Oops,

I clearly forgot to mention that I indeed was worried
about the system crash. Although the kernel served me well for months, I
discarded it and I switched to a "official" stable kernel,
recompiled Gcc & Glibc just for good measure. Nor more
system crashes as noted in my first post last week. The feedback was
right; a program crash should be handled by the OS.

That is why I promised to do a follow-up. I purposely installed two
clean distributions, with proper, stable, non-patched kernels.
Unfortunately the MegaPov behaviour persisted, but those collapses were
handled correctly by the O.S. I did not mention "system crashes" at all
in my follow-up.

Thorsten Froehlich wrote:
> Which is 99.9% of all cases indicates either a bug in the programs, the
> compiler performing certain optimizations or a user misunderstanding the
> proper configuration of compiler optimization options.  Of course, this
> also has nothing to do with the problem at hand.
Could you please explain? This could be exactly the problem we deal
with. MegaPov could have bugs; 1.2.1 is a bug-release, and the
./configure script could have generated compiler flags which uncovers
these bugs. Remember, ./configure is dynamic script, trying to make
educated guess to which compiler flags are best for your specific
Unix-box. Thats why I started hard-coding these flags, in order to make
sure I could produce a correct binary for my machine.

> Nothing strange can happen, the behavior is complete deterministic
> (except of certain generations of P1s, of course ;-) ) and completely
> predictable. And this also has nothing to do with the problem at hand.
Sorry, joyfull language obscured the message: it is deterministic: it dies.

> No, it is you who does not understand what many people have told you so
> far:  Somehow you have run into a dead end and are now pushing against a
> wall, not listing to anybody else who is trying to tell you to just turn
> around to get out of the deadened and find a solution to your problem ;-)
See first paragraph. I did address the kernel issue right away. I try to
be open-minded.

> Nobody can reproduce your bug 
No-one has either confirmed, nor rejected the bug.

> ..include a stack trace....
I'd love to. I will google for a HowTo.

Are you realy sure about the --fast-math ? It is just so typical for
MegaPov, with all the physics code and the ininitesimal calculations
associated. I have seen so many physical simulations die because the
approximations were approaching Zero en there was just not enough
boudary checking..because there never is time/imagination to prevent
them all... I hated it too when wrote those programs.

Anyway, I try to cooperate :)

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