I am using pi-top OS (debian stretch).
I am using an official UNO board.
I have been able to upload to the board using a different computer. I don't know about this one.
Here is verbose output:
Arduino: 1.8.6 (Linux), Board: "Arduino/Genuino Uno"
/home/pi/Documents/arduino-1.8.6/arduino-builder -dump-prefs -logger=machine -hardware /home/pi/Documents/arduino-1.8.6/hardware -hardware /home/pi/.arduino15/packages -tools /home/pi/Documents/arduino-1.8.6/tools-builder -tools /home/pi/Documents/arduino-1.8.6/hardware/tools/avr -tools /home/pi/.arduino15/packages -built-in-libraries /home/pi/Documents/arduino-1.8.6/libraries -libraries /home/pi/Arduino/libraries -fqbn=arduino:avr:uno -vid-pid=0X2A03_0X0043 -ide-version=10806 -build-path /tmp/arduino_build_916774 -warnings=default -build-cache /tmp/arduino_cache_158538 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.arduinoOTA.path=/home/pi/.arduino15/packages/arduino/tools/arduinoOTA/1.2.1 -prefs=runtime.tools.avr-gcc.path=/home/pi/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2 -prefs=runtime.tools.avrdude.path=/home/pi/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino14 -verbose /home/pi/Arduino/Installation_Sketch_Hl2/Installation_Sketch_Hl2.ino
/home/pi/Documents/arduino-1.8.6/arduino-builder -compile -logger=machine -hardware /home/pi/Documents/arduino-1.8.6/hardware -hardware /home/pi/.arduino15/packages -tools /home/pi/Documents/arduino-1.8.6/tools-builder -tools /home/pi/Documents/arduino-1.8.6/hardware/tools/avr -tools /home/pi/.arduino15/packages -built-in-libraries /home/pi/Documents/arduino-1.8.6/libraries -libraries /home/pi/Arduino/libraries -fqbn=arduino:avr:uno -vid-pid=0X2A03_0X0043 -ide-version=10806 -build-path /tmp/arduino_build_916774 -warnings=default -build-cache /tmp/arduino_cache_158538 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.arduinoOTA.path=/home/pi/.arduino15/packages/arduino/tools/arduinoOTA/1.2.1 -prefs=runtime.tools.avr-gcc.path=/home/pi/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2 -prefs=runtime.tools.avrdude.path=/home/pi/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino14 -verbose /home/pi/Arduino/Installation_Sketch_Hl2/Installation_Sketch_Hl2.ino
Using board 'uno' from platform in folder: /home/pi/.arduino15/packages/arduino/hardware/avr/1.6.23
Using core 'arduino' from platform in folder: /home/pi/.arduino15/packages/arduino/hardware/avr/1.6.23
Build options changed, rebuilding all
Detecting libraries used...
/home/pi/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10806 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR -I/home/pi/.arduino15/packages/arduino/hardware/avr/1.6.23/cores/arduino -I/home/pi/.arduino15/packages/arduino/hardware/avr/1.6.23/variants/standard /tmp/arduino_build_916774/sketch/Installation_Sketch_Hl2.ino.cpp -o /dev/null
avr-g++: error: device-specs/specs-atmega328p: No such file or directory
exit status 1
Error compiling for board Arduino/Genuino Uno.