1 files changed, 31 insertions, 5 deletions

diff --git a/lib/Sema/SemaStmtAttr.cpp b/lib/Sema/SemaStmtAttr.cpp
index 21c3297..3c15b7a 100644
--- a/lib/Sema/SemaStmtAttr.cpp
+++ b/lib/Sema/SemaStmtAttr.cpp
@@ -15,29 +15,55 @@
 #include "TargetAttributesSema.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/Basic/SourceManager.h"
+#include "clang/Lex/Lexer.h"
 #include "clang/Sema/DelayedDiagnostic.h"
 #include "clang/Sema/Lookup.h"
+#include "clang/Sema/ScopeInfo.h"
 #include "llvm/ADT/StringExtras.h"
+
 using namespace clang;
 using namespace sema;
 
+static Attr *handleFallThroughAttr(Sema &S, Stmt *St, const AttributeList &A,
+                                   SourceRange Range) {
+  if (!isa<NullStmt>(St)) {
+    S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_wrong_target)
+        << St->getLocStart();
+    if (isa<SwitchCase>(St)) {
+      SourceLocation L = Lexer::getLocForEndOfToken(Range.getEnd(), 0,
+                                  S.getSourceManager(), S.getLangOpts());
+      S.Diag(L, diag::note_fallthrough_insert_semi_fixit)
+          << FixItHint::CreateInsertion(L, ";");
+    }
+    return 0;
+  }
+  if (S.getCurFunction()->SwitchStack.empty()) {
+    S.Diag(A.getRange().getBegin(), diag::err_fallthrough_attr_outside_switch);
+    return 0;
+  }
+  return ::new (S.Context) FallThroughAttr(A.getRange(), S.Context);
+}
+
 
-static Attr *ProcessStmtAttribute(Sema &S, Stmt *St, const AttributeList &A) {
+static Attr *ProcessStmtAttribute(Sema &S, Stmt *St, const AttributeList &A,
+                                  SourceRange Range) {
   switch (A.getKind()) {
+  case AttributeList::AT_FallThrough:
+    return handleFallThroughAttr(S, St, A, Range);
   default:
     // if we're here, then we parsed an attribute, but didn't recognize it as a
     // statement attribute => it is declaration attribute
-    S.Diag(A.getRange().getBegin(), diag::warn_attribute_invalid_on_stmt) <<
-      A.getName()->getName();
+    S.Diag(A.getRange().getBegin(), diag::warn_attribute_invalid_on_stmt)
+        << A.getName()->getName() << St->getLocStart();
     return 0;
   }
 }
 
 StmtResult Sema::ProcessStmtAttributes(Stmt *S, AttributeList *AttrList,
                                        SourceRange Range) {
-  AttrVec Attrs;
+  SmallVector<const Attr*, 8> Attrs;
   for (const AttributeList* l = AttrList; l; l = l->getNext()) {
-    if (Attr *a = ProcessStmtAttribute(*this, S, *l))
+    if (Attr *a = ProcessStmtAttribute(*this, S, *l, Range))
       Attrs.push_back(a);
   }