On Nov 7, 2018, at 01:32, Ryan Schmidt wrote:
> On Nov 6, 2018, at 17:50, Chris Jones wrote:
>
>> On 6 Nov 2018, at 11:05 pm, Ryan Schmidt wrote:
>>
>>> For Python projects that build using a setup.py file, how do I discover
>>> what options are available -- what's the equivalent of "./configure
>>> --help"? I've tried "python2.7 setup.py --help" and "python2.7 setup.py
>>> build --help" which seem to provide only generic help and not help specific
>>> to this setup.py file.
>>>
>>> Once I know what options are available, how do I provide them to setup.py?
>>> I've tried adding them to build.args, which gives me an "option not
>>> recognized" error.
>>>
>>> I've tried a couple times in recent days, with setup.py files that, based
>>> on my reading of them, provide some custom options that I would like to
>>> use, but I can't figure out how to use them. Can anyone help?
>>
>> Can you post a link to an example of such a file you have been looking at ?
>
> One example is pyobjc-core.
>
> https://bitbucket.org/ronaldoussoren/pyobjc/src/default/pyobjc-core/setup.py
>
> It contains this code:
>
> user_options = [
> ('use-system-libffi=', None, "use the system installation of libffi"),
> ('deployment-target=', None, "deployment target to use (can also be
> set using ${MACOSX_DEPLOYMENT_TARGET})"),
> ('sdk-root=', None, "Path to the SDK to use (can also be set using
> ${SDKROOT})"),
> ]
>
> I assume this means that somehow I should be able to specify the SDK. Yes, I
> could set the SDKROOT environment variable, but that's described as "also";
> that implies there's another way, somehow related to the string "sdk-root=",
> which I would like to understand.
>
> https://trac.macports.org/ticket/53173
Ok I found some insight in the pyobjc-core changelog which documented how to
use this feature when it was added:
https://pythonhosted.org/pyobjc/core/changelog.html
> • The build of pyobjc-core can now be configured by editing setup.cfg (or
> providing arguments to the build_ext command), instead of editing the
> setup.py file.
>
> Currently the following options are availabel for the build_ext command:
>
> • --use-system-libffi: When this option is used the build will use
> /usr/lib/libffi.dylib instead of the embedded copy of libffi. The latter is
> the default is and is better tested.
> • --deployment-target=VAL: The value of MACOSX_DEPLOYMENT_TARGET to
> use, defaults to the deployment target used for building Python itself
> • --sdk-root=VAL: Path to the SDK root used to build PyObjC, or
> “python” to use the default SDK selected by distutils. The default is to use
> the most recent SDK available.
Turns out these are options for the build_ext command, not the build command.
And knowing that, I can now see them described in the help:
$ python2.7 setup.py build_ext --help
Common commands: (see '--help-commands' for more)
setup.py build will build the package underneath 'build/'
setup.py install will install the package
Global options:
--verbose (-v) run verbosely (default)
--quiet (-q) run quietly (turns verbosity off)
--dry-run (-n) don't actually do anything
--help (-h) show detailed help message
--no-user-cfg ignore pydistutils.cfg in your home directory
Options for 'oc_build_ext' command:
--use-system-libffi use the system installation of libffi
--deployment-target deployment target to use (can also be set using
${MACOSX_DEPLOYMENT_TARGET})
--sdk-root Path to the SDK to use (can also be set using
${SDKROOT})
--help-compiler list available compilers
usage: setup.py [global_opts] cmd1 [cmd1_opts] [cmd2 [cmd2_opts] ...]
or: setup.py --help [cmd1 cmd2 ...]
or: setup.py --help-commands
or: setup.py cmd --help
But MacPorts uses the build command, not the build_ext command. I'm guessing
build_ext is one of the commands that build runs internally. So I either have
to use the build_ext command directly, or I have to edit setup.cfg.
Other than by reading project-specific documentation, I'm not sure how I could
have discovered that this build_ext subcommand that we don't use directly had
these options available. So I'm still looking for the equivalent of
"./configure --help" that shows all the available options, regardless of what
subcommand they might apply to.
> Another is pyopencl.
>
> https://github.com/inducer/pyopencl/blob/master/setup.py
>
> It contains these lines:
>
>
> StringListOption("CXXFLAGS", default_cxxflags,
> help="Any extra C++ compiler options to include"),
> StringListOption("LDFLAGS", default_ldflags,
> help="Any extra linker options to include"),
>
> I assume this means I can somehow supply CXXFLAGS and LDFLAGS, but I can't
> figure out how.
>
> https://trac.macports.org/ticket/57520
Haven't figured this one out yet.
> Both of these examples include help strings. I assume there is some command I
> could run that would print all the available options along with their help
> strings. I would like to know what that command is.
