[patch, make machinery, plugins] enable plugins for powerpc-apple-darwin

[IainS]

On 13 May 2010, at 15:22, Richard Guenther wrote:

> On Thu, May 13, 2010 at 3:57 PM, IainS <developer@sandoe-acoustics.co.uk 
> > wrote:
>> Since we use "-mdynamic-no-pic" by default when building gcc on  
>> darwin, and
>> this conflicts with fPIC (needed for plugins),  we need different  
>> flags when
>> building (and testing for ability to build) plugins.
>>
>> the change to gcc/configure.ac deals with this for the test phase  
>> (and
>> actually ensures that fPIC is passed in CFLAGS for other targets  
>> too).
>
> Why do you need to do that change?

without this the test fails (mdynamic-no-pic conflicts with fPIC  
producing a warning) and plugin support is disabled after stage1.

mdynamic-no-pic is added to BOOT_CFLAGS in config/mh-ppc-darwin with  
the comment that it produces 3..5% improvement in compile performance,  
thus I am loath to remove it completely.

If you mean why add fPIC to CFLAGS for other targets? - just for  
tidiness sake (I meant to remove it from LDFLAGS too).

iain.

>> I've put a filter in config/x-darwin to remove the "-mdynamic-no- 
>> pic" from
>> PLUGINCFLAGS since, at present, there is no mechanism to specify  
>> these
>> separately - since they are substituted from:
>>  PLUGINCFLAGS = @CFLAGS@
>>
>> (I wonder if the latter was really intended)
>>
>> ===
>>
>> With this patch all the gcc plugins pass..
>> ... unfortunately, some of the g++ ones do not - although AFAICT  
>> those fails
>> are not due to build issues (they fail at runtime rather than build- 
>> time).
>>
>> [all the plugins pass for powerpc64-apple-darwin, if that provides
>> additional clues...].
>>
>> (to run the plugins also requires :
>> http://gcc.gnu.org/ml/gcc-patches/2010-05/msg00872.html  )
>>
>> ===
>>
>> OK for trunk ?
>>
>> Iain
>>
>> gcc/Changelog:
>>
>>        * configure.ac: Strip "-mdynamic-no-pic" from CFLAGS when  
>> testing for
>> plugin capability on Darwin.
>>        * configure: Regenerated.
>>        * config/x-darwin: Strip  "-mdynamic-no-pic" from  
>> PLUGINCFLAGS.
>>
>>
>>
>>
>>