Issue 1:
Original ticket http://projects.scipy.org/scipy/ticket/351 on 2007-01-19 by @wnbell, assigned to unknown.

from scipy import *

M = sparse.csr_matrix(rand(6,6))
b = rand(M.shape[0])

lu = linsolve.splu(M) #crash here

Produces the output:

nathan@droog:~/Work/hirani_group/projects/pydec/multigrid/scratch$ python splu.py
Use minimum degree ordering on A'+A.
Segmentation fault (core dumped)
nathan@droog:~/Work/hirani_group/projects/pydec/multigrid/scratch$ gdb python
(gdb) run -i splu.py
Starting program: /usr/bin/python -i splu2.py
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread -1209776464 (LWP 17999)]
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
Use minimum degree ordering on A'+A.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread -1209776464 (LWP 17999)]
0xb696b141 in mmdelm_ (mdnode=0xb697e21c, xadj=0x839c4a8, adjncy=0x841ea60, dhead=0x83d3148, dforw=0x8349a40, dbakw=0x835d4c8, qsize=0x834c6f0, llist=0x83e1e80, marker=0x83907d8, maxint=0xbfe64d94, tag=0xb697e214)
at Lib/linsolve/SuperLU/SRC/mmd.c:366
366 nabor = adjncy[i];
(gdb) bt
#0 0xb696b141 in mmdelm_ (mdnode=0xb697e21c, xadj=0x839c4a8, adjncy=0x841ea60, dhead=0x83d3148, dforw=0x8349a40, dbakw=0x835d4c8, qsize=0x834c6f0, llist=0x83e1e80, marker=0x83907d8, maxint=0xbfe64d94, tag=0xb697e214)
at Lib/linsolve/SuperLU/SRC/mmd.c:366
#1 0xb696c3fb in genmmd_ (neqns=0xbfe64da4, xadj=0x839c4a8, adjncy=0x841ea60, invp=0x8349a40, perm=0x835d4c8, delta=0xbfe64d98, dhead=0x83d3148, qsize=0x834c6f0, llist=0x83e1e80, marker=0x83907d8, maxint=0xbfe64d94,
nofsub=0xbfe64d90) at Lib/linsolve/SuperLU/SRC/mmd.c:186
#2 0xb6964161 in get_perm_c (ispec=2, A=0xbfe65000, perm_c=0x8349a40) at Lib/linsolve/SuperLU/SRC/get_perm_c.c:423
#3 0xb6951d53 in newSciPyLUObject (A=0xbfe65000, diag_pivot_thresh=1, drop_tol=0, relax=1, panel_size=10, permc_spec=2, intype=12) at Lib/linsolve/_superluobject.c:360
#4 0xb6951203 in Py_dgstrf (self=0x0, args=0xb6dd366c, keywds=0x0) at Lib/linsolve/_dsuperlumodule.c:206
#5 0x080b901a in PyEval_EvalFrame ()
#6 0x080ba4b9 in PyEval_EvalCodeEx ()
#7 0x080b86ea in PyEval_EvalFrame ()
#8 0x080ba4b9 in PyEval_EvalCodeEx ()
#9 0x080ba527 in PyEval_EvalCode ()
#10 0x080ddb1a in PyRun_FileExFlags ()
#11 0x080ddd07 in PyRun_SimpleFileExFlags ()
#12 0x08055cc2 in Py_Main ()
#13 0x08055132 in main ()
(gdb)

The crash does not occur every time the program is run via python (although almost always). Within gdb the error occurs very very rarely, and is hard to reproduce.

Python 2.4.4c1
gcc (GCC) 4.1.2 20060928 (prerelease) (Ubuntu 4.1.1-13ubuntu5)

Issue 2:
Original ticket http://projects.scipy.org/scipy/ticket/1472 on 2011-07-03 by @rgommers, assigned to @pv.

On Python 2.6 (32-bit) under OS X, with numpy 1.6.1rc2.

Complete gdb output attached, relevant bit is:

test_arpack.test_hermitian_modes(True, <std-hermitian>, 'F', 2, 'LM', None, 0.5, <function aslinearoperator at 0x2a55a30>) ...
Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_INVALID_ADDRESS at address: 0x07723a70
0x9357bc00 in ATL_zaxpy_xp0yp0aXbX ()
(gdb) bt
#0 0x9357bc00 in ATL_zaxpy_xp0yp0aXbX ()
#1 0x9357ba60 in ATL_zaxpy ()