[perl #42614] NAN_COMPARE_BROKEN.DIV_BY_NAN_BUG (with patch)

# New Ticket Created by  patrick.dugnolle@bnpparibas.com 
# Please include the string:  [perl #42614]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=42614 >


Hi,

using the latest devel perl which is correcting the NAN_COMPARE_BROKEN bug 
solved by Jan Dubois on Win32/MSVC6, I came accross the following bug:

perl -MPOSIX -e "print 1.0/pow(-1,0.5)" 

would trigger an "Illegal division by zero" error, instead of outputing 
"-1.#IND" (the string representation of NaN on Win32)

It appears that changes #27576 and #27577 introducing NAN_COMPARE_BROKEN 
are incomplete and need the following addendum

*** perl-5.9.4/pp.c     Tue Aug 15 14:37:41 2006
--- perl-5.9.4/pp.c     Thu Apr 19 14:29:22 2007
***************
*** 1276,1284 ****
      } /* right wasn't SvIOK */
  #endif /* PERL_TRY_UV_DIVIDE */
      {
!       dPOPPOPnnrl;
!       if (right == 0.0)
!           DIE(aTHX_ "Illegal division by zero");
        PUSHn( left / right );
        RETURN;
      }
--- 1276,1288 ----
      } /* right wasn't SvIOK */
  #endif /* PERL_TRY_UV_DIVIDE */
      {
!         dPOPPOPnnrl;
! #if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
!       if (! Perl_isnan(right) && right == 0.0)
! #else
!       if (right == 0.0)
! #endif
!             DIE(aTHX_ "Illegal division by zero");
        PUSHn( left / right );
        RETURN;
      }

Let me know if you need further information

Patrick DUGNOLLE

perlbug -d
---
Flags:
    category=
    severity=
---
Site configuration information for perl 5.9.4:

Configured by 225028 at Thu Apr 19 10:57:25 2007.

Summary of my perl5 (revision 5 version 9 subversion 4) configuration:
  Platform:
    osname=MSWin32, osvers=5.1, archname=MSWin32-x86-multi-thread
    uname=''
    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='cl', ccflags ='-nologo -GF -W3 -MD -Zi -DNDEBUG -O1 -DWIN32 
-D_CONSOLE -DNO_STRICT -DHAVE_DES_FCRYPT  -DPERL_IMPLICIT_CONTEXT 
-DPERL_IMPLICIT_SYS -DUSE_PERLIO -DPERL_MSVCRT_READFIX',
    optimize='-MD -Zi -DNDEBUG -O1',
    cppflags='-DWIN32'
    ccversion='12.00.8804', gccversion='', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
    d_longlong=undef, longlongsize=8, d_longdbl=define, longdblsize=10
    ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='__int64', 
lseeksize=8
    alignbytes=8, prototype=define
  Linker and Libraries:
    ld='link', ldflags ='-nologo -nodefaultlib -debug -opt:ref,icf 
-libpath:"c:\Appli\GTS\Dev\Perl\lib\CORE"  -machine:x86'
    libpth=C:\PROGRA~1\MICROS~3\VC98\lib
    libs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib 
comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib  netapi32.lib 
uuid.lib ws2_32.lib mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib 
msvcrt.lib
    perllibs=  oldnames.lib kernel32.lib user32.lib gdi32.lib winspool.lib 
 comdlg32.lib advapi32.lib shell32.lib ole32.lib oleaut32.lib netapi32.lib 
uuid.lib ws2_32.lib mpr.lib winmm.lib  version.lib odbc32.lib odbccp32.lib 
msvcrt.lib
    libc=msvcrt.lib, so=dll, useshrplib=yes, libperl=perl59.lib
    gnulibc_version=''
  Dynamic Linking:
    dlsrc=dl_win32.xs, dlext=dll, d_dlsymun=undef, ccdlflags=' '
    cccdlflags=' ', lddlflags='-dll -nologo -nodefaultlib -debug 
-opt:ref,icf  -libpath:"c:\Appli\GTS\Dev\Perl\lib\CORE"  -machine:x86'

Locally applied patches:
 

---
@INC for perl 5.9.4:
    C:/Appli/GTS/Dev/Perl/lib
    C:/Appli/GTS/Dev/Perl/site/lib
    .

---
Environment for perl 5.9.4:
    HOME (unset)
    LANG (unset)
    LANGUAGE (unset)
    LD_LIBRARY_PATH (unset)
    LOGDIR (unset)
 
PATH=C:\Appli\GTS\Dev\Perl\bin;C:\PROGRA~1\MICROS~3\Common\msdev98\BIN;C:\PROGRA~1\MICROS~3\VC98\BIN;C:\PROGRA~1\MICROS~3\Common\TOOLS\WINNT;C:\PROGRA~1\MICROS~3\Common\TOOLS;C:\Perl\site\bin;C:\Perl\bin;C:\Perl\bin\;C:\WINDOWS\System32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\infAppdata\Notes\data;C:\Program 
Files\IDEpro\Ultraedit92\;C:\Program Files\Microsoft SQL 
Server\80\Tools\BINN;C:\Program 
Files\OpenSource\PuTTY;X:\Appli\Gts\Gnu32\Bin
    PERL_BADLANG (unset)
    SHELL (unset)


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• [perl #42614] NAN_COMPARE_BROKEN.DIV_BY_NAN_BUG (with patch) by patrick . dugnolle @ bnpparibas . com
• Re: [perl #42614] NAN_COMPARE_BROKEN.DIV_BY_NAN_BUG (with patch) by Rafael Garcia-Suarez