build options in source comments

[koendv]

This PR allows embedding build options in project .ino source comments, like this:

// build-opt -DUSB_PRODUCT_STRING=\"device\ name\"

void setup() {
  // put your setup code here, to run once:
}

void loop() {
  // put your main code here, to run repeatedly:
}

This way there is no need for a separate build_opt.h file. This also works when using arduino ide 2.0.0.

[fpistm]

Hi @koendv
thanks for this proposal.
At this time I will not merge this as I'd like to have Arduino feedback about arduino/arduino-ide#363 arduino/arduino-cli#1338

[fpistm]

Hi @koendv
Thanks for this PR, it was a great idea anyway I will not merge them.

• PR platform: use build.opt instead of build_opt.h #1442 solves the issue bring by the arduino-CLI
• Comment is only on one line and number of option can be high.
• Syntax have to be strict and I know this will bring support 😉

When Arduino will fix the original issue then I will review this part moreover Arduino study/implement a way to "Provide dedicated sets of "extra flags" properties for platform developers and users"
arduino/arduino-cli#846