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[perl #123553] perl5db.pl: Undefined subroutine &DB::db_warn called

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On Mon Jan 05 16:26:08 2015, choroba@cpan.org wrote:
> This is a bug report for perl from choroba@cpan.org,
> generated with the help of perlbug 1.39 running under perl 5.18.1.
> 
> 
> -----------------------------------------------------------------
> [Please describe your issue here]
> 
> Perl debugger sometimes tries to call a non-existent subroutine
> db_warn. It's real name is _db_warn, though.
> 
> How to replicate:
> 
> perl -d -e1
> !/
> 
> Output:
> 
> /bin/bash: /: Is a directory
> Undefined subroutine &DB::db_warn called at
> /usr/lib/perl5/5.18.1/perl5db.pl line 6740.
>   at /usr/lib/perl5/5.18.1/perl5db.pl line 6740.
>          DB::_db_system('/bin/bash', '-c', '/') called at
> /usr/lib/perl5/5.18.1/perl5db.pl line 3923
>          DB::Obj::_handle_sh_command('DB::Obj=HASH(0x105df48)') called
> at /usr/lib/perl5/5.18.1/perl5db.pl line 2992
>          DB::DB called at -e line 1
> 
> Patch to fix the issue attached.
> 
> Choroba
> 
Thank you very much for this report.  This is a bug which crept in somewhere between perl 5.16.3 and perl 5.18.2.
#####
[~] 11 $ perlbrew switch perl-5.16.3
[~] 12 $ perl -d -e1
Loading DB routines from perl5db.pl version 1.37
Editor support available.
Enter h or 'h h' for help, or 'man perldebug' for more help.
main::(-e:1):	1
  DB<1> !/
No such command!
  DB<1> q
[~] 13 $ perlbrew switch perl-5.18.2
[~] 14 $ perl -d -e1
Loading DB routines from perl5db.pl version 1.39_10
Editor support available.
Enter h or 'h h' for help, or 'man perldebug' for more help.
main::(-e:1):	1
  DB<1> !/
/bin/bash: /: Is a directory
Undefined subroutine &DB::db_warn called at /home/jkeenan/perl5/perlbrew/perls/perl-5.18.2/lib/5.18.2/perl5db.pl line 6735.
 at /home/jkeenan/perl5/perlbrew/perls/perl-5.18.2/lib/5.18.2/perl5db.pl line 6735.
	DB::_db_system('/bin/bash', '-c', '/') called at /home/jkeenan/perl5/perlbrew/perls/perl-5.18.2/lib/5.18.2/perl5db.pl line 3918
	DB::Obj::_handle_sh_command('DB::Obj=HASH(0x1dee6b0)') called at /home/jkeenan/perl5/perlbrew/perls/perl-5.18.2/lib/5.18.2/perl5db.pl line 2987
	DB::DB called at -e line 1
Debugged program terminated.  Use q to quit or R to restart,
use o inhibit_exit to avoid stopping after program termination,
h q, h R or h o to get additional info.
  DB<2> q
#####
We should figure out what commit broke this functionality, then consider whether we should apply your patch or try to restore the previous behavior.
> [Please do not change anything below this line]
> -----------------------------------------------------------------
> ---
> Flags:
>      category=library
>      severity=low
>      module=DB
> ---
> This perlbug was built using Perl 5.18.1 - Fri Sep 27 18:27:33 UTC
> 2013
> It is being executed now by  Perl 5.18.1 - Fri Sep 27 18:20:30 UTC
> 2013.
> 
> Site configuration information for perl 5.18.1:
> 
> Configured by abuild at Fri Sep 27 18:20:30 UTC 2013.
> 
> Summary of my perl5 (revision 5 version 18 subversion 1)
> configuration:
> 
> Platform:
>   osname=linux, osvers=3.4.6-2.10-xen, archname=x86_64-linux-thread-
> multi
>    uname='linux build16 3.4.6-2.10-xen #1 smp thu jul 26 09:36:26 utc
> 2012
> (641c197) x86_64 x86_64 x86_64 gnulinux '
>    config_args='-ds -e -Dprefix=/usr -Dvendorprefix=/usr
> -Dinstallusrbinperl
> -Dusethreads -Di_db -Di_dbm -Di_ndbm -Di_gdbm -Dd_dbm_open
> -Duseshrplib=true
> -Doptimize=-fmessage-length=0 -grecord-gcc-switches -O2 -Wall
> -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables
> -fasynchronous-unwind-tables -g -Wall -pipe -Accflags=-
> DPERL_USE_SAFE_PUTENV
> -Dotherlibdirs=/usr/lib/perl5/site_perl
> -Dinc_version_list=5.18.0/x86_64-linux-thread-multi 5.18.0'
>   hint=recommended, useposix=true, d_sigaction=define
>   useithreads=define, usemultiplicity=define
>   useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
>   use64bitint=define, use64bitall=define, uselongdouble=undef
>   usemymalloc=n, bincompat5005=undef
> Compiler:
>    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE
> -DPERL_USE_SAFE_PUTENV
> -fno-strict-aliasing -pipe -fstack-protector -D_LARGEFILE_SOURCE
> -D_FILE_OFFSET_BITS=64',
>    optimize='-fmessage-length=0 -grecord-gcc-switches -O2 -Wall
> -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables
> -fasynchronous-unwind-tables -g -Wall -pipe',
>    cppflags='-D_REENTRANT -D_GNU_SOURCE -DPERL_USE_SAFE_PUTENV
> -fno-strict-aliasing -pipe -fstack-protector'
>    ccversion='', gccversion='4.8.1 20130909 [gcc-4_8-branch revision
> 202388]', gccosandvers=''
>   intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
>   d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
>    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t',
> lseeksize=8
>   alignbytes=8, prototype=define
> Linker and Libraries:
>   ld='cc', ldflags =' -L/usr/local/lib64 -fstack-protector'
>   libpth=/lib64 /usr/lib64 /usr/local/lib64
>   libs=-lm -ldl -lcrypt -lpthread
>   perllibs=-lm -ldl -lcrypt -lpthread
>   libc=/lib64/libc-2.18.so, so=so, useshrplib=true, libperl=libperl.so
>   gnulibc_version='2.18'
> Dynamic Linking:
>    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E
> -Wl,-rpath,/usr/lib/perl5/5.18.1/x86_64-linux-thread-multi/CORE'
>    cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib64
> -fstack-protector'
> 
> Locally applied patches:
> 
> 
> ---
> @INC for perl 5.18.1:
>      /home/choroba/perl5/lib/perl5/x86_64-linux-thread-multi
>      /home/choroba/perl5/lib/perl5/x86_64-linux-thread-multi
>      /home/choroba/perl5/lib/perl5
>      /home/choroba/perl5/lib/perl5/x86_64-linux-thread-multi
>      /home/choroba/perl5/lib/perl5/x86_64-linux-thread-multi
>      /home/choroba/perl5/lib/perl5
>      /usr/lib/perl5/site_perl/5.18.1/x86_64-linux-thread-multi
>      /usr/lib/perl5/site_perl/5.18.1
>      /usr/lib/perl5/vendor_perl/5.18.1/x86_64-linux-thread-multi
>      /usr/lib/perl5/vendor_perl/5.18.1
>      /usr/lib/perl5/5.18.1/x86_64-linux-thread-multi
>      /usr/lib/perl5/5.18.1
>      /usr/lib/perl5/site_perl
>      .
> 
> ---
> Environment for perl 5.18.1:
>      HOME=/home/choroba
>      LANG=en_US.UTF-8
>      LANGUAGE=en_US.utf8
>      LD_LIBRARY_PATH (unset)
>      LOGDIR (unset)
> 
> PATH=/home/choroba/perl5/bin:/home/choroba/bin:/bin:/sbin:/usr/bin:/usr/local/bin:/usr/games:/usr/X11R6/bin:/opt/gnome/bin:/home/choroba/perl/bin:.
> 
> PERL5LIB=/home/choroba/perl5/lib/perl5/x86_64-linux-thread-
> multi:/home/choroba/perl5/lib/perl5:/home/choroba/perl5/lib/perl5/x86_64-
> linux-thread-multi:/home/choroba/perl5/lib/perl5:
>      PERL_BADLANG (unset)
>      PERL_LOCAL_LIB_ROOT=/home/choroba/perl5
>      PERL_MB_OPT=--install_base /home/choroba/perl5
>      PERL_MM_OPT=INSTALL_BASE=/home/choroba/perl5
>      SHELL=/bin/bash
-- 
James E Keenan (jkeenan@cpan.org)
---
via perlbug:  queue: perl5 status: new
https://rt.perl.org/Ticket/Display.html?id=123553

Thread Previous

• [perl #123553] perl5db.pl: Undefined subroutine &DB::db_warn called by E . Choroba
• [perl #123553] perl5db.pl: Undefined subroutine &DB::db_warn called by Father Chrysostomos via RT
• [perl #123553] perl5db.pl: Undefined subroutine &DB::db_warn called by James E Keenan via RT