[perl #27053] /^/m doesn't match after a newline at the end of the string

# New Ticket Created by  Zefram 
# Please include the string:  [perl #27053]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org:80/rt3/Ticket/Display.html?id=27053 >



This is a bug report for perl from zefram@fysh.org,
generated with the help of perlbug 1.34 running under perl v5.8.2.


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[Please enter your report here]

perlre(1):
#                               You may, however, wish to treat a string as a
#       multi-line buffer, such that the "^" will match after any newline
#       within the string, and "$" will match before any newline.  At the cost
#       of a little more overhead, you can do this by using the /m modifier on
#       the pattern match operator.

Test cases:
	perl -e 'print "\n" =~ /^\z/m ? "yes\n" : "no\n"'

Contrary to the documentation, /^/m does not match after a newline that
is at the end of the string.  For the code responsible, search for "case
BOL" in regexec.c.  This behaviour looks intentional, but I don't see
what the intent was.  I think this should behave as documented, with
/^/m matching after *any* newline or at the very beginning of the string.

[Please do not change anything below this line]
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---
Flags:
    category=core
    severity=medium
---
Site configuration information for perl v5.8.2:

Configured by Debian Project at Sat Nov 15 18:33:34 EST 2003.

Summary of my perl5 (revision 5.0 version 8 subversion 2) configuration:
  Platform:
    osname=linux, osvers=2.4.22-xfs+ti1211, archname=i386-linux-thread-multi
    uname='linux kosh 2.4.22-xfs+ti1211 #1 sat oct 25 10:11:37 est 2003 i686 gnulinux '
    config_args='-Dusethreads -Duselargefiles -Dccflags=-DDEBIAN -Dcccdlflags=-fPIC -Darchname=i386-linux -Dprefix=/usr -Dprivlib=/usr/share/perl/5.8.2 -Darchlib=/usr/lib/perl/5.8.2 -Dvendorprefix=/usr -Dvendorlib=/usr/share/perl5 -Dvendorarch=/usr/lib/perl5 -Dsiteprefix=/usr/local -Dsitelib=/usr/local/share/perl/5.8.2 -Dsitearch=/usr/local/lib/perl/5.8.2 -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.5.8.2 -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 -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O3',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBIAN -fno-strict-aliasing -I/usr/local/include'
    ccversion='', gccversion='3.3.2 (Debian)', 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-2.3.2.so, so=so, useshrplib=true, libperl=libperl.so.5.8.2
    gnulibc_version='2.3.2'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-rdynamic'
    cccdlflags='-fPIC', lddlflags='-shared -L/usr/local/lib'

Locally applied patches:
    

---
@INC for perl v5.8.2:
    /etc/perl
    /usr/local/lib/perl/5.8.2
    /usr/local/share/perl/5.8.2
    /usr/lib/perl5
    /usr/share/perl5
    /usr/lib/perl/5.8.2
    /usr/share/perl/5.8.2
    /usr/local/lib/site_perl
    .

---
Environment for perl v5.8.2:
    HOME=/home/zefram
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=/home/zefram/pub/i686-pc-linux-gnu/bin:/home/zefram/pub/common/bin:/usr/bin:/usr/X11R6/bin:/bin:/usr/local/bin:/usr/games:/opt/libunsn/bin
    PERL_BADLANG (unset)
    SHELL=/usr/bin/zsh

• [perl #27053] /^/m doesn't match after a newline at the end of the string by Zefram