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[Johannes Ring <johannr@xxxxxxxxx>]

I couldn't reproduce this problem either on my laptop or on any of the
buildbots. However, on my desktop computer at home (running Lucid 64
bit), I ran into the same issue. It happens about half the times when I
run the solver repeatedly. I tried to reconfigure DOLFIN like this:

  scons configure customCxxFlags="-DBOOST_UBLAS_TYPE_CHECK=0"

This got rid of the error message but sometimes the solver completely
hangs and then I have to kill the process:

  johannr@ubuntu-htpc:/tmp$ python solve3.py 
  Matrix of size 16 x 16 has 82 nonzero entries.
  Sorting sparsity pattern.
  Solving linear system of size 16 x 16 (uBLAS Krylov solver).
  Terminated
  johannr@ubuntu-htpc:/tmp$

Anyone else experiencing this behaviour when DOLFIN is configured with
the flag above?

-- 
uBLAS GMRES solver fails on first run
https://bugs.launchpad.net/bugs/594954
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Status in DOLFIN: Confirmed

Bug description:
(reported by Doug Arnold)

After cleaning the instant cache, the solver

from dolfin import *
parameters["linear_algebra_backend"] = "uBLAS"
mesh = UnitSquare(3,3)
V = FunctionSpace(mesh, 'CG', 1)
v = TestFunction(V)
u = TrialFunction(V)
a = u*v*dx
A = assemble(a)
L = v*dx
b = assemble(L)
x = Vector(b.size())
solve(A, x, b, "gmres")
print x.array()

crashes with the message:

Check failed in file /usr/include/boost/numeric/ublas/operation.hpp at line 260:
norm_1 (v - cv) <= 2 * std::numeric_limits<real_type>::epsilon () * verrorbound
Traceback (most recent call last):
  File "solve3.py", line 12, in <module>
    solve(A, x, b, 'gmres')
  File "/home/faculty/arnold/workshop/FEniCS/lib/python2.6/site-packages/dolfin/cpp.py", line 4169, in solve
    return _cpp.solve(*args)
StandardError: internal logic

Searching on the web for the error message came up with this:
  http://archives.free.net.ph/message/20081022.224821.1eddeaa9.da.html
where Gunter Winkler suggests "#define BOOST_UBLAS_TYPE_CHECK 0",
but I don't know how to do this from dolfin.