How to add a compile time configuration option to something in cpukit?

[Ralf Corsepius]

On 09/03/2009 01:41 PM, Sebastian Huber wrote:
> Ralf Corsepius wrote:
>    
>> On 09/03/2009 01:35 PM, Sebastian Huber wrote:
>>      
>>> Ralf Corsepius wrote:
>>>
>>>        
>>>> On 09/03/2009 12:18 PM, Sebastian Huber wrote:
>>>>
>>>>          
>>>>> Hi,
>>>>>
>>>>> the FTP client resides in the cpukit.  It can use gethostbyname() to
>>>>> obtain an
>>>>> internet address from a DNS name.  The dependency on DNS adds 35k of
>>>>> code
>>>>> (THUMB op-codes).  I want to add a configuration option to disable this
>>>>> feature.  Can I add this with RTEMS_CPUOPT in cpukit/configure.ac?
>>>>>
>>>>>            
>>>> As I repeatedly wrote, before: All -m* flags must be global (i.e. *.cfg)
>>>>
>>>> What you are trying to do violates the working principles of multilibs,
>>>> so no way.
>>>>
>>>>          
>>> Sorry now I am a little confused.  What is the connection to multilibs
>>> if I can
>>> enable or disable DNS support in the FTP client?
>>>
>>>        
>> Here:
>>
>>      
>>>    I want to add a configuration option to disable this
>>>   feature.  Can I add this with RTEMS_CPUOPT in cpukit/configure.ac?
>>>        
>> "cpukit/configure.ac"
>>
>>
>>      
> So it is officially impossible to customize the cpukit via configure options?
>    
Very oversimplified, more or less, yes.

Cpukit shares the same philosophy as "libc". Only global compile time 
options are allowed (e.g. optimization levels, enabling/disabling global 
features (.e.g. networking, profiling, ...), etc. ).

Per target/per bsp flags are not permitted, because they will be 
non-functional in multilib'ed configurations.

Ralf