Re: [Module-build-general] "0" options in compilation lines?

[Randy W. S. <RandyS@ThePierianSpring.org>]

On 2/25/2003 10:24 PM, Ken Williams wrote:
> 
> On Tuesday, February 25, 2003, at 06:56  PM, Randy W. Sims wrote:
> 
>> On 2/24/2003 1:04 PM, Ken Williams wrote:
>>
>>> I was wondering about the check for boolean truth, which will turn 
>>> argument lists like ('-foo', 0) into ('-foo').  Maybe it would be 
>>> safer to just use grep {defined()}, or grep {defined() && length()}, 
>>> or something?  Or are there some zeroes you're specifically trying to 
>>> filter out?
>>>  -Ken
>>
>>
>> Your right. Bad habbit. I know it's bad for me, but I can't stop...
>>
>> I can't think of anyway in which it might fail, but it should be changed.
> 
> 
> How about I just change it to
> 
>   return [
>     $spec{cc}, '-c'         ,
>     @{$spec{includes}}      ,
>     @{$spec{cflags}}        ,
>     @{$spec{optimize}}      ,
>     @{$spec{defines}}       ,
>     @{$spec{perlinc}}       ,
>     "-Fo$spec{output}"      ,
>     $spec{source}           ,
>   ];
> 
> ?  Seems like we'll want to know if one of those values is undefined 
> anyway, so we'll want to trigger the warning if warnings are turned on.
> 
>  -Ken

That wouldn't work as it's written. Just before the return there is a 
call to write_*_script() which delete()s the elements in the hash that 
it is able to write to the script file, so it needs to be grep{defined 
&& length} to avoid warnings about the no longer existing elements.

I've attached a patch that fixes that and fixes a couple of 
inconsistencies in the way I was access $self->{config} (i.e. in most 
places I was accessing through the convenience variable $cf while in a 
couple of spots I spelled it out $self->{config}).

In regards to warning users about undefined entries, I think it is valid 
for some options to be undefined, but I really don't know enough about 
typical usage across the various platforms to test the validity of 
options. I need to study modules like MakeMaker and others that use the 
compiler to see what they do, as well as studing some Makefile.PLs and 
the generated Makefiles to try to get a better grasp on how the compiler 
and linker are generally used.

Randy.