Teach serialized diagnostics about notes without locations.

Along the way, improve a diagnostic for "previous declaration here" for implicit parameters.

Fixes <rdar://problem/13211384>.

llvm-svn: 175802

2 files changed, 17 insertions, 2 deletions

diff --git a/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp b/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
index 8eb0e40..4bb662b 100644
--- a/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
+++ b/clang/lib/Frontend/SerializedDiagnosticPrinter.cpp
@@ -543,8 +543,18 @@ void SDiagsWriter::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
     // Special-case diagnostics with no location. We may not have entered a
     // source file in this case, so we can't use the normal DiagnosticsRenderer
     // machinery.
+
+    // Make sure we bracket all notes as "sub-diagnostics".  This matches
+    // the behavior in SDiagsRenderer::emitDiagnostic().
+    if (DiagLevel == DiagnosticsEngine::Note)
+      EnterDiagBlock();
+
     EmitDiagnosticMessage(SourceLocation(), PresumedLoc(), DiagLevel,
                           State->diagBuf, 0, &Info);
+
+    if (DiagLevel == DiagnosticsEngine::Note)
+      ExitDiagBlock();
+
     return;
   }
 
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 2858f36..7411e80 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -1672,9 +1672,14 @@ bool Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
             << SS.getRange()
             << FixItHint::CreateReplacement(Corrected.getCorrectionRange(),
                                             CorrectedStr);
-        if (ND)
-          Diag(ND->getLocation(), diag::note_previous_decl)
+        if (ND) {
+          unsigned diag = isa<ImplicitParamDecl>(ND)
+            ? diag::note_implicit_param_decl
+            : diag::note_previous_decl;
+
+          Diag(ND->getLocation(), diag)
             << CorrectedQuotedStr;
+        }
 
         // Tell the callee to try to recover.
         return false;