arduino-builder in 1.6.6 doesn't pick up NRF51 and other expected macros

[george-hawkins]

I know the 1.6.5 Arduino IDE is the currently recommended version for nRF51822-Arduino - this is a heads up and explanation of a breaking change that seems to have been introduced in 1.6.6.

If your .ino file (or a header it includes) depends on the NRF51 macro (or any of the other normally defined macros) then it will break with 1.6.6.

This is because arduino-builder (that converts a .ino into a .cpp) uses a different recipe to the normal cpp recipe and this recipe does not currently pick up all the additional defines like NRF51.

Here's how to see the source of the problem - if you download and unpack arduino-1.6.6-linux64.tar.xz you'll find arduino-1.6.6/hardware/platform.txt - open it in an editor and you'll see the lines:

preproc.includes.flags=-w -x c++ -M -MG -MP
recipe.preproc.includes="{compiler.path}{compiler.cpp.cmd}" {preproc.includes.flags} -DF_CPU={build.f_cpu} -DARDUINO={runtime.ide.version} -DARDUINO_{build.board} -DARDUINO_ARCH_{build.arch} {compiler.cpp.extra_flags} {build.extra_flags} {includes} "{source_file}"

The crucial thing is that it doesn't include all the defines (such as -DNRF51) then we see in compiler.cpp.flags in nRF51822-Arduino/arduino-1.6.x/hardware/RBL/RBL_nRF51822/platform.txt:21, i.e.:

compiler.cpp.flags=-c -g -Os -w -std=gnu++98 -fno-common -fmessage-length=0 -Wall -fno-exceptions -ffunction-sections -fdata-sections -fomit-frame-pointer -nostdlib --param max-inline-insns-single=500 -fno-rtti -DBLE_STACK_SUPPORT_REQD -DDEBUG_NRF_USER -DNRF51 -DTARGET_NRF51822 -DTARGET_M0 -DTARGET_CORTEX_M -DTARGET_NORDIC -DTARGET_NRF51822_MKIT -DTARGET_MCU_NRF51822 -DTOOLCHAIN_GCC_ARM -DTOOLCHAIN_GCC -D__CORTEX_M0 -DARM_MATH_CM0 -DMBED_BUILD_TIMESTAMP=1435023129.97 -D__MBED__=1 

If you scroll over above you'll see that recipe.preproc.includes expects to pick up compiler.cpp.extra_flags rather than compiler.cpp.flags as defined in RBL_nRF51822/platform.txt.

Note: oddly it's not clear where the file arduino-1.6.6/hardware/platform.txt comes from - if I clone the Arduino code base and checkout revision 0992606 that's supposed to correspond to 1.6.6 I can't find any equivalent file.

[george-hawkins]

Solved: I got things to work with the latest version of the Arduino IDE - i.e. 1.6.6.

The Arduino people have been fiddling about a lot with platform.txt in recent IDE releases and the nRF51822-Arduino/.../platform.txt has drifted apart a bit from the layouts now used in the Arduino repository.

So I rearranged nRF51822-Arduino/.../platform.txt to match as closely as possible the layout of the Arduino SAM platform.txt (except for the Avrdude section which I rearranged to match up as much as possible with the Avrdude section if the AVR platform.txt).

I did all this while keeping all the RBL specific behavior (and removed some elements that are no longer required in the newer IDE releases).

The only really important thing was to separate out the RBL specific #defines like NRF51 into the properties compiler.c.extra_flags and compiler.cpp.extra_flags so that the IDE's .ino converter can pick up compiler.cpp.extra_flags.

Other than doing this the only real addition that I made was to add the -DNRF51_S130 define that @sandeepmistry already proposed in issue #41 so that one knows that the S130 soft device is being used.

Here is the new platform.txt that will work with version 1.6.6 of the Arduino IDE. Despite looking very different, it is equivalent to nRF51822-Arduino/.../platform.txt at revision c6d7669, i.e. the latest version existing on Dec 6, 2015.

PS best of luck with the DUO Kickstarter - I'm looking forward to receiving mine 😄

[Cheong2K]

@george-hawkins,
Thank you for your good work and support, we will do more better with the open source world!
--Cheong