[perl #77640] [PATCH] Math::BigInt->new($n)->bnok($k) incorrect for $k==0 and $k===$n-1

# New Ticket Created by  "Piotr Fusik" 
# Please include the string:  [perl #77640]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=77640 >


This is a bug report for perl from pfusik@op.pl,
generated with the help of perlbug 1.39 running under perl 5.12.1.


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There is a bug in Math::BigInt's implementation of n over k:
Math::BigInt->new($n)->bnok(0) is $n+1, should be 1.
Math::BigInt->new($n)->bnok($n-1) is 1, should be $n.

Attached is a patch.
I've fixed one test case and added new test cases.
I've corrected misleading comments, including one in Math::BigInt::Calc::_is_odd.

-----------------------------------------------------------------
---
Flags:
    category=library
    severity=medium
    module=Math::BigInt
---
Site configuration information for perl 5.12.1:

Configured by 1 at Thu Jul 29 16:39:48 2010.

Summary of my perl5 (revision 5 version 12 subversion 1) configuration:
   
  Platform:
    osname=MSWin32, osvers=5.1, archname=MSWin32-x86-multi-thread
    uname='Win32 strawberryperl 5.12.1.0 #1 Thu Jul 29 10:08:11 2010 i386'
    config_args='undef'
    hint=recommended, useposix=true, d_sigaction=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='gcc', ccflags =' -s -O2 -DWIN32 -DHAVE_DES_FCRYPT  -DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_SYS -fno-strict-aliasing -mms-bitfields -DPERL_MSVCRT_READFIX',
    optimize='-s -O2',
    cppflags='-DWIN32'
    ccversion='', gccversion='4.4.3', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='long long', lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='g++', ldflags ='-s -L"C:\bin\strawberry\perl\lib\CORE" -L"C:\bin\strawberry\c\lib"'
    libpth=C:\bin\strawberry\c\lib C:\bin\strawberry\c\i686-w64-mingw32\lib
    libs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
    perllibs=-lmoldname -lkernel32 -luser32 -lgdi32 -lwinspool -lcomdlg32 -ladvapi32 -lshell32 -lole32 -loleaut32 -lnetapi32 -luuid -lws2_32 -lmpr -lwinmm -lversion -lodbc32 -lodbccp32 -lcomctl32
    libc=, so=dll, useshrplib=true, libperl=libperl512.a
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-mdll -s -L"C:\bin\strawberry\perl\lib\CORE" -L"C:\bin\strawberry\c\lib"'

Locally applied patches:
    

---
@INC for perl 5.12.1:
    C:/bin/strawberry/perl/site/lib
    C:/bin/strawberry/perl/vendor/lib
    C:/bin/strawberry/perl/lib
    .

---
Environment for perl 5.12.1:
    CYGWIN=nodosfilewarning
    HOME=C:\Documents and Settings\Administrator
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
    PATH=C:\Program Files\ImageMagick-6.6.3-Q16;C:\bin;C:\bin\strawberry\perl\site\bin;C:\bin\strawberry\perl\bin;c:\bin\ruby\bin;C:\bin\nant\bin;C:\Program Files\GnuWin32\bin;C:\bin\ragel\bin;C:\bin\MinGW\bin;C:\bin\cygwin\bin;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\Program Files\Intel\DMIX;C:\Program Files\Intel\WiFi\bin\;C:\Program Files\Common Files\Roxio Shared\DLLShared\;C:\Program Files\Common Files\Roxio Shared\9.0\DLLShared\;C:\WINDOWS\Microsoft.NET\Framework\v4.0.30319;C:\Program Files\java\jdk1.6.0_10\bin;C:\Program Files\Microsoft SQL Server\100\Tools\Binn\;C:\Program Files\Microsoft SQL Server\100\DTS\Binn\;C:\Program Files\Microsoft SQL Server\100\Tools\Binn\VSShell\Common7\IDE\;C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\PrivateAssemblies\;C:\WINDOWS\system32\WindowsPowerShell\v1.0;C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE;C:\Program Files\Microsoft Visual Studio 9.0\VC\bin;C:\Program Files\Microsoft SDKs\Windows\v
 6.0A\bin;C:\bin\oracle\product\10.2.0\db_1\bin;C:\Program Files\7-Zip;C:\Program Files\VoiceAge\Common;C:\bin\MinGW\opt\mingw32ce\bin;C:\Program Files\TortoiseSVN\bin;C:\Program Files\Windows Installer XML v3\bin;C:\bin\flex_sdk\bin;C:\bin\apache-cxf-2.2.2\bin;C:\Program Files\MPlayer-1.0rc2;C:\bin\python\Scripts;C:\Program Files\Git\bin;C:\Program Files\RSA Security\RSA SecurID Software Token\;C:\bin\D\dmd\windows\bin;C:\bin\D\dmd2\windows\bin;C:\WINDOWS\system32\WindowsPowerShell\v1.0;C:\Program Files\FAIL\;C:\Program Files\TortoiseGit\bin;C:\bin\strawberry\c\bin
    PERL_BADLANG (unset)
    SHELL (unset)

• [perl #77640] [PATCH] Math::BigInt->new($n)->bnok($k) incorrect for $k==0 and $k===$n-1 by Piotr Fusik