2.08 and Incompatible Battle Reports

Taqwus · #1 February 25th, 2004, 08:26 PM

There may be #pragmas or compiler options to change reordering behavior, but I'm not too familiar with MSVC.
Wrapping the randomizer in an object and making sure that the "get a random number" method (perhaps as a static method, even) might serve as a hint to the compiler; could be more work than it's worth.

[edit] Making sure that it's not flagged as constant, that is. IOW to encourage the compiler to consider side-effects of function invocation.

[ February 25, 2004, 18:51: Message edited by: Taqwus ]

Pocus · #2 February 25th, 2004, 08:46 PM

I have often battle inconstancies message now, with solo play on windows platform.

Gandalf Parker · #3 February 25th, 2004, 08:57 PM

Way outside of my area but I was thinking that the Devs might have to write their own randomizing routine, and have the host create a seed. Then pass the seed its using inside each of the player files so that the players copy of Dom would definetly use the same routine on the same seed. I never figured on different OSs doing standard math in different orders. Thats insane.

[ February 25, 2004, 18:58: Message edited by: Gandalf Parker ]

Johan K · #4 February 25th, 2004, 09:06 PM

Quote:

Originally posted by Pocus:
I have often battle inconstancies message now, with solo play on windows platform.

Bah, can't you let me be happy for more than 1 hour and 13 minutes.

Peter Ebbesen · #5 February 25th, 2004, 09:15 PM

Quote:

Originally posted by Saber Cherry:
So the moral is actually not to trust Microsoft products, since they take away your control

[/QB]

No, the moral is to be damn careful when using random numbers in sync.

NTJedi · #6 February 25th, 2004, 09:16 PM

I have seen this bug about 3 times for all of the games I have played. It is very rare... and definitely a bizarre bug.

It has worked both ways for me... One battle it showed me losing... yet on the map I won. Another battle it showed me winnning... yet on the map I lost.

2 of these were seen with patch 2.08 installed.

[ February 25, 2004, 19:17: Message edited by: NTJedi ]

Taqwus · #7 February 25th, 2004, 09:29 PM

*scratches head*
'volatile' may also help. The MSDN C++ Language Reference states, "Objects declared as volatile are not used in optimizations because their value can change at any time". Perhaps creating an 'int volatile do_not_reorder_me = 0;' declaration, explicitly separating the computations into multiple lines e.g.
int lhs = lhs_base + invoke_2d6() + do_not_reorder_me;
int rhs = rhs_base + invoke_2d6() + do_not_reorder_me;
would work. I haven't played around with that keyword much however -- been awhile since I wrote MT code.