Prototype Generation With Typedef'd Types

[zachdeibert]

When the Arduino IDE attempts to generate the prototypes for a function where the types that are a part of that prototype are defined in a header file, the IDE does not always include the header file defining the type before the generated prototype is emitted to the file that is passed into G++.

(Code is available for download here)

arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino

void setup() {
  Serial.begin(115200);
}

void loop() {
  Serial.print("2 + 2 = ");
  Serial.println(add(2, 2));
  delay(1000);
}

arduino-ide-prototype-bug/add.ino

#include "number.h"

number_t add(number_t a, number_t b) {
  return a + b;
}

arduino-ide-prototype-bug/number.h

typedef int number_t;

Build Output:

/home/zach/software/arduino-1.8.5/arduino-builder -dump-prefs -logger=machine -hardware /home/zach/software/arduino-1.8.5/hardware -tools /home/zach/software/arduino-1.8.5/tools-builder -tools /home/zach/software/arduino-1.8.5/hardware/tools/avr -built-in-libraries /home/zach/software/arduino-1.8.5/libraries -libraries /home/zach/Arduino/libraries -fqbn=arduino:avr:nano:cpu=atmega328 -ide-version=10805 -build-path /tmp/arduino_build_613863 -warnings=all -build-cache /tmp/arduino_cache_167137 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.avrdude.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -prefs=runtime.tools.arduinoOTA.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -prefs=runtime.tools.avr-gcc.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -verbose /code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino
/home/zach/software/arduino-1.8.5/arduino-builder -compile -logger=machine -hardware /home/zach/software/arduino-1.8.5/hardware -tools /home/zach/software/arduino-1.8.5/tools-builder -tools /home/zach/software/arduino-1.8.5/hardware/tools/avr -built-in-libraries /home/zach/software/arduino-1.8.5/libraries -libraries /home/zach/Arduino/libraries -fqbn=arduino:avr:nano:cpu=atmega328 -ide-version=10805 -build-path /tmp/arduino_build_613863 -warnings=all -build-cache /tmp/arduino_cache_167137 -prefs=build.warn_data_percentage=75 -prefs=runtime.tools.avrdude.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -prefs=runtime.tools.arduinoOTA.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -prefs=runtime.tools.avr-gcc.path=/home/zach/software/arduino-1.8.5/hardware/tools/avr -verbose /code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino
Using board 'nano' from platform in folder: /home/zach/software/arduino-1.8.5/hardware/arduino/avr
Using core 'arduino' from platform in folder: /home/zach/software/arduino-1.8.5/hardware/arduino/avr
Detecting libraries used...
"/home/zach/software/arduino-1.8.5/hardware/tools/avr/bin/avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics  -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10805 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR   "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/cores/arduino" "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/variants/eightanaloginputs" "/tmp/arduino_build_613863/sketch/arduino-ide-prototype-bug.ino.cpp" -o "/dev/null"
Generating function prototypes...
"/home/zach/software/arduino-1.8.5/hardware/tools/avr/bin/avr-g++" -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics  -flto -w -x c++ -E -CC -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10805 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR   "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/cores/arduino" "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/variants/eightanaloginputs" "/tmp/arduino_build_613863/sketch/arduino-ide-prototype-bug.ino.cpp" -o "/tmp/arduino_build_613863/preproc/ctags_target_for_gcc_minus_e.cpp"
"/home/zach/software/arduino-1.8.5/tools-builder/ctags/5.8-arduino11/ctags" -u --language-force=c++ -f - --c++-kinds=svpf --fields=KSTtzns --line-directives "/tmp/arduino_build_613863/preproc/ctags_target_for_gcc_minus_e.cpp"
Compiling sketch...
"/home/zach/software/arduino-1.8.5/hardware/tools/avr/bin/avr-g++" -c -g -Os -Wall -Wextra -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -MMD -flto -mmcu=atmega328p -DF_CPU=16000000L -DARDUINO=10805 -DARDUINO_AVR_NANO -DARDUINO_ARCH_AVR   "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/cores/arduino" "-I/home/zach/software/arduino-1.8.5/hardware/arduino/avr/variants/eightanaloginputs" "/tmp/arduino_build_613863/sketch/arduino-ide-prototype-bug.ino.cpp" -o "/tmp/arduino_build_613863/sketch/arduino-ide-prototype-bug.ino.cpp.o"
add:3: error: 'number_t' does not name a type
 number_t add(number_t a, number_t b) {
 ^
/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino: In function 'void loop()':
arduino-ide-prototype-bug:7: error: 'add' was not declared in this scope
   Serial.println(add(2, 2));
                          ^
exit status 1
'number_t' does not name a type

C++ file generation:

#include <Arduino.h>
#line 1 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino"
#line 1 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino"
#line 1 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino"
void setup();
#line 5 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino"
void loop();
#line 3 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/add.ino"
number_t add(number_t a, number_t b);
#line 1 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/arduino-ide-prototype-bug.ino"
void setup() {
  Serial.begin(115200);
}

void loop() {
  Serial.print("2 + 2 = ");
  Serial.println(add(2, 2));
  delay(1000);
}


#line 1 "/code/github.com/zachdeibert/arduino-ide-prototype-bug/add.ino"
#include "number.h"

number_t add(number_t a, number_t b) {
  return a + b;
}

Workaround: Including all header files into the main INO fixes the problem, but that should not be required.

(originally at arduino/Arduino#8050)