Re: float bug? perl 5.8, DBI and oracle 10.2.0

On Thu, 2007-07-19 at 09:42 +0200, Erwan Lemonnier wrote:
Hi Tim!

Ah, now it's getting interesting! :)

So I thought :)

Are the two versions of DBD::Oracle built against the same Oracle
version/installation?

No.
The one used by perl 5.6.2 was built against an oracle 9.2.1.0 (unsure
of the exact version, but it was a 9.*). The one used by perl 5.8.5
and perl 5.8.8 was built against an oracle 10.2.0.

What differences are there in the configuration of the two perl versions?

a diff between perl -V for my perl 5.6.2 and perl 5.8.8 shows the
following differences (the other options are in the 'perl -V' I
included in my very first post):

* 5.6.2:
osvers=2.6.9-42.0.2.elsmp
config_args='-Dprefix=/opt/perl-5.6.2'
useperlio=undef
ccflags ='-fno-strict-aliasing -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64'
cppflags='-fno-strict-aliasing'
libs=-lnsl -lgdbm -ldb -ldl -lm -lc -lcrypt -lutil
ccdlflags='-rdynamic'
Compile-time options: USE_LARGE_FILES

* 5.8.8:
osvers=2.6.9-55.elsmp
config_args=''
useperlio=define
bincompat5005=undef
ccflags ='-fno-strict-aliasing -pipe -Wdeclaration-after-statement
-I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64'
cppflags='-fno-strict-aliasing -pipe -Wdeclaration-after-statement
-I/usr/local/include'
libs=-lnsl -ldb -ldl -lm -lcrypt -lutil -lc
gnulibc_version='2.3.4'
ccdlflags='-Wl,-E'
Compile-time options: PERL_MALLOC_WRAP USE_LARGE_FILES USE_PERLIO


Take a look at the source for the Perl_sv_2nv() function in sv.c
in the two distributions.
Also check for differences in the perl config
items that impact that code.

Damn. I had a bad feeling I would end up there.
Ok, I'll put on my deep dive googles and switch on the tolkien
translator. If you don't hear from me within a week, call the asylum
to fetch me ;)

Try it with:

my $v1 = "1.73696";
showbin($v1);
require DBD::Oracle;
my $v2 = "1.73696";
showbin($v2);

I get:

[HEAD] ~/HEAD/test/t/> !1030$ /opt/perl-5.6.2/bin/perl
02_test_require_dbd_oracle.t
0011111111111011110010101001011010010001101001110101110011010001
requiring
0011111111111011110010101001011010010001101001110101110011010001

[HEAD] ~/HEAD/test/t/> !1031$ /opt/perl-5.8.8/bin/perl
02_test_require_dbd_oracle.t
0011111111111011110010101001011010010001101001110101110011010001
requiring
0011111111111011110010101001011010010001101001110101110011010001

No difference. What triggered the problem happened during the connect,
but not during 'require DBD::Oracle'.


I know that on Solaris the act of loading the Oracle library (e.g.
libclntsh.so) could suck in other libraries which would cause
subtle side effects.

The particular case I (vagely) recall related to alarm(). Loading the
Oracle library caused the threaded version of alarm() to be loaded and
take precedence. So alarm(0) after loading DBD::Oracle wouldn't cancel
the alarm($timeout) set before loading it. Fun. I don't recall now
if/how that got resolved.

Anyway, I mention it because it seems like this is a similar issue.

Agggh. This example gives me goose flesh. I just hope I am not facing
something like that...

Is there anyone around with access to an oracle database 10.* and
running perl 5.8.* who could run the test code I provided earlier? The
one that just connects? It would be interesting to know how strongly
dependent it is to just my specific setup...

I know you asked for Oracle 10, but here is the result of

Perl : 5.008006 (i686-linux)
OS : linux (8.0)
DBI : 1.54
DBD::Sponge : 12.008696
DBD::Proxy : 0.2004
DBD::Oracle : 1.19

Oracle 9.2.0.1.0

bin: 0011111111111011110010101001011010010001101001110101110011010001
connecting
bin: 0011111111111011110010101001011010010001101001110101110011010001

--
Scott T. Hildreth <shildreth@xxxxxxxxxxxxxxx>
.

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