1 files changed, 1 insertions, 3 deletions
diff --git a/csharp/src/Google.Protobuf/WellKnownTypes/SourceContext.cs b/csharp/src/Google.Protobuf/WellKnownTypes/SourceContext.cs
index 5566b5ce..ae79884f 100644
--- a/csharp/src/Google.Protobuf/WellKnownTypes/SourceContext.cs
+++ b/csharp/src/Google.Protobuf/WellKnownTypes/SourceContext.cs
@@ -126,10 +126,8 @@ namespace Google.Protobuf.WellKnownTypes {
 
     public void MergeFrom(pb::CodedInputStream input) {
       uint tag;
-      while (input.ReadTag(out tag)) {
+      while ((tag = input.ReadTag()) != 0) {
         switch(tag) {
-          case 0:
-            throw pb::InvalidProtocolBufferException.InvalidTag();
           default:
             if (pb::WireFormat.IsEndGroupTag(tag)) {
               return;