1 files changed, 4 insertions, 75 deletions

diff --git a/src/mscorlib/shared/System/Text/UTF8Encoding.cs b/src/mscorlib/shared/System/Text/UTF8Encoding.cs
index 5cfa89018a..ee5c92c3a8 100644
--- a/src/mscorlib/shared/System/Text/UTF8Encoding.cs
+++ b/src/mscorlib/shared/System/Text/UTF8Encoding.cs
@@ -34,7 +34,6 @@ namespace System.Text
     // used mostly to distinguish UTF-8 text from other encodings, and doesn't
     // switch the byte orderings.
 
-    [Serializable]
     public class UTF8Encoding : Encoding
     {
         /*
@@ -53,7 +52,6 @@ namespace System.Text
         private const int UTF8_CODEPAGE = 65001;
 
         // Allow for devirtualization (see https://github.com/dotnet/coreclr/pull/9230)
-        [Serializable]
         internal sealed class UTF8EncodingSealed : UTF8Encoding
         {
             public UTF8EncodingSealed(bool encoderShouldEmitUTF8Identifier) : base(encoderShouldEmitUTF8Identifier) { }
@@ -2521,7 +2519,6 @@ namespace System.Text
                    UTF8_CODEPAGE + (_emitUTF8Identifier ? 1 : 0);
         }
 
-        [Serializable]
         private sealed class UTF8Encoder : EncoderNLS, ISerializable
         {
             // We must save a high surrogate value until the next call, looking
@@ -2533,46 +2530,10 @@ namespace System.Text
                 // base calls reset
             }
 
-            // Constructor called by serialization, have to handle deserializing from Everett
-            internal UTF8Encoder(SerializationInfo info, StreamingContext context)
-            {
-                // Any info?
-                if (info == null) throw new ArgumentNullException(nameof(info));
-                Contract.EndContractBlock();
-
-                // Get common info
-                this.m_encoding = (Encoding)info.GetValue("encoding", typeof(Encoding));
-
-                // SurrogateChar happens to mean the same thing
-                this.surrogateChar = (int)info.GetValue("surrogateChar", typeof(int));
-
-                try
-                {
-                    this.m_fallback = (EncoderFallback)info.GetValue("m_fallback", typeof(EncoderFallback));
-                }
-                catch (SerializationException)
-                {
-                    this.m_fallback = null;
-                }
-            }
-
-            // ISerializable implementation, get data for this object
+            // ISerializable implementation
             void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
             {
-                // Any info?
-                if (info == null) throw new ArgumentNullException(nameof(info));
-                Contract.EndContractBlock();
-
-                // Save Whidbey data
-                // Just need Everett maxCharSize (BaseCodePageEncoding) or m_maxByteSize (MLangBaseCodePageEncoding)
-                info.AddValue("encoding", this.m_encoding);
-                info.AddValue("surrogateChar", this.surrogateChar);
-
-                info.AddValue("m_fallback", this.m_fallback);
-
-                // Extra stuff for Everett that Whidbey doesn't use
-                info.AddValue("storedSurrogate", this.surrogateChar > 0 ? true : false);
-                info.AddValue("mustFlush", false);  // Everett doesn't actually use this either, but it accidently serialized it!
+                throw new PlatformNotSupportedException();
             }
 
             public override void Reset()
@@ -2593,7 +2554,6 @@ namespace System.Text
             }
         }
 
-        [Serializable]
         private sealed class UTF8Decoder : DecoderNLS, ISerializable
         {
             // We'll need to remember the previous information. See the comments around definition
@@ -2608,44 +2568,13 @@ namespace System.Text
             // Constructor called by serialization, have to handle deserializing from Everett
             internal UTF8Decoder(SerializationInfo info, StreamingContext context)
             {
-                // Any info?
-                if (info == null) throw new ArgumentNullException(nameof(info));
-                Contract.EndContractBlock();
-
-                // Get common info
-                this.m_encoding = (Encoding)info.GetValue("encoding", typeof(Encoding));
-
-                try
-                {
-                    // Get whidbey version of bits
-                    this.bits = (int)info.GetValue("wbits", typeof(int));
-                    this.m_fallback = (DecoderFallback)info.GetValue("m_fallback", typeof(DecoderFallback));
-                }
-                catch (SerializationException)
-                {
-                    // Everett calls bits bits instead of wbits, so this is Everett
-                    this.bits = 0;
-                    this.m_fallback = null;
-                }
+                throw new PlatformNotSupportedException();
             }
 
             // ISerializable implementation, get data for this object
             void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
             {
-                // Any info?
-                if (info == null) throw new ArgumentNullException(nameof(info));
-                Contract.EndContractBlock();
-
-                // Save new Whidbey data
-                info.AddValue("encoding", this.m_encoding);
-                info.AddValue("wbits", this.bits);          // Special whidbey bits name
-                info.AddValue("m_fallback", this.m_fallback);
-
-                // Everett has extra stuff, we set it all to 0 in case this deserializes in Everett
-                info.AddValue("bits", (int)0);
-                info.AddValue("trailCount", (int)0);
-                info.AddValue("isSurrogate", false);
-                info.AddValue("byteSequence", (int)0);
+                throw new PlatformNotSupportedException();
             }
 
             public override void Reset()