From 1d86ab4d362655fee7c9dd80c2d1c9342d982a73 Mon Sep 17 00:00:00 2001
From: Alex Lorenz <arphaman@gmail.com>
Date: Tue, 3 Jan 2017 12:08:40 +0000
Subject: [PATCH] Handle UsingDecl and UsingShadowDecl in DeclContextPrinter

This commit fixes a crash that occurs when -print-decl-contexts AST consumer
tries to print an unhandled declaration.

rdar://19467234

Differential Revision: https://reviews.llvm.org/D26964

llvm-svn: 290881
---
 clang/lib/Frontend/ASTConsumers.cpp           | 8 ++++++++
 clang/test/Coverage/cxx-language-features.inc | 8 ++++++++
 2 files changed, 16 insertions(+)

diff --git a/clang/lib/Frontend/ASTConsumers.cpp b/clang/lib/Frontend/ASTConsumers.cpp
index 329f15fbef1f..2bb78b3d3069 100644
--- a/clang/lib/Frontend/ASTConsumers.cpp
+++ b/clang/lib/Frontend/ASTConsumers.cpp
@@ -485,6 +485,14 @@ void DeclContextPrinter::PrintDeclContext(const DeclContext* DC,
       Out << "\n";
       break;
     }
+    case Decl::Using: {
+      Out << "<using> " << *cast<UsingDecl>(I) << "\n";
+      break;
+    }
+    case Decl::UsingShadow: {
+      Out << "<using shadow> " << *cast<UsingShadowDecl>(I) << "\n";
+      break;
+    }
     default:
       Out << "DeclKind: " << DK << '"' << I << "\"\n";
       llvm_unreachable("decl unhandled");
diff --git a/clang/test/Coverage/cxx-language-features.inc b/clang/test/Coverage/cxx-language-features.inc
index 18e28e0fabce..0652d6980a93 100644
--- a/clang/test/Coverage/cxx-language-features.inc
+++ b/clang/test/Coverage/cxx-language-features.inc
@@ -33,3 +33,11 @@ struct FriendlyStruct {
 };
 
 struct FriendedStruct { };
+
+// Using declaration
+namespace provider {
+  void foo();
+}
+namespace user {
+  using provider::foo;
+}