Newbie: BGL: g++ -O2 or -O3 gives wrong numbers

From: michael_wangzy (michael_wangzy_at_[hidden])
Date: 2003-06-16 20:42:44

HI,
  I start looking at the Graph library and try the quick_tour.cpp
on my machine. Here is something wrong I found out

> gcc --vesion
gcc (GCC) 3.3 (Gentoo Linux 1.4, PVR 3.3)

> g++ -o test -O2 quick_tour.cpp
> ./test
vertices(g) = A B C D E 
edges(g) = (A,B) (A,D) (C,A) (D,C) (C,E) (B,D) (D,E) 
vertex: 0
        out-edges: (0,134545512) (0,134545536) 
        in-edges: (2,0) 
        adjacent vertices: 134545512 134545536 
vertex: 1
        out-edges: (1,134545632) 
        in-edges: (0,1) 
        adjacent vertices: 134545632 
vertex: 2
        out-edges: (2,134545560) (2,134545608) 
        in-edges: (3,2) 
        adjacent vertices: 134545560 134545608 
vertex: 3
        out-edges: (3,134545584) (3,134545656) 
        in-edges: (0,3) (1,3) 
        adjacent vertices: 134545584 134545656 
vertex: 4
        out-edges: 
        in-edges: (2,4) (3,4) 
        adjacent vertices: 
digraph G {
graph [
rankdir="LR", ratio="fill", size="3,3"];
node [
shape="circle"];
0[label="A"];
1[label="B"];
2[label="C"];
3[label="D"];
4[label="E"];
0->1 [label="1.2"];
0->3 [label="4.5"];
2->0 [label="2.6"];
3->2 [label="0.4"];
2->4 [label="5.2"];
1->3 [label="1.8"];
3->4 [label="3.3"];
}

Note: the large numbers in the out-edges , like 134545512. Expected
numbers are 0,1,2,3,4. Seems some fields are not initilized but read.

Note: I tried gcc-3.2.3 and got same results

Note: Without -O2 it is fine.

My newbie questions are:
1) Is it compiler issue or BGL issue? Cannot we use optimization of
gcc when using BGL?
2) I suppose gcc3.3 is good so if this is an BGL issue, where could
the thing go wrong? How to fix it?

Thanks,

Michael