private static int WriteCodeViewData(BlobBuilder builder, string pdbPath, Guid pdbGuid)
        {
            int start = builder.Count;

            builder.WriteByte((byte)'R');
            builder.WriteByte((byte)'S');
            builder.WriteByte((byte)'D');
            builder.WriteByte((byte)'S');

            // PDB id:
            builder.WriteGuid(pdbGuid);

            // age
            builder.WriteUInt32(1);

            // UTF-8 encoded zero-terminated path to PDB
            int pathStart = builder.Count;
            builder.WriteUTF8(pdbPath, allowUnpairedSurrogates: true);
            builder.WriteByte(0);

            return builder.Count - start;
        }