Re: [perl #75758] Perl print error to STDERR, but finish with error status 0

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

27e904532594b7fb224bdf9a05bf3b5336b8a39e is first bad commit
commit 27e904532594b7fb224bdf9a05bf3b5336b8a39e
Author: David Mitchell <[email protected]>
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