# fatal error when compiling

**URL:** <https://forum.arduino.cc/t/fatal-error-when-compiling/630998>\
**Category:** Cloud Editor\
**Created:** [January 13, 2020, 9:55pm UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998 "2020-01-13T21:55:10Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![aams86](https://avatars.discourse-cdn.com/v4/letter/a/f0a364/32.png) [@aams86](https://forum.arduino.cc/u/aams86)\
**Post date:** [January 13, 2020, 9:55pm UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998/1 "2020-01-13T21:55:10Z")

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Hi, I am starting a new topic here because it appears I am not the only one experiencing this issue, but it is getting posted to an old thread. I have two robotics classes that have been using the web editor, and today all of the students are getting the same error when trying to compile:

They are working on laptops with Windows 10, and primarily using the chrome browser.

```cpp
lto1: fatal error: bytecode stream in file '/tmp/066488613/build/../../core/core_arduino_avr_uno_0fd389f0184d5a21fcc443ff311da7f1.a' generated with LTO version 4.1 instead of the expected 6.0

compilation terminated.

lto-wrapper: fatal error: /home/builder/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino5/bin/avr-gcc returned 1 exit status

compilation terminated.

/home/builder/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino5/bin/../lib/gcc/avr/7.3.0/../../../../avr/bin/ld: error: lto-wrapper failed

collect2: error: ld returned 1 exit status

exit status 1

```

Is there anything we can do on our end to solve this problem?

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**Author:** ![kflanaryolayvar](https://avatars.discourse-cdn.com/v4/letter/k/bbe5ce/32.png) [@kflanaryolayvar](https://forum.arduino.cc/u/kflanaryolayvar)\
**Post date:** [January 14, 2020, 1:37am UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998/2 "2020-01-14T01:37:08Z")

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My whole class was getting this error today too. We had no problems last week.

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**Author:** ![mpwteach](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/mpwteach/32/325905_2.png) [@mpwteach](https://forum.arduino.cc/u/mpwteach)\
**Post date:** [January 14, 2020, 3:51am UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998/3 "2020-01-14T03:51:35Z")

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I have the same issue. 80+ students disrupted and put out of action today! Please fix ASAP.

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**Author:** ![Ballscrewbob](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/ballscrewbob/32/950458_2.png) [@Ballscrewbob](https://forum.arduino.cc/u/Ballscrewbob)\
**Post date:** [January 14, 2020, 12:43pm UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998/4 "2020-01-14T12:43:55Z")

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According to the team it was fixed.  
Thanks for your reports.

Bob.

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**Author:** ![system](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/system/32/1140315_2.png) [@system](https://forum.arduino.cc/u/system)\
**Post date:** [May 7, 2021, 11:50am UTC](https://forum.arduino.cc/t/fatal-error-when-compiling/630998/5 "2021-05-07T11:50:50Z")

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Closed on May 7, 2021, 11:50am UTC