Hello, I first thought the problem might be due to running Linux in a Virtual
Machine, but tried your expression running Linux natively on a very old 32-bit
computer that has only 768MB RAM and 880MB swap space, and of course 32-bit
Linux and GNU-APL. Here are the results:
⎕wa
60051456
⌹?(Q,Q←4000)⍴10
Segmentation fault
WS FULL as expected:
q←4000
r←q,q
s←?r⍴10
⎕wa
291467264
⌹s
WS FULL
⌹s
^^
But then there's this:
q←1500
r←?(q,q)⍴10
⌹r
Segmentation fault
I got these errors running the Debian GNU-APL package, then did the full
compile from apl-1.5.tar.gz dated 3/29/15 from ftp.gnu.org<ftp://ftp.gnu.porg>
and ran gdb as you suggested. The following resulted on the virtual machine
implementation:
⌹?(Q,Q←1500)⍴10
Program received signal SIGSEGV, Segmentation fault.
0x00000000004a41da in divide_matrix (cZ=<optimized out>,
need_complex=need_complex@entry=false, rows=rows@entry=1500,
cols_A=cols_A@entry=1500,
cA=<optimized out>, cols_B=cols_B@entry=1500, cB=0x7ffff04d8010, nB2=1500)
at LApack.cc:93
93 *bb++ = cB[rr + cc*cols_B].get_real_value();
(gdb) bt
#0 0x00000000004a41da in divide_matrix (cZ=<optimized out>,
need_complex=need_complex@entry=false, rows=rows@entry=1500,
cols_A=cols_A@entry=1500,
cA=<optimized out>, cols_B=cols_B@entry=1500, cB=0x7ffff04d8010, nB2=1500)
at LApack.cc:93
#1 0x00000000004ce4b5 in Bif_F12_DOMINO::eval_AB (this=<optimized out>, A=...,
B=...)
at PrimitiveFunction.cc:935
#2 0x00000000004d0f73 in Bif_F12_DOMINO::eval_B (this=0x7f3a80
<Bif_F12_DOMINO::_fun>, B=...)
at PrimitiveFunction.cc:875
#3 0x00000000004c8eb2 in Prefix::reduce_MISC_F_B_ (this=0x880958) at
Prefix.cc:807
#4 0x00000000004c9b29 in Prefix::reduce_statements (this=0x880958) at
Prefix.cc:555
#5 0x000000000051c650 in StateIndicator::run (this=<optimized out>) at
StateIndicator.cc:413
#6 0x0000000000495a25 in Executable::execute_body (this=<optimized out>) at
Executable.cc:247
#7 0x000000000048acda in Command::do_APL_expression (line=...) at
Command.cc:225
#8 0x000000000048ac1a in Command::process_line () at Command.cc:72
#9 0x000000000056c6f5 in Workspace::immediate_execution (exit_on_error=false)
at Workspace.cc:167
#10 0x0000000000442465 in main (argc=<optimized out>, argv=<optimized out>) at
main.cc:372
(gdb)
Hope this helps. Please let me know if you wish other test cases run.
Regards, Rick
________________________________
From: Juergen Sauermann <[email protected]>
Sent: Saturday, January 2, 2016 7:55 AM
To: Blake McBride; Rick Mayforth
Cc: [email protected]
Subject: Re: [Bug-apl] Segmentation fault causes GNU APL version 1.5-1 AMD64 to
exit
Hi,
I am currently trying to reproduce the fault, but was not yet able to.
Like in Blake's case, 1500x1500 worked on my machine.
I am currently trying 4000x4000 but that hasn't finished yet (takes ages).
The expression that I am using is:
⌹?(Q,Q←4000)⍴10
Rick, I suppose you can reproduce the fault more easily. Please try the
following:
1. in the GNU APL src directory, start gdb with GNU APL:
gdb ./apl
run
⌹?(Q,Q←1500)⍴10
2. after the segfault has occurred, print the backtrace (still in gdb):
bt
Thanks a lot,
Jürgen
On 01/02/2016 02:39 PM, Blake McBride wrote:
Just for reference, I tried your example with the head of the source code
repository, and I got:
$ apl
a←1500 1500⍴?(1500×1500)⍴10
⎕wa
732487680
b←⌹a
)off
However, since your ⎕wa was substantially less than mine, it may be that you
ran out of RAM and I didn't.
Also, what version of the GNU APL source code did you start with? (The
repository head is highly recommended.)
Hope this helps.
Blake McBride
On Fri, Jan 1, 2016 at 2:03 PM, Rick Mayforth
<[email protected]<mailto:[email protected]>> wrote:
The following sequence caused the fault. APL exits. The interpreter is running
under Debian 8 in a VMWare virtual machine with 2GB RAM & 880MB swap space. One
would expect a WS FULL or some other APL error in this instance rather than a
forced exit, no?
a←1500 1500 ⍴ ?(1500×1500)⍴10
⎕wa
193433600
b←⌹a
Segmentation fault
