Re: [hatari-devel] Hatari profiler updates and CPU cycle questions

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Hi,

On torstai 31 tammikuu 2013, Douglas Little wrote:
> > Ok, thanks for testing it.  For now I'm assuming it's
> > an issue with your GCC version.  :-)
> 
> Can I ask you which version are you using? This was built with v4.5.3. 

v4.4.5 i.e. it probably does less aggressive optimizations than
your newer GCC version.  I think GCC 4.5 started using extra aliasing
optimizations at higher optimization levels.

Do you see any compiler warnings from code under src/debug/ directory
if you rebuild those objects?


> I have been using this version quite a lot for other C/C++ projects
> and haven't noticed any code generation bugs so far - but it is possible
> I suppose.

On x86 encountering GCC bugs is are really rare/corner case
due to better testing.  On ARM they're not so rare...

CMake / Hatari defaults to -O3.

When you have extra time, you might try whether the bug goes away
with -O1:
- if yes, please try also with -O2,
- if not, try with -O0.

That should give a fairly good pointer on whether and what what
kind of optimizations trigger the issue.

(I might then do some searches to GCC bug tracker.)

GDB watchpoints on Hatari disassembler column position variables
would be nice as your crash seemed to happen due to corrupted
disassembler output column position.


	- Eero



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