[gecode-users] seg fault with posting dom constraint

[Kish Shen]

Hi,

I am running into a seg fault with using the dom constraint.
I am testing the ECLiPSe interface to Gecode with the following ECLiPSe 
code:
     A :: [1..3], A :: [1..2].

Basically, this first set the integer variable (A) with the domain 
interval from 1 to 3, and then constrain the variable with a new 
interval 1 to 2. The seg fault seems to happen with this second call.

The calls to Gecode is done at runtime via the interface code I have 
written, so there is no C++ program, but I have traced the calls via 
gdb, and the following calls to Gecode are done:

setting the initial domain to 1..3:
(GecodeSpace is derived from Space with a IntVarArray vInt)

solver = new GecodeSpace();

solver->vInt.reize(*solver, 1);
solver->vInt[0].init(*solver, 1, 3);

constraining the domain to 1..2

size = 1;
IntVarArgs vars(size);
vars[0] = solver->vInt[0];

dom(*solver, vars, 1, 2);

The seg fault seems to happen in this call to dom(). gdb reports that 
the seg fault happens in int/var-imp/int.hpp:349,

which in my version of gecode is:
   forceinline ModEvent
   IntVarImp::gq(Space& home, int n) {
     if (n <= dom.min()) return ME_INT_NONE;  <--- here

(Sorry I had to type the above by hand -- don't seem to be able to cut 
and paste between a VNC window and my mailer running on the host Windows 
XP).

[As far as I know, I did not compile gecode to be debuggable, but gdb 
nevertheless seem to trace some C++ execution, but I am not sure how 
accurate the indication that the seg fault is in line 349 is]

I am using Gecode 3.0.2, g++ 4.2.1 running on 32 bit x86 Linux.

Am I doing something obviously wrong?

Thanks in advance for any help!

--Kish Shen

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