die() and encodings on stderr => segfault

# New Ticket Created by  "Matthias Urlichs" 
# Please include the string:  [perl #46327]
# in the subject line of all future correspondence about
this issue. 
# <URL: h
ttp://rt.perl.org/rt3/Ticket/Display.html?id=46327 >



This is a bug report for perl from smurfnoris.de,
generated with the help of perlbug 1.35 running under perl
v5.8.8.


------------------------------------------------------------
-----
[Please enter your report here]

... or, how to segfault perl in two lines of code:

#!/usr/bin/perl

#use utf8; # does not fix the problem
binmode(STDERR,":encoding(latin1)"); # required
for segfault
binmode(STDOUT,":encoding(latin1)"); # not
required for fault

print "374";  # works; that's a German u-umlaut
die "374";    # segfaults


[Please do not change anything below this line]
------------------------------------------------------------
-----
---
Flags:
    category=core
    severity=medium
---
Site configuration information for perl v5.8.8:

Configured by Debian Project at Wed Dec  6 23:17:41 UTC
2006.

Summary of my perl5 (revision 5 version 8 subversion 8)
configuration:
  Platform:
    osname=linux, osvers=2.6.18.3,
archname=i486-linux-gnu-thread-multi
    uname='linux saens 2.6.18.3 #1 smp sat nov 25 13:39:52
est 2006 i686 gnulinux '
    config_args='-Dusethreads -Duselargefiles
-Dccflags=-DDEBIAN -Dcccdlflags=-fPIC
-Darchname=i486-linux-gnu -Dprefix=/usr
-Dprivlib=/usr/share/perl/5.8 -Darchlib=/usr/lib/perl/5.8
-Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5
-Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local
-Dsitelib=/usr/local/share/perl/5.8.8
-Dsitearch=/usr/local/lib/perl/5.8.8
-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 -Uusesfio -Uusenm -Duseshrplib
-Dlibperl=libperl.so.5.8.8 -Dd_dosuid -des'
    hint=recommended, useposix=true, d_sigaction=define
    usethreads=define use5005threads=undef
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
-DTHREADS_HAVE_PIDS -DDEBIAN -fno-strict-aliasing -pipe
-I/usr/local/include -D_LARGEFILE_SOURCE
-D_FILE_OFFSET_BITS=64',
    optimize='-O2',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS
-DDEBIAN -fno-strict-aliasing -pipe -I/usr/local/include'
    ccversion='', gccversion='4.1.2 20061115 (prerelease)
(Debian 4.1.1-20)', 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 =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lgdbm -lgdbm_compat -ldb -ldl -lm -lpthread -lc
-lcrypt
    perllibs=-ldl -lm -lpthread -lc -lcrypt
    libc=/lib/libc-2.3.6.so, so=so, useshrplib=true,
libperl=libperl.so.5.8.8
    gnulibc_version='2.3.6'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef,
ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared
-L/usr/local/lib'

Locally applied patches:
    

---
INC
for perl v5.8.8:
    /etc/perl
    /usr/local/lib/perl/5.8.8
    /usr/local/share/perl/5.8.8
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.8
    /usr/share/perl/5.8
    /usr/local/lib/site_perl
    .

---
Environment for perl v5.8.8:
    HOME=/home/smurf
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LC_ALL=en_US.UTF-8
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
   
PATH=/home/smurf/bin:/usr/local/bin:/usr/bin:/bin:/usr/bin/X
11:/usr/games:/usr/pop/bin:/pop/technik/bin:/usr/X11R6/bin
    PERL_BADLANG (unset)
    SHELL=/bin/bash

"Matthias Urlichs" (via RT)
<perlbug-followupperl.org> writes:

> # New Ticket Created by  "Matthias Urlichs" 
> # Please include the string:  [perl #46327]
> # in the subject line of all future correspondence
about this issue. 
> # <URL: h
ttp://rt.perl.org/rt3/Ticket/Display.html?id=46327 >
> 
> 
> 
> This is a bug report for perl from smurfnoris.de,
> generated with the help of perlbug 1.35 running under
perl v5.8.8.
> 
> 
>
------------------------------------------------------------
-----
> [Please enter your report here]
> 
> ... or, how to segfault perl in two lines of code:
> 
> #!/usr/bin/perl
> 
> #use utf8; # does not fix the problem
> binmode(STDERR,":encoding(latin1)"); #
required for segfault
> binmode(STDOUT,":encoding(latin1)"); # not
required for fault
> 
> print "374";  # works; that's a German
u-umlaut
> die "374";    # segfaults
> 
> 
> [Please do not change anything below this line]
>
------------------------------------------------------------
-----

If you need a workaround, then try to upgrade the warn/die
string to
have a utf8 flag:

$ perl -e
'binmode(STDERR,":encoding(latin1)");$x="374
";utf8::upgrade($x); die $x'
ü at -e line 1.

The segfault does not occur in perl5.10.0 anymore (since
patch
#30213), but the output looks somewhat ugly:

$ perl5.10.0 -e
'binmode(STDERR,":encoding(latin1)");$x="374
";die $x'
xe line 1.

For a real fix it seems to me that the Perl interna need a
SV version
of Perl_write_to_stderr() which makes sure that
PERL_WRITE_MSG_TO_CONSOLE gets a utf8-encoded character
string.

Regards,
        Slaven

-- 
Slaven Rezic - slaven <at> rezic <dot> de

Tk-AppMaster: a perl/Tk module launcher designed for
handhelds
	http://tk-appmaster.sf.net