Re: anyone ever crosscompile pvaPy?

["Veseli, Sinisa via Tech-talk" <tech-talk at aps.anl.gov>]

Hi,

On 5/22/20 12:10 PM, Peter Milne wrote:
> Hi Andrew
>
> On 22/05/2020 16:27, Johnson, Andrew N. wrote:
>> Hi Peter,
>>
>> On May 22, 2020, at 3:23 AM, Peter Milne via Tech-talk 
>> <tech-talk at aps.anl.gov<mailto:tech-talk at aps.anl.gov>> wrote:
>>
>> We have a requirement to run pvaPy on a linux-arm system.
>> The ARM system is configured to provide a full EPICS7, Boost lib.
>>
>> Following
>> https://github.com/epics-base/pvaPy/blob/master/README.md
>>
>> Custom Build:
>>
>> Seems to build fine for EPICS_HOST_ARCH=linux-x86_64
>>
>> It's also putting in hooks for linux-arm:
>> ls ./src/pvaccess/O.linux-arm
>> Makefile
>>
> ...
>> pgm TOP ../../.. T_A linux-arm
>> make[3]: Nothing to be done for 'install'.
>> make[3]: Leaving directory 
>> '/home/pgm/PROJECTS/EPICS/pvaPy/src/pvaccess/O.linux-arm'
>> make[2]: Leaving directory '/home/pgm/PROJECTS/EPICS/pvaPy/src/pvaccess'
>> make[1]: Leaving directory '/home/pgm/PROJECTS/EPICS/pvaPy/src'
>>
>>
>> .... does nothing..
>>
>>
>> Is there any way to enable a cross-compile?
>> I don't see any PROD_HOST entries that could be changed to PROD, for 
>> example.
>>
>>
>> The important entry in src/pvaccess/Makefile is the line
>>
>> LOADABLE_LIBRARY_HOST += pvaccess
>>
>> Since pvaPy is a dynamic library that gets loaded by Python, there 
>> are no binaries to create so no use of the PROD or PROD_HOST 
>> variables in the Makefile. Change the above to LOADABLE_LIBRARY and 
>> it should start cross-compiling for your target.
>>
> Yes, that's it!. Thank you. And, really generically the same idea as
> PROD_HOST, should have spotted that.
>
> So, the good news, it's trying to build.
> The bad news, there are errors, maybe just one:
>
> /usr/include/python3.7m/pyconfig.h:4:10: fatal error: pyconfig-32.h:
>
> So the next step is to get it to look at the linux-arm version of the 
> python headers rather than the HOST version..
>
> ... and that suddenly becomes really site-specific..
>
>
The build looks into configure/CONFIG_SITE.local file to determine any 
site specific settings, which might also include a custom python build.

Specifically, variables that can be modified are PVA_PY_CPPFLAGS and 
PVA_PY_LDFLAGS. In one of my builds I have the following:

bluegill2> more configure/CONFIG_SITE.local
PVA_PY_CPPFLAGS = -I/local/sveseli/MARTY/CONDA/include/python3.7m 
-I/local/sveseli/MARTY/opt/boost-python-1.70.0/include
PVA_PY_LDFLAGS = -L/local/sveseli/MARTY/CONDA/lib 
-L/local/sveseli/MARTY/opt/boost-python-1.70.0/lib/linux-x86_64 -lpython3.7m
PVA_PY_SYS_LIBS = boost_python37  boost_numpy37
PVA_API_VERSION = 482
PVA_RPC_API_VERSION = 482
HAVE_BOOST_NUM_PY = 0
HAVE_BOOST_PYTHON_NUM_PY = 1
PYTHON_VERSION = 3.7
PVA_PY_PYTHON = /local/sveseli/MARTY/CONDA/bin/python3
PVA_PY_PYTHONPATH = 
/local/sveseli/MARTY/pvapy-sv/lib/python/3.7/linux-x86_64
PVA_PY_LD_LIBRARY_PATH = 
/local/sveseli/MARTY/CONDA/lib:/local/sveseli/MARTY/opt/boost-python-1.70.0/lib/linux-x86_64
PVA_PY_SPHINX_BUILD = /local/sveseli/MARTY/CONDA/bin/sphinx-build
PVA_PY_EPICS_BASE = /local/sveseli/MARTY/opt/epics-7.0.3.1
PVA_PY_EPICS4_DIR = /local/sveseli/MARTY/opt/epics-7.0.3.1
PVA_PY_HOST_ARCH = linux-x86_64
PVA_PY_SETUP_SH = 
/local/sveseli/MARTY/pvapy-sv/bin/linux-x86_64/pvapy_setup_full.3.7.sh

Automatic configuration should work for the host architecture that you 
are building on, but at the moment it will likely not work for 
cross-compiles.
>
>
>> Hopefully you and Sinisa can work out some way to adjust the build so 
>> cross-builds like this can be configured more easily, but I suspect 
>> it may always need some kind of manual configuration to enable it.
>
> .. as confirmed above.
>
> Should be possible to make a configure/ option of course..
>
> Thanks again Andrew
>
> Cheers
>
>
I talked to Andrew about making this easier.

Sinisa


> Peter
>
>
>
>>
>> - Andrew
>>
>>
>> -- 
>> Complexity comes for free, simplicity you have to work for.
>>
>>
>
>