NaNcytyping appears to have regressed and broken again in 5.8.8

# New Ticket Created by  Jesse Vincent 
# Please include the string:  [perl #41645]
# in the subject line of all future correspondence about
this issue. 
# <URL: h
ttp://rt.perl.org/rt3/Ticket/Display.html?id=41645 >



This is a bug report for perl from jessebestpractical.com,
generated with the help of perlbug 1.35 running under perl
v5.8.7.


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


Last night, I was chatting with a pythonista friend of mine
who cracked a joke about how poorly 5.6 worked, using as his
example "nancytyping." (0 + "Nancy" 
numifies to "NaN").

He admitted that this had been fixed for 5.8.x or so.  As I
was playing around, I discovered that 

1) Yes, it had been fixed, at least by 5.8.4..and appears to
have stayed fixed though 5.8.7

2) It appears to have broken again for 5.8.8 and a recent
blead.

3) There are no tests for it. The following testfile should
probably get added to core:


#!./perl

BEGIN {
    chdir 't' if -d 't';
    INC = '../lib';
}

use strict;
use warnings;

use Test::More tests => 2;
{
no warnings;

# 5.6 and 5.8.8 and newer appear to treat "Nancy"
as "NaN", leading to 
# some very wrong coercion

is (0+"Nancy", 0);
is (0+"Fred", 0);
}




[Please do not change anything below this line]
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---
Flags:
    category=core
    severity=medium
---
Site configuration information for perl v5.8.7:

Configured by Debian Project at Thu Dec 15 17:30:10 UTC
2005.

Summary of my perl5 (revision 5 version 8 subversion 7)
configuration:
  Platform:
    osname=linux, osvers=2.6.14.3,
archname=i486-linux-gnu-thread-multi
    uname='linux ninsei 2.6.14.3 #1 smp preempt mon nov 28
19:51:50 pst 2005 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/5.8.7
-Dsitearch=/usr/local/lib/perl/5.8.7
-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.5.8.7 -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 20051201 (prerelease)
(Debian 4.0.2-5)', 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-2.3.5.so, so=so, useshrplib=true,
libperl=libperl.so.5.8.7
    gnulibc_version='2.3.5'
  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:
    SPRINTF0 - fixes for sprintf formatting issues -
CVE-2005-3962

---
INC
for perl v5.8.7:
    /etc/perl
    /usr/local/lib/perl/5.8.7
    /usr/local/share/perl/5.8.7
    /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/5.8.4
    /usr/local/share/perl/5.8.4
    .

---
Environment for perl v5.8.7:
    HOME=/home/jesse
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
   
PATH=/usr/local/bin:/usr/bin:/bin:/usr/bin/X11:/usr/games
    PERL_BADLANG (unset)
    SHELL=/bin/bash

Jesse Vincent wrote:
> Last night, I was chatting with a pythonista friend of
mine who cracked a
> joke about how poorly 5.6 worked, using as his example
"nancytyping." (0 +
> "Nancy"  numifies to "NaN").
>
> He admitted that this had been fixed for 5.8.x or so. 
As I was playing
> around, I discovered that
>
> 1) Yes, it had been fixed, at least by 5.8.4..and
appears to have stayed
> fixed though 5.8.7
>
> 2) It appears to have broken again for 5.8.8 and a
recent blead.
>
> 3) There are no tests for it. The following testfile
should probably get
> added to core:

To me, 0+"Nancy" being NaN is consistent with how
numeric values are treated
in general; it's not much different from
0+"123beer" being 123.