Fix crash with -ast-dump in C++.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@61108 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Driver/ASTConsumers.cpp b/Driver/ASTConsumers.cpp
index 9254d80..cc41642 100644
--- a/Driver/ASTConsumers.cpp
+++ b/Driver/ASTConsumers.cpp
@@ -490,8 +490,9 @@
         Out << "Read objc implementation decl\n";
       } else if (isa<ObjCCategoryImplDecl>(D)) {
         Out << "Read objc category implementation decl\n";
-      }
-      else {
+      } else if (isa<LinkageSpecDecl>(D)) {
+        Out << "Read linkage spec decl\n";
+      } else {
         assert(0 && "Unknown decl type!");
       }
     }