Re: [Lmuse-developer] clang port

[Florian J. <flo...@we...>]

Am 19.05.2012 23:39, schrieb Orcan Ogetbil:
> On Sat, May 19, 2012 at 4:08 PM, Robert Jonsson wrote:
>    
>> Good evening Orcan,
>>
>>      
> Hello!
>
>    
>> 2012/5/19 Orcan Ogetbil<oge...@gm...>:
>>      
>>> Hi all,
>>> I managed to build muse with the llvm/clang compiler on Linux without
>>> too much pain. Two source files needed minor modifications and I had
>>> to modify some cmake files. The compiled binary works fine.
>>>
>>> One issue that I encountered was about the optimization flags. clang
>>> whines when different optimization levels are used among different
>>> files in the same project. Currently the cmake files
>>> synti/organ/CMakeLists.txt (-O2)
>>> synti/simpledrums2/CMakeLists.txt (-O6)
>>> have optimization overrides over the top of the default compile flags.
>>> Does anyone remember why these optimization overrides are there? Can
>>> we remove them?
>>>        
>> Simple drums is Mathias synth and I know for a fact that he runs
>> systems that are, shall we say, behind the upgrade curve ;) Are you
>> there mathias?
>> I could not say for sure but it seems to me that the purpose is only
>> to wring as much speed as possible from them. I can't think of another
>> reason... meaning that it should be safe to align the optimization
>> flags with the others.
>>
>> Then again... these two build synths which are built into their own
>> libraries. Is it the .o files used when linking the .so that have
>> different settings?
>>
>>      
> The situation is subtle. In the current setup the all.h header file
> (and also the all-pic.h which is a copy of all.h) is being precompiled
> as instructed in pch.txt. all.h is currently empty.
>
> Now, we compile each source file with a -include
> ${PROJECT_BINARY_DIR}/all.h flag. Since the all.h was precompiled, the
> compiler prefers to use the precompiled all.h.pch file when it sees
> the above flag while compiling some other source file. And if the
> source  file you are compiling is being compiled with a different
> optimization flag than all.h.pch, clang fails.
>
> Now there are a few solutions:
> - Remove optimization overrides from organ and simpledrums2, as flo suggests
>    
independent from this problem, i'd support that ;)

> - Remove the -include ${PROJECT_BINARY_DIR}/all.h flag from
> everywhere. Since it is empty for the time being, this is not a
> problem. The question is, will it ever get populated?
>    
what's that file for? how could it be used?

> - Remove the -include ${PROJECT_BINARY_DIR}/all.h flag from organ and
> simpledrums2
>    
nah, i don't like this. no special cases please ;). they only makes 
things complicated.

> - Don't precompile all.h
>    
can someone benchmark this? if not precompiling has no notable negative 
performance impact on the time consumed by make clean && make, then i'd 
not precompile it.

greetings
flo
> I know this is really a silly situation, and all solutions are pretty
> much practically equivalent. I just wanted to get your opinion.
>
> Thanks,
> Orcan
>
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Lmuse-developer mailing list
> Lmu...@li...
> https://lists.sourceforge.net/lists/listinfo/lmuse-developer
>
>