Re: Major improvement to the Xconq kernel

[Eric McDonald <mcdonald at phy dot cmich dot edu>]

On Thu, 13 Nov 2003, Jim Kingdon wrote:

> > A new path-finding code by Peter Garrone has just been checked in. It uses

> * One case where an infantry just sat there in one my my towns, about
>   3-5 hexes short of its destination.  It was apparently using up its
>   ACP on each turn.  Won't be able to do anything about this unless I
>   notice it happening again (as in, I'm not even 100% sure it was
>   really a bug I saw).

I've seen this happen too (with the new path code). If you look at 
the unit's info display, does it list the movement task with a "x 
0" next to it for the entire turn?

> * One SIGSEGV.  Most interesting part of the stack trace follows.
>   Because the default compilation uses -O, it is hard to quickly
>   look at the variables at that point.

For the modern GNU C compilers, configure reports -O as part of 
the default CFLAGS. (I think I heard somewhere, perhaps on the 
gcc list, that -O and -g should now be able to work together 
without significant problems.)  My experience has been that if 
the two are used together, then sometimes you need to step a few 
lines before GDB will "backtrack" to the variable in question and 
show its assigned value; I assume that this is simply because the 
optimizer reorders instructions and it is harder to know when to 
associate a line with an instruction.

I can filter -O out of the default CFLAGS for the GNU compilers, 
if there is a consensus that this should be done. I know that 
Peter is leary about debugging optimized code.

Eric