[MSVC] Implementation of __unaligned as a proper type qualifier

This patch implements __unaligned (MS extension) as a proper type qualifier
(before that, it was implemented as an ignored attribute).

It also fixes PR27367 and PR27666.

Differential Revision: http://reviews.llvm.org/D20103

llvm-svn: 269220

clang/lib/Sema/SemaCodeComplete.cpp

@@ -3812,6 +3812,9 @@ void Sema::CodeCompleteTypeQualifiers(DeclSpec &DS) {
   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(),