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Compiler warning without line number

by QM (Vicar)
on Feb 02, 2008 at 17:16 UTC ( #665749=perlquestion: print w/ replies, xml ) Need Help??
QM has asked for the wisdom of the Perl Monks concerning the following question:

I have some defective code, which on one version of Perl doesn't emit a line number:
#!/your/perl/here use strict; use warnings; my $x = q/Just Another Perl Hacker/; if ($x =~ m/(?The Purl Caretakers' John)/) { print "Anagram Regex?\n"; } exit;
(The (? should be (?:.)

On a Linux build of 5.8.0:

Linux% perl -c 665749.pl Sequence (?T...) not recognized in regex; marked by <-- HERE in m/(?T +<-- HERE he Purl Caretakers' John)/
Of course, this is easy to find, as it's a short program. But it doesn't list the offending file (or module), so it may be more difficult to find in a real application.

For comparison, here's ActiveState's 5.8.8:

Windows XP>perl -c 665749.pl Sequence (?T...) not recognized in regex; marked by <-- HERE in m/(?T +<-- HERE he Purl Caretakers' John)/ at 665749.pl line 8.

The full Linux build info:

Linux% perl -V Summary of my perl5 (revision 5.0 version 8 subversion 0) configuratio +n: Platform: osname=linux, osvers=2.4.21-25.elsmp, archname=i386-linux-thread-m +ulti uname='linux porky.build.redhat.com 2.4.21-25.elsmp #1 smp fri nov + 12 21:34:51 est 2004 i686 i686 i386 gnulinux ' config_args='-des -Doptimize=-O2 -g -pipe -march=i386 -mcpu=i686 - +Dmyhostname=localhost -Dperladmin=root@localhost -Dcc=gcc -Dcf_by=Red + Hat, Inc. -Dinstallprefix=/usr -Dprefix=/usr -Darchname=i386-linux -Dvendorprefi +x=/usr -Dsiteprefix=/usr -Dotherlibdirs=/usr/lib/perl5/5.8.0 -Duseshr +plib -Duse hreads -Duseithreads -Duselargefiles -Dd_dosuid -Dd_semctl_semun -Di_d +b -Ui_ndbm -Di_gdbm -Di_shadow -Di_syslog -Dman3ext=3pm -Duseperlio - +Dinstallus binperl -Ubincompat5005 -Uversiononly -Dpager=/usr/bin/less -isr' hint=recommended, useposix=true, d_sigaction=define usethreads=define use5005threads=undef useithreads=define usemulti +plicity=define useperlio=define d_sfio=undef uselargefiles=define usesocks=undef use64bitint=undef use64bitall=undef uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS + -DDEBUGGING -fno-strict-aliasing -I/usr/local/include -D_LARGEFILE_S +OURCE -D_F LE_OFFSET_BITS=64 -I/usr/include/gdbm', optimize='-O2 -g -pipe -march=i386 -mcpu=i686', cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBUGGI +NG -fno-strict-aliasing -I/usr/local/include -I/usr/include/gdbm' ccversion='', gccversion='3.2.3 20030502 (Red Hat Linux 3.2.3-54)' +, gccosandvers='' intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234 d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=1 +2 ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t', + lseeksize=8 alignbytes=4, prototype=define Linker and Libraries: ld='gcc', ldflags =' -L/usr/local/lib' libpth=/usr/local/lib /lib /usr/lib libs=-lnsl -lgdbm -ldb -ldl -lm -lpthread -lc -lcrypt -lutil perllibs=-lnsl -ldl -lm -lpthread -lc -lcrypt -lutil libc=/lib/libc-2.3.2.so, so=so, useshrplib=true, libperl=libperl.s +o gnulibc_version='2.3.2' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynami +c -Wl,-rpath,/usr/lib/perl5/5.8.0/i386-linux-thread-multi/CORE' cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib' Characteristics of this binary (from libperl): Compile-time options: DEBUGGING MULTIPLICITY USE_ITHREADS USE_LARGE_ +FILES PERL_IMPLICIT_CONTEXT Locally applied patches: MAINT18379 Built under linux Compiled at Dec 13 2005 16:27:05 %ENV: PERL5LIB="/home/somebody/perl/lib" @INC: /home/somebody/perl/lib/i386-linux-thread-multi /home/somebody/perl/lib /usr/lib/perl5/5.8.0/i386-linux-thread-multi /usr/lib/perl5/5.8.0 /usr/lib/perl5/site_perl/5.8.0/i386-linux-thread-multi /usr/lib/perl5/site_perl/5.8.0 /usr/lib/perl5/site_perl /usr/lib/perl5/vendor_perl/5.8.0/i386-linux-thread-multi /usr/lib/perl5/vendor_perl/5.8.0 /usr/lib/perl5/vendor_perl /usr/lib/perl5/5.8.0/i386-linux-thread-multi /usr/lib/perl5/5.8.0 .

Is this a known problem with 5.8.0? I did a search, but I don't think I can say with confidence that this issue hasn't been raised somewhere.

Update: In the original post, I replaced the shebang section with something simpler, which changed the actual line number reported. I've updated the error message to reflect the actual code posted.

-QM
--
Quantum Mechanics: The dreams stuff is made of

Comment on Compiler warning without line number
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Re: Compiler warning without line number
by superfrink (Curate) on Feb 03, 2008 at 00:18 UTC
    I don't know the answer but 5.8.4 and 5.8.8 seem okay. On Fedora 6:
    $ perl asdf.pl Sequence (?T...) not recognized in regex; marked by <-- HERE in m/(?T +<-- HERE he Purl Caretakers' John)/ at asdf line 8. $ perl -v This is perl, v5.8.8 built for i386-linux-thread-multi
    On Slackware 10.0:
    [chad@thepurplebuffalo ~]$ perl asdf Sequence (?T...) not recognized in regex; marked by <-- HERE in m/(?T +<-- HERE he Purl Caretakers' John)/ at asdf line 8. [chad@thepurplebuffalo ~]$ perl -v This is perl, v5.8.4 built for i486-linux
Re: Compiler warning without line number
by syphilis (Canon) on Feb 03, 2008 at 00:23 UTC
    Is this a known problem with 5.8.0?

    I get the same as you with ActiveState's 5.8.8, but ActiveState's 5.8.0 omits the line number (same as 5.8.0 on linux).

    We're left to conclude that either it *was* a known issue, or that it was fixed accidentally :-)

    Cheers,
    Rob
Re: Compiler warning without line number
by Util (Priest) on Feb 03, 2008 at 00:35 UTC

    On OS X, I verified that the problem existed in Perl 5.8.0 and 5.8.1, and was fixed in 5.8.2.
    Here are the relevant parts of the 5.8.2 changelog, and the P5P messages:

    http://www.nntp.perl.org/group/perl.perl5.porters/2003/10/msg84468.html

    From: Slaven Rezic
    Date: October 31, 2003 04:24
    Subject: [PATCH] Off-by-one error in regcomp.c
    In regexp error messages, file and line are not printed due to
    an off-by-one error in regcomp.c. This patch fixes the problem
    --snip--
    --- regcomp.c.orig 2003-10-31 13:07:52.000000000 +0100 +++ regcomp.c 2003-10-31 13:08:07.000000000 +0100 @@ -5045,7 +5045,7 @@ S_re_croak2(pTHX_ const char* pat1,const if (l1 > 512) l1 = 512; Copy(message, buf, l1 , char); - buf[l1] = '\0'; /* Overwrite \n */ + buf[l1-1] = '\0'; /* Overwrite \n */ Perl_croak(aTHX_ "%s", buf); }
    --snip--
    http://www.nntp.perl.org/group/perl.perl5.porters/2003/10/msg84501.html
    Thanks, applied as change #21591.
    http://search.cpan.org/src/NWCLARK/perl-5.8.2/Changes
    [ 21606] By: nicholas on 2003/11/01 14:58:31 Log: Integrate: [ 21591] Subject: [PATCH] Off-by-one error in regcomp.c From: Slaven Rezic <slaven@rezic.de> Date: Fri, 31 Oct 2003 12:16:11 +0000 Message-Id: <1067602571.12768@devpc01.iconmobile.de> [ 21593] Test nit ; goes with change 21591 Branch: maint-5.8/perl !> regcomp.c t/lib/warnings/regcomp t/op/regmesg.t

      Thanks, I'm glad to see it's fixed. Maybe I can get the admin to update this installation. I'm sure there's a few more fixes like this I'll wander into.

      -QM
      --
      Quantum Mechanics: The dreams stuff is made of

        Not to say that 5.8.0 was a bad release, but bumping up to at least 5.8.1 should bring you a bunch of bug fixes that crept into 5.8.0 release. Of course, the 5.8.2 release with patch above was released over four years ago.

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