Perl print error to STDERR, but finish with error status 0

[p5pRT]

Migrated from rt.perl.org#75758 (status was 'resolved')

Searchable as RT75758$

[p5pRT]

From [email protected]

Created by [email protected]

This is a bug report for perl from q@​cono.org.ua,
generated with the help of perlbug 1.39 running under perl 5.10.1.

-----------------------------------------------------------------
This code​:
perl -e'\sort{eval$;}%!' && echo "exit 0"
prints​: "panic​: restartop" into STDERR and finish with exit status 0

This code​:
perl -e'/(?{"})/' && echo "exit 0"
prints​: "panic​: top_env" into STDERR and finish with exit status 0

Perl Info

Flags:
    category=core
    severity=high

Site configuration information for perl 5.10.1:

Configured by Debian Project at Fri Apr 23 07:59:14 UTC 2010.

Summary of my perl5 (revision 5 version 10 subversion 1) configuration:

  Platform:
    osname=linux, osvers=2.6.24-27-server, archname=i486-linux-gnu-thread-multi
    uname='linux vernadsky 2.6.24-27-server #1 smp fri mar 12 01:45:06
utc 2010 i686 gnulinux '
    config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN
-Dcccdlflags=-fPIC -Darchname=i486-linux-gnu -Dprefix=/usr
-Dprivlib=/usr/share/perl/5.10 -Darchlib=/usr/lib/perl/5.10
-Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5
-Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local
-Dsitelib=/usr/local/share/perl/5.10.1
-Dsitearch=/usr/local/lib/perl/5.10.1 -Dman1dir=/usr/share/man/man1
-Dman3dir=/usr/share/man/man3 -Dsiteman1dir=/usr/local/man/man1
-Dsiteman3dir=/usr/local/man/man3 -Dman1ext=1 -Dman3ext=3perl
-Dpager=/usr/bin/sensible-pager -Uafs -Ud_csh -Ud_ualarm -Uusesfio
-Uusenm -DDEBUGGING=-g -Doptimize=-O2 -Duseshrplib
-Dlibperl=libperl.so.5.10.1 -Dd_dosuid -des'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=define, usemultiplicity=define
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=undef, use64bitall=undef, uselongdouble=undef
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='cc', ccflags ='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN
-fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2 -g',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DDEBIAN -fno-strict-aliasing
-pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.4.3', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',
lseeksize=8
    alignbytes=4, prototype=define
  Linker and Libraries:
    ld='cc', ldflags =' -fstack-protector -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib /usr/lib64
    libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc -lcrypt
    perllibs=-ldl -lm -lpthread -lc -lcrypt
    libc=/lib/libc-2.11.1.so, so=so, useshrplib=true, libperl=libperl.so.5.10.1
    gnulibc_version='2.11.1'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -O2 -g -L/usr/local/lib
-fstack-protector'

Locally applied patches:



@INC for perl 5.10.1:
    /etc/perl
    /usr/local/lib/perl/5.10.1
    /usr/local/share/perl/5.10.1
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.10
    /usr/share/perl/5.10
    /usr/local/lib/site_perl
    .


Environment for perl 5.10.1:
    HOME=/home/cono
    LANG=en_US.utf8
    LANGUAGE (unset)
    LC_ALL=en_US.UTF-8
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/cono/work/rakudo/parrot_install/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin:/usr/X11R6/bin:/home/cono/bin:.
    PERL_BADLANG (unset)
    SHELL=/usr/bin/zsh

-- 
Varyanick I. Alex
icq: 102 575 440
skype: cono..
[email protected]

[p5pRT]

From @nwc10

On Tue, Jun 15, 2010 at 03​:00​:08AM -0700, Alex Varyanick wrote​:

Thanks for the report.

This code​:
perl -e'\sort{eval$;}%!' && echo "exit 0"
prints​: "panic​: restartop" into STDERR and finish with exit status 0

That turns out to already be fixed in blead. I bisected with

#!/bin/sh
git clean -dxf
# If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line
# if Encode is not needed for the test, you can speed up the bisect by
# excluding it from the runs with -Dnoextensions=Encode
sh Configure -des -Dusedevel -Uusethreads -Doptimize="-Os" -Dcc=ccache\ gcc -Dld=gcc -Dnoextensions=Encode
test -f config.sh || exit 125
# Correct makefile for newer GNU gcc
perl -ni -we 'print unless /<(?​:built-in|command)/' makefile x2p/makefile
# if you just need miniperl, replace test_prep with miniperl
make -j4 test_prep
[ -x ./perl ] || exit 125
./perl -Ilib -e'\sort{eval$;}%!' 2>&1 | grep panic
ret=$?
[ $ret -gt 127 ] && ret=127
git clean -dxf

and it reveals that the fix was

27e9045 is first bad commit
commit 27e9045
Author​: David Mitchell <davem@​iabyn.com>
Date​: Thu Apr 8 13​:16​:56 2010 +0100

  fix RT 23810​: eval and tied methods
 
  Something like the following ended up corrupted​:
  sub FETCH { eval 'BEGIN{syntax err}' }
  The croak on error popped back the context stack etc to the EVAL pushed by
  entereval, but the corresponding JUMPENV_PUSH(3) unwound all the way to the
  outer perl_run, losing all the mg_get() related parts of the C stack.
 
  It turns out that the run-time parts of pp_entereval were protected with
  a new JUMPENV level, but the compile-time parts weren't. Add this.

:100644 100644 80c7b221d7e967a6f3380d70917bd73700b16852 bbb2d1587cb197977c996ecfe8abddf4f9aa3631 M pp_ctl.c
:040000 040000 7fa8480b6084b533c3eaddbbbd6834e2551f8a4e f2ec8022695df42cff76ab78c117bd44d1fb626c M t
bisect run success

I don't have a 5.12 handy, but I think from the timing that that fix isn't
in 5.12

This code​:
perl -e'/(?{"})/' && echo "exit 0"
prints​: "panic​: top_env" into STDERR and finish with exit status 0

This is still a bug in blead.

Nicholas Clark

[p5pRT]

The RT System itself - Status changed from 'new' to 'open'

[p5pRT]

From @Abigail

On Wed, Jun 16, 2010 at 01​:16​:08PM +0100, Nicholas Clark wrote​:

On Tue, Jun 15, 2010 at 03​:00​:08AM -0700, Alex Varyanick wrote​:

Thanks for the report.

This code​:
perl -e'\sort{eval$;}%!' && echo "exit 0"
prints​: "panic​: restartop" into STDERR and finish with exit status 0

That turns out to already be fixed in blead. I bisected with

#!/bin/sh
git clean -dxf
# If you can use ccache, add -Dcc=ccache\ gcc -Dld=gcc to the Configure line
# if Encode is not needed for the test, you can speed up the bisect by
# excluding it from the runs with -Dnoextensions=Encode
sh Configure -des -Dusedevel -Uusethreads -Doptimize="-Os" -Dcc=ccache\ gcc -Dld=gcc -Dnoextensions=Encode
test -f config.sh || exit 125
# Correct makefile for newer GNU gcc
perl -ni -we 'print unless /<(?​:built-in|command)/' makefile x2p/makefile
# if you just need miniperl, replace test_prep with miniperl
make -j4 test_prep
[ -x ./perl ] || exit 125
./perl -Ilib -e'\sort{eval$;}%!' 2>&1 | grep panic
ret=$?
[ $ret -gt 127 ] && ret=127
git clean -dxf

and it reveals that the fix was

27e9045 is first bad commit
commit 27e9045
Author​: David Mitchell <davem@​iabyn.com>
Date​: Thu Apr 8 13​:16​:56 2010 +0100

fix RT 23810​: eval and tied methods

Something like the following ended up corrupted​:
    sub FETCH \{ eval 'BEGIN\{syntax err\}' \}
The croak on error popped back the context stack etc to the EVAL pushed by
entereval\, but the corresponding JUMPENV\_PUSH\(3\) unwound all the way to the
outer perl\_run\, losing all the mg\_get\(\) related parts of the C stack\.

It turns out that the run\-time parts of pp\_entereval were protected with
a new JUMPENV level\, but the compile\-time parts weren't\. Add this\.

:100644 100644 80c7b221d7e967a6f3380d70917bd73700b16852 bbb2d1587cb197977c996ecfe8abddf4f9aa3631 M pp_ctl.c
:040000 040000 7fa8480b6084b533c3eaddbbbd6834e2551f8a4e f2ec8022695df42cff76ab78c117bd44d1fb626c M t
bisect run success

I don't have a 5.12 handy, but I think from the timing that that fix isn't
in 5.12

Indeed, it still is an issue in 5.12.1.

This code​:
perl -e'/(?{"})/' && echo "exit 0"
prints​: "panic​: top_env" into STDERR and finish with exit status 0

This is still a bug in blead.

Some additional diagnostic​:

  $ perl -e'/(?{"})/'
  panic​: top_env
  perl​: perl.c​:542​: perl_destruct​: Assertion `PL_scopestack_ix == 1' failed.
  Aborted
  $

which is exactly the same error "perl -e'\sort{eval$;}%!'" gives me in 5.12.1.

Abigail

[p5pRT]

@iabyn - Status changed from 'open' to 'resolved'