Add a fixit for removal of unused label.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@136389 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 17 insertions, 1 deletions

diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 321ab780d4..4988323f41 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1086,12 +1086,28 @@ static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) {
   return true;
 }
 
+static void GenerateFixForUnusedDecl(const NamedDecl *D, ASTContext &Ctx,
+                                     FixItHint &Hint) {
+  if (isa<LabelDecl>(D)) {
+    SourceLocation AfterColon = Lexer::findLocationAfterToken(D->getLocEnd(),
+                tok::colon, Ctx.getSourceManager(), Ctx.getLangOptions(), true);
+    if (AfterColon.isInvalid())
+      return;
+    Hint = FixItHint::CreateRemoval(CharSourceRange::
+                                    getCharRange(D->getLocStart(), AfterColon));
+  }
+  return;
+}
+
 /// DiagnoseUnusedDecl - Emit warnings about declarations that are not used
 /// unless they are marked attr(unused).
 void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
+  FixItHint Hint;
   if (!ShouldDiagnoseUnusedDecl(D))
     return;
   
+  GenerateFixForUnusedDecl(D, Context, Hint);
+
   unsigned DiagID;
   if (isa<VarDecl>(D) && cast<VarDecl>(D)->isExceptionVariable())
     DiagID = diag::warn_unused_exception_param;
@@ -1100,7 +1116,7 @@ void Sema::DiagnoseUnusedDecl(const NamedDecl *D) {
   else
     DiagID = diag::warn_unused_variable;
 
-  Diag(D->getLocation(), DiagID) << D->getDeclName();
+  Diag(D->getLocation(), DiagID) << D->getDeclName() << Hint;
 }
 
 static void CheckPoppedLabel(LabelDecl *L, Sema &S) {