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Forum Topic - gcc 4.6.1 usage: (4 Items)
   
gcc 4.6.1 usage  
Compile our projets with 4.6.1 and I am happy to report that it's running just fine and give the same output as when 
build with 4.4.2 ;-)

Now I don't have time to test some feature that when turned on in 4.4.2 would create problem ( usage of SSE ), to see if
 they are fixed in 4.6.1, but at least it's a good start.

4.6.1 gives out new interesting warnings that help keep the code clean and tidy ;-)  I like that.

Cheers.
Re: gcc 4.6.1 usage  
Thanks for the feedback. 

Regarding the SSE issue, if its the issue I'm thinking of, then it will require a proc change to 16byte align the 
initial stack so the issue won't be resolved by 4.6 alone.

Regards,

Ryan Mansfield
RE: gcc 4.6.1 usage  
Yep that's the one.

Where we got bitten is that first we removed the -msse when we notice the alignement issue, but I was still crashing. 
Turned out that -O3 and -march=pentium3 was letting the compiler optimize certain operation such a memset with SSE 
instructions, we had to use -mno-sse.  Didn't affect performance much.

Will stack be enough? If I remember right I've seen malloc and new return address not 16bytes aligned (8bytes I believe)
.

Thanks for letting me know.

> -----Message d'origine-----
> De : Ryan Mansfield [mailto:community-noreply@qnx.com]
> Envoyé : 22 juillet 2011 18:27
> À : general-toolchain
> Objet : Re: gcc 4.6.1 usage
> 
> Thanks for the feedback.
> 
> Regarding the SSE issue, if its the issue I'm thinking of, then it will require a
> proc change to 16byte align the initial stack so the issue won't be resolved by
> 4.6 alone.
> 
> Regards,
> 
> Ryan Mansfield
> 
> 
> 
> _______________________________________________
> 
> General
> http://community.qnx.com/sf/go/post87541
> 
Re: RE: gcc 4.6.1 usage  
Greetings,

I had to use -march=i486 (or higher) too because of getting unresolved references to certain built in atomic ops.

A big question from my side: How exactly did you install the new toolchain? To be more exact: What did you copy to the 
target and where? For instance, for the gcc 4.4.2 the is a subdir in the /libs dir with symbolic links to certain .so.4 
libraries -- there is nothing like .so.6 libraries with in these cases available.

Would be nice to get some help,

thanks a lot in advance,
Andy