Macro conflict between sys/ioctl.h and hfsm2/machine.hpp

[spiderkeys]

I discovered today that there appears to be a conflict between HFSM2 and the Linux libc sys/ioctl.h header that causes a bizarre cascade of template errors and syntax errors.

The conflict occurs when including sys/ioctl.h before hfsm2/machine.hpp, due to HFSM2's use of the symbol NCC in various template arguments in machine.hpp:
https://github.com/andrew-gresyk/HFSM2/blob/master/include/hfsm2/machine.hpp#L3562

NCC is defined as an integer literal in <bits/ioctl-types.h> which gets included by <sys/ioctl.h>:
https://github.com/raspberrypi/tools/blob/master/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/arm-linux-gnueabihf/libc/usr/include/arm-linux-gnueabihf/bits/ioctl-types.h#L36

After renaming NCC to _NCC in HFSM2, I can confirm that the errors are resolved.

It's a bit unfortunate that the ioctl.h header causes this macro pollution. I'm not sure if there is any better fix than renaming the template argument in HFSM2 or maybe #undef'ing the symbol...

[andrew-gresyk]

Thanks for reporting. I'll rename the arguments to something more obscure.

…

On Tue, Dec 14, 2021, 13:38 Charles Cross ***@***.***> wrote: I discovered today that there appears to be a conflict between HFSM2 and the Linux libc sys/ioctl.h header that causes a bizarre cascade of template errors and syntax errors. The conflict occurs when including sys/ioctl.h before hfsm2/machine.hpp, due to HFSM2's use of the symbol NCC in various template arguments in machine.hpp: https://github.com/andrew-gresyk/HFSM2/blob/master/include/hfsm2/machine.hpp#L3562 NCC is defined as an integer literal in <bits/ioctl-types.h> which gets included by <sys/ioctl.h>: https://github.com/raspberrypi/tools/blob/master/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/arm-linux-gnueabihf/libc/usr/include/arm-linux-gnueabihf/bits/ioctl-types.h#L36 It's a bit unfortunate that the ioctl.h header causes this macro pollution. I'm not sure if there is any better fix than renaming the template argument in HFSM2... — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#63>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AB75T3CLXTDBNAQYDMINVILUQ4UETANCNFSM5KAU3YGA> . Triage notifications on the go with GitHub Mobile for iOS <https://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675> or Android <https://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub>.

[andrew-gresyk]

@spiderkeys
This should be fixed in https://github.com/andrew-gresyk/HFSM2/releases/tag/1.12.1

[spiderkeys]

Hi @andrew-gresyk. I just went to update our HFSM2 to the latest version and it looks like at some point this symbol name switched back from NCC_ to NCC, raising this issue again.

[andrew-gresyk]

Thanks for reporting @spiderkeys
This should be fixed in 2.2.2