Missing prototype in Arduino 1.6.8

[Lauszus]

It seems like Arduino 1.6.8 does not generate the function prototypes for the following examples in the USB Host shield library correctly: https://github.com/felis/USB_Host_Shield_2.0/blob/master/examples/Bluetooth/WiiMulti/WiiMulti.ino and https://github.com/felis/USB_Host_Shield_2.0/blob/master/examples/Bluetooth/PS3Multi/PS3Multi.ino.

More specifically the function prototype void onInit(); does not seem to be properly generated.

This was originally reported by a user at the following issue: felis/USB_Host_Shield_2.0#237.

A workaround for now is just to create the function prototype manually:

void onInit();

The same examples work fine in Arduino 1.6.7.

The full debug output is available here: https://gist.github.com/Lauszus/3daf5e6a5a6dde47b849b72f498dbdc9.

[per1234]

The bug is caused by the function of the same name in the library: https://github.com/felis/USB_Host_Shield_2.0/blob/master/Wii.h#L430.
A simplified sketch that demonstrates the issue is:

class test {
    void asdf() {}
};
void setup() {
  asdf();
}
void loop() {}
void asdf() {}

With Arduino IDE 1.6.8 and 1.6.9 2016/04/28 04:33 this fails to compile. With Arduino IDE 1.6.7 and previous it successfully compiles.

[matthijskooijman]

I suspect #131 would "fix" the original bug (not the testcase @per1234 provided), by not running ctags on the library code, just on the sketch code.

However, looking at the ctags output, this is what is generated for the asdf() method in the last example:

asdf sketch_may03a.ino /^ void asdf() {}$/;" kind:function line:4 class:test signature:() returntype:void

The class:test indicates that this is a method, not a function, but I suspect arduino-builder ignores that, so that should be fixed.

@per1234, thanks for looking into this and pointing out the cause! @facchinm, would you look into fixing this?

[facchinm]

I'm taking a look right now.
Indeed, the Ps3Multi issue is solved by #131 , but @per1234 's simplified example is not (of course). The builder needs to be aware of class tag and skip any function outside the main scope. I'll patch this adding a commit to #131

[matthijskooijman]

#154 should fix this issue completely (both the original one and the testcase from @per1234).

[Lauszus]

@matthijskooijman thanks and @per1234 thanks a lot for tracking down the cause of the bug!

[nitturis]

arduino 1.8.7 has same issue

[2scorpio]

arduino 1.8.13 has same issue