Bogoduino

A few h/cpp files to aid testing Arduino/ESP8266 code on different platforms.

Usage

Check out this code in the ./bogoduino directory:

git submodule add https://github.com/wdoekes/bogoduino.git

Add -I./bogoduino subdirectory to the CPPFLAGS:

CPPFLAGS = -DTEST_BUILD -g -I./bogoduino

Tips for compiler warnings

As always, compiler warnings are generally useful. However, the Arduino IDE does a job of hiding them. This may lead you to create code like:

int value = 123456;

And that code will run fine on your Intel or Xtensa (ESP8266). But it would get truncated on the AVR (Atmel, Arduino) which has 16 bit integers.

To remedy this, you can enable warnings:

• There are predefined values for the compiler flags. You can find them in a file similar to hardware/arduino/avr/platform.txt (exact location on your system may differ):

  $ grep ^compiler.warning_flags /snap/arduino/current/hardware/arduino/avr/platform.txt
  compiler.warning_flags=-w
  compiler.warning_flags.none=-w
  compiler.warning_flags.default=
  compiler.warning_flags.more=-Wall
  compiler.warning_flags.all=-Wall -Wextra
  

• Exit the Arduino IDE and look for a file called preferences.txt (again, the file may be elsewhere on your system):

  $ grep ^compiler.warning ~/snap/arduino/current/.arduino15/preferences.txt
  compiler.warning_level=none
  

  Edit it so it says: compiler.warning_level=all

• Start the Arduino IDE and go to File -> Preferences -> Settings to find a checkbox called "Show verbose output during compilation". Check it.

Now, when compiling, you'll get a whole bunch more output. But also things like:

/snap/arduino/50/hardware/tools/avr/bin/avr-g++ -c -g -Os -Wall
  -Wextra -std=gnu++11 -fpermissive -fno-exceptions
  -ffunction-sections -fdata-sections -fno-threadsafe-statics
  -Wno-error=narrowing -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L
  -DARDUINO=10813 -DARDUINO_AVR_UNO -DARDUINO_ARCH_AVR
  -I/snap/arduino/50/hardware/arduino/avr/cores/arduino
  -I/snap/arduino/50/hardware/arduino/avr/variants/standard
  /tmp/arduino_build_940516/sketch/int_size_test.ino.cpp -o
  /tmp/arduino_build_940516/sketch/int_size_test.ino.cpp.o
~/Arduino/proj/int_size_test/int_size_test.ino:1:13:
  warning: overflow in implicit constant conversion [-Woverflow]
 int value = 123456;
             ^~~~~~

Better!