Re: motor module make error

["Johnson, Andrew N. via Tech-talk" <tech-talk at aps.anl.gov>]

Hi Liang,

On Oct 20, 2021, at 10:22 PM, 网易邮件中心 via Tech-talk <tech-talk at aps.anl.gov> wrote:

     I use centos8, base 7.0.6.1, motor ( https://github.com/epics-modules/motor ), seq-2.2.6, and some other module from https://github.com/epics-modules/.

I suspect this build error may be due to the updated version of g++ that comes with CentOS-8/RHEL-8 which has stricter language rules than the Motor support was written for (Kevin — have you tried building Motor using RHEL-8 yet? I’d expect you to see exactly the same errors there). The code will need to be fixed, but you may be able to get around the problem for now by adding this line somewhere in the middle of the file motor-master/modules/motorOms/omsApp/src/Makefile:

USR_CXXFLAGS = -std=gnu++98

However GCC doesn’t guarantee that you can successfully link together object files that were compiled using two different C++ standards. The version of g++ that comes with CentOS-8/RHEL-8 defaults to using gnu++14, but problems might only arise with the implementations of some of the C++ standard library, which I doubt if the OMS driver is using so I think this is worth trying.

- Andrew

    I got the error message.

--------------------Error----------------------------------------

../drvOmsPC68.cc:148:1: error: invalid conversion from ‘RTN_STATUS (*)(int, const char*, char*)’ {aka ‘RTN_VALUES (*)(int, const char*, char*)’} to ‘RTN_STATUS (*)(int, const char*, const char*)’ {aka ‘RTN_VALUES (*)(int, const char*, const char*)’} [-fpermissive]
 };
 ^
../drvOmsPC68.cc:148:1: error: invalid conversion from ‘char**’ to ‘const char**’ [-fpermissive]
../drvOmsPC68.cc: In function ‘void asynCallback(void*, asynUser*, char*, size_t, int)’:

-- 

Complexity comes for free, simplicity you have to work for.