Perl cgi compilation error in autovivication.pm - apache

Question

I'm using a perl cgi script that uses our own libraries, which use the "no autovivification" pragma. E.g.
/usr/lib/company/mysim.cgi:
#!/usr/bin/perl -w
use strict;
# ... other use
use Company::Module1;
/usr/lib/perl5/Company/Module1.pm
package Company::Module1;
no autovivification;
use strict;
use warnings;
Approximately 50% of the time, when accessing the URL to reach the cgi script the compilation fails with...
[Fri Dec 04 15:40:10.744901 2015] [:error] [pid 30455:tid 2961136448] Bareword "A_HINT_STRICT" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nBareword "A_HINT_WARN" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nBareword "A_HINT_FETCH" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nBareword "A_HINT_STORE" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nBareword "A_HINT_EXISTS" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nBareword "A_HINT_DELETE" not allowed while "strict subs" in use at /usr/lib/i386-linux-gnu/perl5/5.20/autovivification.pm line 144.\nCompilation failed in require at /usr/lib/company/mysim.cgi line 14.\nBEGIN failed--compilation aborted at /usr/lib/company/mysim.cgi line 14.\n
(taken from /var/log/apache2/ssl/error.log as this script sits on the https port).
My environment is:
- debian jessie (8.2)
- tomcat7
- apache2 (2.4)
- perl 5.20.2
- libautovivification-perl 0.12-1+b1
My questions are:
Has anyone seen this before? It seems odd that the autovivification module fails to compile due to a "use strict" pragma.
Can anyone explain the intermittent nature of the compilation error? Even more odd, the cgi fails to compile ~half the time, and works fine (i.e. runs and returns expected results) the other ~half.
Thanks for your time.
09/12/2015: Some additional information...
Thanks all for the feedback.
There's no explicit creation of threads, though this is in the context of apache so there's presumably threading of requests.
The root cause does seem to be a failure in the XSLoader. At least this minimal working example...
package autovivification;
use 5.008_003;
use strict;
use warnings;
our $VERSION;
BEGIN {
$VERSION = '0.12';
}
BEGIN {
require XSLoader;
XSLoader::load(__PACKAGE__, $VERSION);
}
my %bits = (
strict => A_HINT_STRICT,
warn => A_HINT_WARN,
fetch => A_HINT_FETCH,
store => A_HINT_STORE,
exists => A_HINT_EXISTS,
delete => A_HINT_DELETE,
);
compiles, whereas this
package autovivification;
use 5.008_003;
use strict;
use warnings;
our $VERSION;
BEGIN {
$VERSION = '0.12';
}
#BEGIN {
# require XSLoader;
# XSLoader::load(__PACKAGE__, $VERSION);
#}
my %bits = (
strict => A_HINT_STRICT,
warn => A_HINT_WARN,
fetch => A_HINT_FETCH,
store => A_HINT_STORE,
exists => A_HINT_EXISTS,
delete => A_HINT_DELETE,
);
fails with the same error.
So, I'll go a-poking around for a load error in the apache logs.... somewhere.
Thanks again for your time.
16/12/2015: Update - Fixed
The root cause was mod_perl, combined with a (possible) change between apache 2.2 and 2.4. The apache configuration for the script, which gives it a ScriptAlias URI of /cgi-bin/script, occurs before setting up the URI /cgi-bin to be handled by mod_perl. In apache 2.2, this ordering seems to be important and the script was not handled by mod_perl. However, in apache 2.4 the ordering does not seem to be important and the script is now handled by mod_perl.
The error arose because this script was not (and never meant to be) handled by mod_perl. The fix was to change the URI for the script to /somethingelse/script.
Thanks to everyone for the comments.

Answer 1

The root cause was mod_perl, combined with a (possible) change between apache 2.2 and 2.4. The apache configuration for the script, which gives it a ScriptAlias URI of /cgi-bin/script, occurs before setting up the URI /cgi-bin to be handled by mod_perl. In apache 2.2, this ordering seems to be important and the script was not handled by mod_perl. However, in apache 2.4 the ordering does not seem to be important and the script is now handled by mod_perl.
The error arose because this script was not (and never meant to be) handled by mod_perl. The fix was to change the URI for the script to /somethingelse/script.
– HalfOpenedEye