#if bug

[lestofante]

#ifdef __AVR_ATtinyX5__
const byte LED_PIN = 3;   // gamba 2
const byte RECV_PIN = 1;  // gamba 6
#else
const byte LED_PIN = 3;
const byte RECV_PIN = 10;
#endif

give error. declaring a variable before #if resolve the problem.

bug found by nid69ita

[matthijskooijman]

What kind of error does this give? The code looks good to me?

[lestofante]

just copy-paste the following code to the ide

#ifdef __AVR_ATtinyX5__
const byte LED_PIN = 3;   // gamba 2
const byte RECV_PIN = 1;  // gamba 6
#else
const byte LED_PIN = 3;
const byte RECV_PIN = 10;
#endif

void setup(){
}

void loop(){
}

compile for any board and you'll get (also tryed with uint8_t):

sketch_jun13a:4: error: 'byte' does not name a type
sketch_jun13a:5: error: 'byte' does not name a type

[matthijskooijman]

I was going to say that this error doesn't seem related to the #if and you just forgot an include, but the autogenerated #include "Arduino.h" should take care of including/defining those types.

Trying this in the Arduin IDE (1.0.3) confirms the problem. If I remove the #if construct, the code compiles as expected. Looking at the .cpp file the IDE generates from this .ino file, I find it starts with:

matthijs@grubby:~$ cat /tmp/build5957640928641658.tmp/Test2.cpp
#line 1 "Test2.ino"
#ifdef __AVR_ATtinyX5__
#include "Arduino.h"
void setup();
void loop();
#line 2

In other words: The bug is that the IDE inserts the #include after the #if, for some reason. I'm not familiar with the code to find out why this happens, but I guess someone else can take it from here :-)

In the meanwhile, as a workaround you can put some code above the #if statement to make it compile (e.g., something like const int workaround = 0; or something. A #define or a #comment doesn't seem to cut it).

If anyone is looking into this: Perhaps it would be worthwhile to use gcc's -include option to add the Arduino.h include instead of putting it in the generated file?

[ffissore]

Please give a try to the IDEs linked at the bottom of this email on the dev list
https://groups.google.com/a/arduino.cc/forum/#!msg/developers/4X2T3rCxXWM/YNJl6PZuDucJ
We're testing a new preprocessor and it compiles your sketch just fine.

[ffissore]

New preprocessor tracked at #2636. Builds for testing it are available

[ffissore]

Fixed by #3779