id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
7507	BGL subgraph copy constructor buggy	Amyn Bennamane <amynbe@…>	Jeremiah Willcock	"Hello,

I store subgraph objects in a std::list.

After this, most of the data contained in subgraphs are lost.

Attached is a minimalist code that creates a root graph and two childen, and then displays them directly, then insert them into a (copy-on-write) list, then displays them again.

The root redisplays too much, and children lose data.

I am on MacOSX with gcc 6; maybe on other platforms the copy would not happen, since I don't modify the graphs between insertion and display.

Here is my output: 

{{{

From the stack: 
(root) graph: 6(0,2) 4(1,2) 
num_edges= 2
subgraph: 0(0,1) 
num_edges= 1
subgraph: 0(0,1) 
num_edges= 1

From list: 
graph: 0(0,1) 1(1,2) 2(1,3) 6(2,5) 3(4,1) 4(4,5) 5(5,3) 
num_edges= 7
graph: 
num_edges= 0
graph: 
num_edges= 0
}}}

"	Bugs	new	To Be Determined	graph	Boost 1.51.0	Problem		copy-on-write, subgraph copy constructor