[perl #122443] Failure to debug programs using threads::shared in 5.18.2

# New Ticket Created by  Christian Stahlhut 
# Please include the string:  [perl #122443]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=122443 >


Hi!

I recently switched from Perl version 5.16.3 to 5.18.2 and debugging any program which uses threads::shared is no longer possible for me.

Calling the attached program via 'perl -d ./debug-me.pl' now causes the debugger to fail with the following message:
-----
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.

lock can only be used on shared values at /usr/lib64/perl5/5.18.2/perl5db.pl line 4100.
BEGIN failed--compilation aborted at ./debug-me.pl line 4.
lock can only be used on shared values at /usr/lib64/perl5/5.18.2/perl5db.pl line 2510.
END failed--call queue aborted at ./debug-me.pl line 4.
Unbalanced scopes: 3 more ENTERs than LEAVEs
-----

So to me there seems to be a (newly introduced) bug in the perl-debugger's core.


Summary of my perl5 (revision 5 version 18 subversion 2) configuration:
   
  Platform:
    osname=linux, osvers=3.12.21-gentoo-r1, archname=x86_64-linux-thread-multi
    uname='linux azmodan 3.12.21-gentoo-r1 #1 smp fri jun 6 23:37:17 cest 2014 x86_64 intel(r) core(tm) i5-3570k cpu @ 3.40ghz genuineintel gnulinux '
    config_args='-des -Duseshrplib -Darchname=x86_64-linux-thread -Dcc=x86_64-pc-linux-gnu-gcc -Doptimize=-O2 -march=native -pipe -Dldflags=-Wl,-O1 -Wl,--as-needed -Dprefix=/usr -Dinstallprefix=/usr -Dsiteprefix=/usr/local -Dvendorprefix=/usr -Dscriptdir=/usr/bin -Dprivlib=/usr/lib64/perl5/5.18.2 -Darchlib=/usr/lib64/perl5/5.18.2/x86_64-linux-thread-multi -Dsitelib=/usr/local/lib64/perl5/5.18.2 -Dsitearch=/usr/local/lib64/perl5/5.18.2/x86_64-linux-thread-multi -Dvendorlib=/usr/lib64/perl5/vendor_perl/5.18.2 -Dvendorarch=/usr/lib64/perl5/vendor_perl/5.18.2/x86_64-linux-thread-multi -Dman1dir=/usr/share/man/man1 -Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1 -Dsiteman3dir=/usr/local/man/man3 -Dvendorman1dir=/usr/share/man/man1 -Dvendorman3dir=/usr/share/man/man3 -Dman1ext=1 -Dman3ext=3pm -Dlibperl=libperl.so.5.18.2 -Dlocincpth=/usr/include  -Dglibpth=/lib64 /usr/lib64  -Duselargefiles -Dd_semctl_semun -Dcf_by=Gentoo -Dmyhostname=localhost -Dperladmin=root@local
 host -Dinstallusrbinperl=n -Ud_csh -Uusenm -Di_ndbm -Di_gdbm -Di_db -Dusethreads -DDEBUGGING=none -Dinc_version_list=5.18.0/x86_64-linux-thread-multi 5.18.0 5.18.1/x86_64-linux-thread-multi 5.18.1  -Dlibpth=/usr/local/lib64 /lib64 /usr/lib64 -Dnoextensions=ODBM_File'
    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='x86_64-pc-linux-gnu-gcc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2 -march=native -pipe',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe'
    ccversion='', gccversion='4.7.3', 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='x86_64-pc-linux-gnu-gcc', ldflags ='-Wl,-O1 -Wl,--as-needed'
    libpth=/usr/local/lib64 /lib64 /usr/lib64
    libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lpthread -lc -lgdbm_compat
    perllibs=-lnsl -ldl -lm -lcrypt -lutil -lpthread -lc
    libc=/lib/libc-2.19.so, so=so, useshrplib=true, libperl=libperl.so.5.18.2
    gnulibc_version='2.19'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -march=native -pipe -Wl,-O1 -Wl,--as-needed'


Characteristics of this binary (from libperl): 
  Compile-time options: HAS_TIMES MULTIPLICITY PERLIO_LAYERS
                        PERL_DONT_CREATE_GVSV
                        PERL_HASH_FUNC_ONE_AT_A_TIME_HARD
                        PERL_IMPLICIT_CONTEXT PERL_MALLOC_WRAP
                        PERL_PRESERVE_IVUV PERL_SAWAMPERSAND USE_64_BIT_ALL
                        USE_64_BIT_INT USE_ITHREADS USE_LARGE_FILES
                        USE_LOCALE USE_LOCALE_COLLATE USE_LOCALE_CTYPE
                        USE_LOCALE_NUMERIC USE_PERLIO USE_PERL_ATOF
                        USE_REENTRANT_API
  Locally applied patches:
	gentoo/EUMM-RUNPATH - https://bugs.gentoo.org/105054 cpan/ExtUtils-MakeMaker: drop $PORTAGE_TMPDIR from LD_RUN_PATH
	gentoo/EUMM_delete_packlist - Don't install .packlist or perllocal.pod for perl or vendor
	gentoo/config_over - Remove -rpath and append LDFLAGS to lddlflags
	gentoo/cpan_definstalldirs - Provide a sensible INSTALLDIRS default for modules installed from CPAN.
	gentoo/cpanplus_definstalldirs - Configure CPANPLUS to use the site directories by default.
	gentoo/create_libperl_soname - https://bugs.gentoo.org/286840 Set libperl soname
	gentoo/drop_fstack_protector - https://bugs.gentoo.org/348557 Don't force -fstack-protector on everyone.
	gentoo/enc2xs - Tweak enc2xs to follow symlinks and ignore missing @INC directories.
	gentoo/mod_paths - Add /etc/perl to @INC
	gentoo/patchlevel - List packaged patches for perl-5.18.2-r1(#2) in patchlevel.h
	gentoo/aix_soname - aix gcc detection and shared library soname support
	gentoo/opensolars_headers - Add headers for opensolaris
	gentoo/cleanup-paths - Cleanup PATH and shrpenv
	gentoo/usr_local - Remove /usr/local paths
	gentoo/hints_hpux - Fix hpux hints
	gentoo/darwin-cc-ld - https://bugs.gentoo.org/297751 darwin: Use $CC to link
	gentoo/interix - Fix interix hints
	fixes/net_smtp_docs - [rt.cpan.org #36038] Document the Net::SMTP 'Port' option
	debian/cpan-missing-site-dirs - Fix CPAN::FirstTime defaults with nonexisting site dirs if a parent is writable
	fixes/memoize_storable_nstore - [rt.cpan.org #77790] Memoize::Storable: respect 'nstore' option not respected
	fixes/net_ftp_failed_command - [rt.cpan.org #37700] Net::FTP: cope gracefully with a failed command
	fixes/perlbug-patchlist - [3541c11] [perl #118433] Make perlbug look up the list of local patches at run time
	fixes/module_metadata_taint_fix - [bff978f] [rt.cpan.org #88576] untaint version, if needed, in Module::Metadata
	fixes/IPC-SysV-spelling - [rt.cpan.org #86736] Fix spelling of IPC_CREAT in IPC-SysV documentation
	fixes/freemint -
  Built under linux
  Compiled at Jul 30 2014 12:58:24
  @INC:
    /etc/perl
    /usr/local/lib64/perl5/5.18.2/x86_64-linux-thread-multi
    /usr/local/lib64/perl5/5.18.2
    /usr/lib64/perl5/vendor_perl/5.18.2/x86_64-linux-thread-multi
    /usr/lib64/perl5/vendor_perl/5.18.2
    /usr/local/lib64/perl5
    /usr/lib64/perl5/vendor_perl
    /usr/lib64/perl5/5.18.2/x86_64-linux-thread-multi
    /usr/lib64/perl5/5.18.2
    .

• [perl #122443] Failure to debug programs using threads::shared in 5.18.2 by Christian Stahlhut via RT
• [perl #122443] Failure to debug programs using threads::shared in 5.18.2 by James E Keenan via RT
• [perl #122443] Failure to debug programs using threads::shared in 5.18.2 by Christian Stahlhut