previous declaration}}

 struct M {
     int __stdcall addP();
     float __stdcall subtractP();
 };
 
 // __unaligned handling
 typedef char __unaligned *aligned_type;
 typedef struct UnalignedTag { int f; } __unaligned *aligned_type2;
+typedef char __unaligned aligned_type3;
 
+// Check that __unaligned qualifier can be used for overloading
+void foo_unaligned(int *arg) {}
+void foo_unaligned(__unaligned int *arg) {}
+void foo_unaligned(int arg) {} // expected-note {{previous definition is here}}
+void foo_unaligned(__unaligned int arg) {} // expected-error {{redefinition of 'foo_unaligned'}}
+class A_unaligned {};
+class B_unaligned : public A_unaligned {};
+int foo_unaligned(__unaligned A_unaligned *arg) { return 0; }
+void *foo_unaligned(B_unaligned *arg) { return 0; }
+
+void test_unaligned() {
+  int *p1 = 0;
+  foo_unaligned(p1);
+
+  __unaligned int *p2 = 0;
+  foo_unaligned(p2);
+
+  __unaligned B_unaligned *p3 = 0;
+  int p4 = foo_unaligned(p3);
+
+  B_unaligned *p5 = p3; // expected-error {{cannot initialize a variable of type 'B_unaligned *' with an lvalue of type '__unaligned B_unaligned *'}}
+
+  __unaligned B_unaligned *p6 = p3;
+}
 
 template<typename T> void h1(T (__stdcall M::* const )()) { }
 
 void m1() {
   h1<int>(&M::addP);
   h1(&M::subtractP);
 }
 

 
 namespace PR25265 {
 struct S {
   int fn() throw(); // expected-note {{previous declaration is here}}
 };
 
 int S::fn() { return 0; } // expected-warning {{is missing exception specification}}
 }
+
+#elif TEST2
+
+// Check that __unaligned is not recognized if MS extensions are not enabled
+typedef char __unaligned *aligned_type; // expected-error {{expected ';' after top level declarator}}
+
+#else
+
+#error Unknown test mode
+
+#endif
+