avr-g++ (or avr-gcc) and LiquidCrystal library

Question

I'm trying to run a simple Hello World program from Arduino 1.6.5 from terminal. When I run it in Arduino IDE, it works good. When I'm trying to get it by avr-g++ I have hard way to figure out how to include all libraries - so far I got this script:

avr-g++ -Os -DF_CPU=16000000UL -mmcu=atmega328p -c -o main.o main.cpp 
-I"../arduino-1.6.5-r5/libraries/LiquidCrystal/src/"
-I"../arduino-1.6.5-r5/hardware/arduino/avr/cores/arduino/"
avr-g++ -mmcu=atmega328p main.o -o main
avr-objcopy -O ihex -R .eeprom main main.hex
sudo avrdude -F -V -c arduino -p ATMEGA328P -P /dev/ttyACM1 -b 115200 -U flash:w:main.hex

First line (with both -I flags) compiles, but after running second line, I get:

main.o: In function `main':
main.cpp:(.text.startup+0xa): undefined reference to `LiquidCrystal::begin(unsigned char, unsigned char, unsigned char)'
main.cpp:(.text.startup+0x16): undefined reference to `Print::print(char const*)'
main.o: In function `_GLOBAL__sub_I_lcd':
main.cpp:(.text.startup+0x3a): undefined reference to `LiquidCrystal::LiquidCrystal(unsigned char, unsigned char, unsigned char, unsigned char, unsigned char, unsigned char)'
collect2: error: ld returned 1 exit status

How can I also include some libraries? I need the exact bash script.

• Ignacio Vazquez-Abrams: Have you tried duplicating every nitty little step the IDE goes through.
• Cheshire Cat: I don't know how, though.
• Ignacio Vazquez-Abrams: possible duplicate of not using the IDE and understanding the compilation/linking/upload process

Answer 1

I made a Makefile to compile the Blink program a little while back. It wasn't trivial.

#
# Simple Arduino Makefile
#
# Author: Nick Gammon
# Date: 18th March 2015
# where you installed the Arduino app
ARDUINO_DIR = C:/Documents and Settings/Nick/Desktop/arduino-1.0.6/
# various programs
CC = "$(ARDUINO_DIR)hardware/tools/avr/bin/avr-gcc"
CPP = "$(ARDUINO_DIR)hardware/tools/avr/bin/avr-g++"
AR = "$(ARDUINO_DIR)hardware/tools/avr/bin/avr-ar"
OBJ_COPY = "$(ARDUINO_DIR)hardware/tools/avr/bin/avr-objcopy"
MAIN_SKETCH = Blink.cpp
# compile flags for g++ and gcc
# may need to change these
F_CPU = 16000000
MCU = atmega328p
# compile flags
GENERAL_FLAGS = -c -g -Os -Wall -ffunction-sections -fdata-sections -mmcu=$(MCU) -DF_CPU=$(F_CPU)L -MMD -DUSB_VID=null -DUSB_PID=null -DARDUINO=106
CPP_FLAGS = $(GENERAL_FLAGS) -fno-exceptions
CC_FLAGS = $(GENERAL_FLAGS)
# location of include files
INCLUDE_FILES = "-I$(ARDUINO_DIR)hardware/arduino/cores/arduino" "-I$(ARDUINO_DIR)hardware/arduino/variants/standard"
# library sources
LIBRARY_DIR = "$(ARDUINO_DIR)hardware/arduino/cores/arduino/"
build:
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(MAIN_SKETCH) -o $(MAIN_SKETCH).o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)avr-libc/malloc.c -o malloc.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)avr-libc/realloc.c -o realloc.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)WInterrupts.c -o WInterrupts.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)wiring.c -o wiring.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)wiring_analog.c -o wiring_analog.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)wiring_digital.c -o wiring_digital.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)wiring_pulse.c -o wiring_pulse.c.o
 $(CC) $(CC_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)wiring_shift.c -o wiring_shift.c.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)CDC.cpp -o CDC.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)HardwareSerial.cpp -o HardwareSerial.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)HID.cpp -o HID.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)IPAddress.cpp -o IPAddress.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)main.cpp -o main.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)new.cpp -o new.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)Print.cpp -o Print.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)Stream.cpp -o Stream.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)Tone.cpp -o Tone.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)USBCore.cpp -o USBCore.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)WMath.cpp -o WMath.cpp.o
 $(CPP) $(CPP_FLAGS) $(INCLUDE_FILES) $(LIBRARY_DIR)WString.cpp -o WString.cpp.o
 rm core.a
 $(AR) rcs core.a malloc.c.o
 $(AR) rcs core.a realloc.c.o
 $(AR) rcs core.a WInterrupts.c.o
 $(AR) rcs core.a wiring.c.o
 $(AR) rcs core.a wiring_analog.c.o
 $(AR) rcs core.a wiring_digital.c.o
 $(AR) rcs core.a wiring_pulse.c.o
 $(AR) rcs core.a wiring_shift.c.o
 $(AR) rcs core.a CDC.cpp.o
 $(AR) rcs core.a HardwareSerial.cpp.o
 $(AR) rcs core.a HID.cpp.o
 $(AR) rcs core.a IPAddress.cpp.o
 $(AR) rcs core.a main.cpp.o
 $(AR) rcs core.a new.cpp.o
 $(AR) rcs core.a Print.cpp.o
 $(AR) rcs core.a Stream.cpp.o
 $(AR) rcs core.a Tone.cpp.o
 $(AR) rcs core.a USBCore.cpp.o
 $(AR) rcs core.a WMath.cpp.o
 $(AR) rcs core.a WString.cpp.o
 $(CC) -Os -Wl,--gc-sections -mmcu=$(MCU) -o $(MAIN_SKETCH).elf $(MAIN_SKETCH).o core.a -lm
 $(OBJ_COPY) -O ihex -j .eeprom --set-section-flags=.eeprom=alloc,load --no-change-warnings --change-section-lma .eeprom=0 $(MAIN_SKETCH).elf $(MAIN_SKETCH).eep
 $(OBJ_COPY) -O ihex -R .eeprom $(MAIN_SKETCH).elf $(MAIN_SKETCH).hex

---

I basically did this by observing what the IDE does (as Ignacio Vazquez-Abrams suggested) and replicated it. Now to add libraries you have to add even more steps.

• Cheshire Cat: It doesn't work well for me, even if i change everything. Linux can't find malloc.c in files.
• Nick Gammon: You must be able to find them, as Ignacio Vazquez-Abrams suggested. Turn on verbose compiling, do a compile, and see where the IDE finds them.
• Cheshire Cat: Ok, I found them. Thanks. I'll post tomorrow results.