Open
Description
Describe the request
If a sketch is recompiled twice in a row, the Arduino-preprocessed sketch Sketch.ino.cpp is recompiled and re-linked even if not necessary.
Describe the current behavior
If you do the same compile twice in a row:
~/Arduino/Blink$ LANG=en arduino-cli compile -b arduino:avr:uno --clean
Sketch uses 1636 bytes (5%) of program storage space. Maximum is 32256 bytes.
Global variables use 122 bytes (5%) of dynamic memory, leaving 1926 bytes for local variables. Maximum is 2048 bytes.
Used library Version Path
Wire 1.0 /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/libraries/Wire
Used platform Version Path
arduino:avr 1.8.6 /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6
~/Arduino/Blink$ LANG=en arduino-cli compile -b arduino:avr:uno -v
FQBN: arduino:avr:uno
Using board 'uno' from platform in folder: /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6
Using core 'arduino' from platform in folder: /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6
Detecting libraries used...
[...]
Generating function prototypes...
[...]
Compiling sketch...
/home/megabug/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/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=10607 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR -I/home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/cores/arduino -I/home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/variants/standard -I/home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/libraries/Wire/src /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/sketch/Blink.ino.cpp -o /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/sketch/Blink.ino.cpp.o
Compiling libraries...
Compiling library "Wire"
Using previously compiled file: /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/libraries/Wire/utility/twi.c.o
Using previously compiled file: /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/libraries/Wire/Wire.cpp.o
Compiling core...
Using precompiled core: /tmp/arduino/cores/arduino_avr_uno_12e4cfbdc0590d50ab9cd20e50a4c3c5/core.a
Linking everything together...
/home/megabug/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-gcc -w -Os -g -flto -fuse-linker-plugin -Wl,--gc-sections -mmcu=atmega328p -o /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.elf /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/sketch/Blink.ino.cpp.o /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/libraries/Wire/Wire.cpp.o /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/libraries/Wire/utility/twi.c.o /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/../../cores/arduino_avr_uno_12e4cfbdc0590d50ab9cd20e50a4c3c5/core.a -L/tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3 -lm
/home/megabug/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-objcopy -O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.elf /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.eep
/home/megabug/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-objcopy -O ihex -R .eeprom /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.elf /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.hex
Multiple libraries were found for "Wire.h"
Used: /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/libraries/Wire
Not used: /home/megabug/Workspace/Arduino_Threads
Using library Wire at version 1.0 in folder: /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/libraries/Wire
/home/megabug/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino7/bin/avr-size -A /tmp/arduino/sketches/002050EAA7EFB9A4FC451CDFBC0FA2D3/Blink.ino.elf
Sketch uses 1636 bytes (5%) of program storage space. Maximum is 32256 bytes.
Global variables use 122 bytes (5%) of dynamic memory, leaving 1926 bytes for local variables. Maximum is 2048 bytes.
Used library Version Path
Wire 1.0 /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6/libraries/Wire
Used platform Version Path
arduino:avr 1.8.6 /home/megabug/.arduino15/packages/arduino/hardware/avr/1.8.6
🐛 The sketch file Blink.ino.cpp is recompiled even if there are no changes.
The sketch and linking phase could be completely skipped in this particular case.
Arduino CLI version
nightly
Operating system
N/A
Operating system version
N/A
Additional context
Related to #1996
Issue checklist
- I searched for previous requests in the issue tracker
- I verified the feature was still missing when using the nightly build
- My request contains all necessary details