Infinite Loop in Deformable World Simulation Step

[edwin-pan]

I had been using an older version of Bullet for simulating deformable objects (works quite well). Today, while switching to the latest hotness, I now run into an infinite loop in the buildTreeBottomUp(...) function in btSoftBody.cpp. Specifically, I moved from this version of btSoftBody.cpp to this version.

In the first pass call to buildTreeBottomUp(...) from here, the tree build has values of N:
N: 400,N: 226,N: 133,N: 84,N: 57,N: 43,N: 35,N: 31,N: 29,N: 28,N: 27,N: 26,N: 25,N: 24,N: 23,N: 22,N: 21,N: 20,N: 19,N: 18,N: 17,N: 16,N: 15,N: 14,N: 13,N: 12,N: 11,N: 10,N: 9,N: 8,N: 7,N: 6,N: 5,N: 4,N: 3,N: 2
and then continues onward.

The next call to buildTreeBottomUp(...) happens in the rebuildNodeTree(...) call and can be found here, and the tree rebuild gets stuck at N=17:
N: 274,N: 148,N: 84,N: 52,N: 37,N: 29,N: 25,N: 23,N: 22,N: 21,N: 20,N: 19,N: 18,N: 17,N: 17,N: 17,N: 17,N: 17, .............

What is the purpose of this tree rebuilding process and how might I go about debugging this?

[36yang]

I also encountered the same problem