#8 segfault when closing output stream on amd64

[Stefanrh]

Buffer size related segfaults occur when closing output
stream, using otl 4.0.140 with myodb on Debian amd64.

Depending on the data being retrieved, when setting the
buffer to a small enough (<5 when retrieving 256 rows
of three int fields) value, or a large enough value
(511, same example) the segfaults do not occur. On 32
bit debian the segfaults do not occur either.

Here is a gdb backtrace.

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 46912509093024 (LWP 14723)]
0x00002aaaab22431b in mallopt () from /lib/libc.so.6
(gdb) bt
#0 0x00002aaaab22431b in mallopt () from /lib/libc.so.6
#1 0x00002aaaab2231a2 in free () from /lib/libc.so.6
#2 0x00002aaaaac5f4fe in operator delete () from
/usr/lib/libstdc++.so.5
#3 0x00002aaaaac5f539 in operator delete[] () from
/usr/lib/libstdc++.so.5
#4 0x000000000042054e in ~otl_var (this=0x61a708) at
otlv4.h:9386
#5 0x000000000041eab5 in ~otl_tmpl_variable
(this=0x61a6d8) at otlv4.h:3607
#6 0x0000000000410d50 in
otl_tmpl_select_stream<otl_exc, otl_conn, otl_cur,
otl_var, otl_sel, tagTIMESTAMP_STRUCT>::cleanup
(this=0x66cb20) at otlv4.h:5099
#7 0x000000000041b07a in ~otl_tmpl_select_stream
(this=0x66cb20) at otlv4.h:5108
#8 0x000000000041056b in otl_stream::intern_cleanup
(this=0x7fffff8f0440) at otlv4.h:12560
#9 0x000000000040f0b6 in otl_stream::close
(this=0x7fffff8f0440) at otlv4.h:12623