[Scons-users] SCons popularity

Sun Jun 14 02:18:51 EDT 2015

Ray,

I might have been mistaken about something which is rather unfortunate.
Apparently, commandline defines don't get placed directly into the
DefaultEnvironment.  I would say this could be done in 1-2 lines of code,
but you will run into the issue of which variable are replaced vs which are
appended...

Maybe we could come up with a scheme for doing this with all internally
supported variables...

I'm a bit sad now,
William

On Sun, Jun 14, 2015 at 1:49 AM, William Blevins <wblevins001 at gmail.com>
wrote:

> Ray,
>
> Variable examples are C/C++.
>
> On Sat, Jun 13, 2015 at 11:50 PM, Ray Sheppard <rsheppar at iu.edu> wrote:
>
>>  Hello William,
>>   I only have experience with the SCons-based packages handed to me. So
>> possibly my issues are with the way those were created and not what is
>> possible.  In general, they assume that they know what directory structures
>> to expect and assume they have write privileges where they don't.
>>
>
> I'm not sure how this is an issue with the tool; might be an issue with
> where the code was located when executed, build requirements failure, etc.
> I would expect general practice to have file writes down the SConstruct
> directory tree, but this is not required.
>
>
>> In addition, they usually "see" a compiler that they should not use and
>> grab it.
>>
>
> SCons has to make some assumption or it wouldn't do anything.  Compiler
> can be overridden via variable like CCCOM.
>
>
>> The fact that it is just a piece of a more complicated compiler with
>> multi-staged compiler flags goes right over its head.
>>
>
> SCons doesn't have a head, but I assume you just want to add compiler
> flags: CCFLAGS?
>
>
>> In general, executables need to be static because execution directories
>> are thousands of clock cycles away from either home directories or system
>> libraries.
>>
>
> I'm not sure how this is an issue with the tool; might be an issue with
> where the code was located when executed, build requirements failure, etc.
> I would expect general practice to have file writes down the SConstruct
> directory tree, but this is not required.
>
>
>> I have posed MPI questions here before that went unresolved.
>>
>
> SCons doesn't support clustering across machines natively; not sure why
> else you might want messaging passing.  There might be a 3-rd party
> extension, but I haven't heard of one.
>
> There is a shared caching mechanism that might be helpful:
> http://www.scons.org/doc/HTML/scons-user/ch24.html
>
>
>> I am not a big fan of Auto-xxx/M4/Configure.  I was happy setting my
>> flags and compilers in a Makefile and letting it go.
>>
>
> Unfortunately, how SCons behaves is up to the build script writer in many
> cases, but any environment variable can be overridden on the SCons command
> line including common ones like LIBPATH, CPPPATH, CCFLAGS, compilers, or
> any other variable.  Here is a bigger list of entries that SCons supports:
> http://www.scons.org/doc/HTML/scons-user/apa.html
>
> There are cases where this will not work if the script writer has
> explicitly env.Replaced the variable in question thus overriding any
> cmdline inputs, but I'm not sure how that can be helped other than via
> communicating build requirements.
>
> We can promote good practices, but we cannot enforced them.  I find that
> many developers learn a tool by  learning just enough to do "anything" and
> brute forcing the rest.  I have on many occasions scolded my own coworkers
> for not trying to lookup the API before they "reinvented the wheel".
>
> However, a simple set of command line flags to override SCons assumptions,
>> similar to ./configure --yyy,  is not widely publicized.
>>
>
> The User Guide is very publicized.
>
> V/R,
> William
>
>
>>                                Ray
>>
>>
>> On 6/13/2015 11:28 PM, William Blevins wrote:
>>
>>
>>
>> On Sat, Jun 13, 2015 at 5:14 PM, Ray Sheppard <rsheppar at iu.edu> wrote:
>>
>>> Hi All,
>>>   For what it is worth, without this functionality, use of SCons on
>>> supercomputers is problematic.
>>>           Ray
>>>
>>> On 6/13/2015 10:44 AM, Vasily wrote:
>>>
>>>>
>>>> Yes, I was talking about those. I believe you can override their
>>>> default values by passing them as arguments, like
>>>> $ scons all INSTALL_ROOT=some-path
>>>>
>>>> That would need some testing, though - I did not try setting it to a
>>>> directory *not* under SConstruct's directory.
>>>>
>>>> Thanks,
>>>> Vasily
>>>>
>>>>
>>>>
>>>
>>  It's not clear what you are implying.
>>
>> SCons supports setting variables on the command line, and SCons supports
>> installing outside the SConstruct directory tree, and supercomputing has
>> nothing to do with either of these items.
>>
>>  V/R,
>>  William
>>
>>
>>>  _______________________________________________
>>> Scons-users mailing list
>>> Scons-users at scons.org
>>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>>
>>
>>
>>
>> _______________________________________________
>> Scons-users mailing listScons-users at scons.orghttps://pairlist4.pair.net/mailman/listinfo/scons-users
>>
>>
>>
>> _______________________________________________
>> Scons-users mailing list
>> Scons-users at scons.org
>> https://pairlist4.pair.net/mailman/listinfo/scons-users
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://pairlist4.pair.net/pipermail/scons-users/attachments/20150614/4df3d0a0/attachment-0001.html>