/home/builder/opt/arduino-builder/arduino-builder -compile -core-api-version 10611 -hardware /home/builder/opt/arduino-builder/hardware -hardware /home/builder/.arduino15/packages -tools /home/builder/opt/arduino-builder/tools -tools /home/builder/.arduino15/packages -built-in-libraries /home/builder/opt/libraries/latest -logger humantags -fqbn arduino:avr:uno -build-cache /tmp -build-path /tmp/516080486/build -verbose -prefs runtime.tools.sketchUploader.path=/home/builder/.arduino15/packages/Intel/tools/sketchUploader/1.6.2+1.0 -prefs runtime.tools.CMSIS.path=/home/builder/.arduino15/packages/arduino/tools/CMSIS/4.5.0 -prefs runtime.tools.avrdude.path=/home/builder/.arduino15/packages/arduino/tools/avrdude/6.3.0-arduino14 -prefs runtime.tools.linuxuploader.path=/home/builder/.arduino15/packages/arduino/tools/linuxuploader/1.5.1 -prefs runtime.tools.nrf5x-cl-tools.path=/home/builder/.arduino15/packages/arduino/tools/nrf5x-cl-tools/9.3.1 -prefs runtime.tools.x86-linux-gcc.path=/home/builder/.arduino15/packages/arduino/tools/x86-linux-gcc/7.2.0 -prefs runtime.tools.i586-poky-linux-uclibc.path=/home/builder/.arduino15/packages/Intel/tools/i586-poky-linux-uclibc/1.6.2+1.0 -prefs runtime.tools.arm-none-eabi-gcc.path=/home/builder/.arduino15/packages/arduino/tools/arm-none-eabi-gcc/7-2017q4 -prefs runtime.tools.avr-gcc.path=/home/builder/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2 -prefs runtime.tools.CMSIS-Atmel.path=/home/builder/.arduino15/packages/arduino/tools/CMSIS-Atmel/1.2.0 -prefs runtime.tools.mkspiffs.path=/home/builder/.arduino15/packages/esp8266/tools/mkspiffs/2.5.0-3-20ed2b9 -prefs runtime.tools.arc-elf32.path=/home/builder/.arduino15/packages/Intel/tools/arc-elf32/1.6.9+1.0.1 -prefs runtime.tools.flashpack.path=/home/builder/.arduino15/packages/Intel/tools/flashpack/2.0.0 -prefs runtime.tools.arduinoOTA.path=/home/builder/.arduino15/packages/arduino/tools/arduinoOTA/1.2.1 -prefs runtime.tools.dfu-util.path=/home/builder/.arduino15/packages/arduino/tools/dfu-util/0.9.0-arduino1 -prefs runtime.tools.arm-linux-gcc.path=/home/builder/.arduino15/packages/arduino/tools/arm-linux-gcc/4.9.3 -prefs runtime.tools.xtensa-lx106-elf-gcc.path=/home/builder/.arduino15/packages/esp8266/tools/xtensa-lx106-elf-gcc/2.5.0-3-20ed2b9 -prefs runtime.tools.esptool.path=/home/builder/.arduino15/packages/esp8266/tools/esptool/2.5.0-3-20ed2b9 -prefs runtime.tools.core2-32-poky-linux.path=/home/builder/.arduino15/packages/Intel/tools/core2-32-poky-linux/1.6.2+1.0 -prefs runtime.tools.openocd.path=/home/builder/.arduino15/packages/Intel/tools/openocd/0.9.0+0.1 -prefs runtime.tools.bossac.path=/home/builder/.arduino15/packages/industruino/tools/bossac/1.7.0-industruino -prefs runtime.tools.arduino101load.path=/home/builder/.arduino15/packages/Intel/tools/arduino101load/2.0.1 -libraries /tmp/516080486/custom -libraries /tmp/516080486/pinned /tmp/516080486/Blink
Using board 'uno' from platform in folder: /home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23
Using core 'arduino' from platform in folder: /home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23
Detecting libraries used...
/home/builder/.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=10611 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/cores/arduino -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/variants/standard /tmp/516080486/build/sketch/Blink.ino.cpp -o /dev/null
Generating function prototypes...
/home/builder/.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=10611 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/cores/arduino -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/variants/standard /tmp/516080486/build/sketch/Blink.ino.cpp -o /tmp/516080486/build/preproc/ctags_target_for_gcc_minus_e.cpp
/home/builder/opt/arduino-builder/tools/ctags/5.8-arduino11/ctags -u --language-force=c++ -f - --c++-kinds=svpf --fields=KSTtzns --line-directives /tmp/516080486/build/preproc/ctags_target_for_gcc_minus_e.cpp
Compiling sketch...
/home/builder/.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 -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10611 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/cores/arduino -I/home/builder/.arduino15/packages/arduino/hardware/avr/1.6.23/variants/standard /tmp/516080486/build/sketch/Blink.ino.cpp -o /tmp/516080486/build/sketch/Blink.ino.cpp.o
Compiling libraries...
Compiling core...
Using precompiled core: /tmp/core/core_arduino_avr_uno_f73f8035d4928006c181f54a2aa5f0b0.a
Linking everything together...
/home/builder/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2/bin/avr-gcc -w -Os -g -flto -fuse-linker-plugin -Wl,--gc-sections -mmcu=atmega328p -o /tmp/516080486/build/Blink.ino.elf /tmp/516080486/build/sketch/Blink.ino.cpp.o /tmp/516080486/build/../../core/core_arduino_avr_uno_f73f8035d4928006c181f54a2aa5f0b0.a -L/tmp/516080486/build -lm
/home/builder/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2/bin/avr-objcopy -O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 /tmp/516080486/build/Blink.ino.elf /tmp/516080486/build/Blink.ino.eep
/home/builder/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2/bin/avr-objcopy -O ihex -R .eeprom /tmp/516080486/build/Blink.ino.elf /tmp/516080486/build/Blink.ino.hex
/home/builder/.arduino15/packages/arduino/tools/avr-gcc/5.4.0-atmel3.6.1-arduino2/bin/avr-size -A /tmp/516080486/build/Blink.ino.elf
Sketch uses 930 bytes (2%) of program storage space. Maximum is 32256 bytes.
Global variables use 9 bytes (0%) of dynamic memory, leaving 2039 bytes for local variables. Maximum is 2048 bytes.
Programming with: Serial
Flashing with command:C:/Users/Giovanni/.arduino-create/arduino/avrdude/6.3.0-arduino14/bin/avrdude.exe -CC:/Users/Giovanni/.arduino-create/arduino/avrdude/6.3.0-arduino14/etc/avrdude.conf -v -patmega328p -carduino -PCOM3 -b115200 -D -Uflash:w:C:/Users/Giovanni/AppData/Local/Temp/arduino-create-agent919570391/Blink.hex:i
avrdude: Version 6.3-20171130
Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
Copyright (c) 2007-2014 Joerg Wunsch
System wide configuration file is "C:/Users/Giovanni/.arduino-create/arduino/avrdude/6.3.0-arduino14/etc/avrdude.conf"
Using Port : COM3
Using Programmer : arduino
Overriding Baud Rate : 115200
avrdude: ser_open(): can't open device "\\.\COM3": Impossibile trovare il file specificato.
avrdude done. Thank you.
Buonasera,
essendo il tuo primo post, nel rispetto del regolamento della sezione Italiana del forum (… punto 13, primo capoverso), ti chiedo cortesemente di presentarti IN QUESTO THREAD (spiegando bene quali conoscenze hai di elettronica e di programmazione ... possibilmente evitando di scrivere solo una riga di saluto) e di leggere con molta attenzione tutto il su citato REGOLAMENTO ... Grazie. 
Guglielmo
P.S.: Ti ricordo che, purtroppo, fino a quando non sarà fatta la presentazione nell’apposito thread, nessuno ti potrà rispondere, quindi ti consiglio di farla al più presto. 
P.P.S.: Se poi spieghi anche esattamente quali sono tutte le "condizioni al contorno" invece di mettere solo i messaggi di avrdude ... magari ti si può aiutare.