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# New Ticket Created by Fitz Elliott
# Please include the string: [perl #39141]
# in the subject line of all future correspondence about this issue.
# <URL: https://rt.perl.org/rt3/Ticket/Display.html?id=39141 >


Hello,

When diagnostics is in use, calling warn() or die() with a string
consiting of only newlines will cause perl to print lots of warnings.

$ perl -e 'use diagnostics; warn "\n";'
Use of uninitialized value in substitution (s///) at
/usr/share/perl/5.8/diagnostics.pm line 576.
Use of uninitialized value in study at (eval 1) line 3.
Use of uninitialized value in substitution (s///) at (eval 1) line 4.
Use of uninitialized value in substitution (s///) at (eval 1) line 7.
Use of uninitialized value in substitution (s///) at (eval 1) line 10.
Use of uninitialized value in substitution (s///) at (eval 1) line 13.
Use of uninitialized value in substitution (s///) at (eval 1) line 16.
Use of uninitialized value in substitution (s///) at (eval 1) line 19.
Use of uninitialized value in substitution (s///) at (eval 1) line 22.
[snip]
$

This is true for any number of newlines. Any non-newline character in the
string will make the diagnostics perform as expected.

$ perl -e 'use diagnostics; warn "\r\n";'

$

Perhaps the 'return unless defined' in splainthis() (shown below) should
not be commented out?

sub splainthis {
return 0 if $TRACEONLY;
local $_ = shift;
local $\;
### &finish_compilation unless %msg;
s/\.?\n+$//;
my $orig = $_;
# return unless defined;

[snip]



Cheers,
Fitz



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

Configured by Debian Project at Tue Apr 4 22:34:25 UTC 2006.

Summary of my perl5 (revision 5 version 8 subversion 8) configuration:
Platform:
osname=linux, osvers=2.6.15.4, archname=i486-linux-gnu-thread-multi
uname='linux ninsei 2.6.15.4 #1 smp preempt mon feb 20 09:48:53 pst
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='4.0.3 (Debian 4.0.3-1)', 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
/usr/local/lib/perl/5.8.7
/usr/local/share/perl/5.8.7
/usr/local/lib/perl/5.8.4
/usr/local/share/perl/5.8.4
/usr/local/lib/perl/5.8.3
/usr/local/share/perl/5.8.3
/usr/local/lib/perl/5.8.2
/usr/local/share/perl/5.8.2
.

---
Environment for perl v5.8.8:
HOME=/home/felliott
LANG=en_US.UTF-8
LANGUAGE (unset)
LD_LIBRARY_PATH (unset)
LOGDIR (unset)

PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games:/home/felliott/bin
PERL_BADLANG (unset)
SHELL=/bin/bash

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  • Dave Mitchell at May 19, 2006 at 12:17 am

    On Mon, May 15, 2006 at 12:46:59PM -0700, Fitz Elliott wrote:
    When diagnostics is in use, calling warn() or die() with a string
    consiting of only newlines will cause perl to print lots of warnings.

    $ perl -e 'use diagnostics; warn "\n";'
    Use of uninitialized value in substitution (s///) at
    /usr/share/perl/5.8/diagnostics.pm line 576.
    Use of uninitialized value in study at (eval 1) line 3.
    Use of uninitialized value in substitution (s///) at (eval 1) line 4.
    Use of uninitialized value in substitution (s///) at (eval 1) line 7.
    Use of uninitialized value in substitution (s///) at (eval 1) line 10.
    Use of uninitialized value in substitution (s///) at (eval 1) line 13.
    Use of uninitialized value in substitution (s///) at (eval 1) line 16.
    Use of uninitialized value in substitution (s///) at (eval 1) line 19.
    Use of uninitialized value in substitution (s///) at (eval 1) line 22.
    [snip]
    $

    This is true for any number of newlines. Any non-newline character in the
    string will make the diagnostics perform as expected.

    $ perl -e 'use diagnostics; warn "\r\n";'

    $

    Perhaps the 'return unless defined' in splainthis() (shown below) should
    not be commented out?

    sub splainthis {
    return 0 if $TRACEONLY;
    local $_ = shift;
    local $\;
    ### &finish_compilation unless %msg;
    s/\.?\n+$//;
    my $orig = $_;
    # return unless defined;
    thansk for the report. I';ve fixed this in the developement version of
    perl with the change below; simjilar to, but not quite what you suggest.

    --
    A power surge on the Bridge is rapidly and correctly diagnosed as a faulty
    capacitor by the highly-trained and competent engineering staff.
    -- Things That Never Happen in "Star Trek" #9

    Change 28231 by davem@davem-splatty on 2006/05/19 00:14:15

    [perl #39141] lots of warnings with diagnostics and (warn or die)
    stop C<use diagnostics; warn "\n"> outputing lots of 'uninit'
    warnings.

    Affected files ...

    ... //depot/perl/lib/diagnostics.pm#39 edit

    Differences ...

    ==== //depot/perl/lib/diagnostics.pm#39 (xtext) ====

    @@ -562,6 +562,7 @@
    # but be aware of messsages containing " at this-or-that"
    my $real = 0;
    my @secs = split( / at / );
    + return unless @secs;
    $_ = $secs[0];
    for my $i ( 1..$#secs ){
    if( $secs[$i] =~ /.+? (?:line|chunk) \d+/ ){

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postedMay 15, '06 at 7:48p
activeMay 19, '06 at 12:17a
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