Extending vocabulary by a large size crashes RobertaTokenizerFast
# 🐛 Bug

## Information

Model I am using: RoBERTa

Language I am using the model on: English

The problem arises when using:
* [ ] the official example scripts: (give details below)
* [x] my own modified scripts: (give details below)

The tasks I am working on is:
* [ ] an official GLUE/SQUaD task: (give the name)
* [x] my own task or dataset: (give details below)

## To reproduce

Steps to reproduce the behavior:

```python
from transformers import RobertaTokenizerFast

tokenizer = RobertaTokenizerFast.from_pretrained('roberta-base')
tokenizer.add_tokens([str(i) for i in range(60000)])
```

Here's the stack trace:
```
thread '<unnamed>' panicked at 'called `Result::unwrap()` on an `Err` value: CompiledTooBig(10485760)', /__w/tokenizers/tokenizers/tokenizers/src/tokenizer/added_vocabulary.rs:299:13
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/libunwind.rs:86
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.46/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:78
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1069
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1537
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:198
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:218
  10: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:477
  11: rust_begin_unwind
             at src/libstd/panicking.rs:385
  12: core::panicking::panic_fmt
             at src/libcore/panicking.rs:89
  13: core::option::expect_none_failed
             at src/libcore/option.rs:1272
  14: tokenizers::tokenizer::added_vocabulary::AddedVocabulary::add_tokens
  15: tokenizers::tokenizer::Tokenizer::add_tokens
  16: tokenizers::tokenizer::__init11742626496714830824::__init11742626496714830824::__wrap
  17: method_vectorcall_VARARGS_KEYWORDS
             at /tmp/build/80754af9/python_1593706424329/work/Objects/descrobject.c:332
  18: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  19: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  20: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  21: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  22: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  23: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  24: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  25: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  26: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
  27: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
  28: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  29: method_vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/classobject.c:60
  30: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  31: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  32: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3515
  33: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
  34: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
  35: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  36: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  37: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  38: gen_send_ex
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:222
  39: _PyGen_Send
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:292
  40: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:2053
  41: gen_send_ex
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:222
  42: _PyGen_Send
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:292
  43: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:2053
  44: gen_send_ex
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:222
  45: _PyGen_Send
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:292
  46: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:2053
  47: gen_send_ex
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:222
  48: _PyGen_Send
             at /tmp/build/80754af9/python_1593706424329/work/Objects/genobject.c:292
  49: task_step_impl
             at /usr/local/src/conda/python-3.8.3/Modules/_asynciomodule.c:2638
  50: task_step
             at /usr/local/src/conda/python-3.8.3/Modules/_asynciomodule.c:2931
  51: _PyObject_MakeTpCall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:159
  52: context_run
             at /tmp/build/80754af9/python_1593706424329/work/Python/context.c:634
  53: cfunction_vectorcall_FASTCALL_KEYWORDS
             at /tmp/build/80754af9/python_1593706424329/work/Objects/methodobject.c:437
  54: PyVectorcall_Call
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:199
  55: do_call_core
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4983
  56: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3559
  57: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  58: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  59: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  60: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  61: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  62: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  63: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  64: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  65: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  66: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  67: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  68: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  69: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  70: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  71: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  72: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  73: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  74: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  75: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  76: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  77: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  78: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  79: _PyObject_FastCallDict
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:96
  80: _PyObject_Call_Prepend
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:887
  81: slot_tp_call
             at /tmp/build/80754af9/python_1593706424329/work/Objects/typeobject.c:6521
  82: _PyObject_MakeTpCall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:159
  83: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:125
  84: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  85: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3500
  86: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
  87: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
  88: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  89: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  90: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
  91: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
  92: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
  93: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  94: method_vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/classobject.c:60
  95: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
  96: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
  97: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3515
  98: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
  99: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
 100: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
 101: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
 102: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
 103: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
 104: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
 105: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
 106: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
 107: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
 108: function_code_fastcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:283
 109: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:410
 110: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
 111: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
 112: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3486
 113: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
 114: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
 115: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
 116: method_vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/classobject.c:89
 117: PyVectorcall_Call
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:199
 118: do_call_core
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:5010
 119: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3559
 120: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
 121: _PyFunction_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Objects/call.c:435
 122: _PyObject_Vectorcall
             at /tmp/build/80754af9/python_1593706424329/work/Include/cpython/abstract.h:127
 123: call_function
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4963
 124: _PyEval_EvalFrameDefault
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:3500
 125: _PyEval_EvalCodeWithName
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4298
 126: PyEval_EvalCodeEx
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:4327
 127: PyEval_EvalCode
             at /tmp/build/80754af9/python_1593706424329/work/Python/ceval.c:718
 128: run_eval_code_obj
             at /tmp/build/80754af9/python_1593706424329/work/Python/pythonrun.c:1125
 129: run_mod
             at /tmp/build/80754af9/python_1593706424329/work/Python/pythonrun.c:1147
 130: PyRun_FileExFlags
             at /tmp/build/80754af9/python_1593706424329/work/Python/pythonrun.c:1063
 131: PyRun_SimpleFileExFlags
             at /tmp/build/80754af9/python_1593706424329/work/Python/pythonrun.c:428
 132: pymain_run_file
             at /tmp/build/80754af9/python_1593706424329/work/Modules/main.c:387
 133: pymain_run_python
             at /tmp/build/80754af9/python_1593706424329/work/Modules/main.c:571
 134: Py_RunMain
             at /tmp/build/80754af9/python_1593706424329/work/Modules/main.c:650
 135: Py_BytesMain
             at /tmp/build/80754af9/python_1593706424329/work/Modules/main.c:1096
 136: __libc_start_main
 137: <unknown>
             at ../sysdeps/x86_64/elf/start.S:103
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
fatal runtime error: failed to initiate panic, error 5
Aborted (core dumped
```
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## Expected behavior
Tokens should get added normally

## Environment info
<!-- You can run the command `transformers-cli env` and copy-and-paste its output below.
     Don't forget to fill out the missing fields in that output! -->
     
- `transformers` version: 3.0.2
- Platform: Linux-5.3.0-1032-azure-x86_64-with-glibc2.10
- Python version: 3.8.3
- PyTorch version (GPU?): 1.5.1 (True)
- Tensorflow version (GPU?): not installed (NA)
- Using GPU in script?: No
- Using distributed or parallel set-up in script?: No

I tried using BertTokenizerFast but the problem persists.<|||||>This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.
<|||||>Is there any update on the issue? 
I have the same problem...<|||||>Also having the same problem while using `tokenizer.add_tokens` with a `unique_list` that holds the words I am trying to add to my tokenizer.<|||||>I also have this issue. <|||||>same issue