[perl #105920] Perl parser sometimes tolerates stray nulls, sometimes not

On Sun Dec 11 13:15:49 2011, sprout wrote:
> Stray nulls are tolerated in files but not in string evals.  Why is
> that?  I know which piece of code is doing it, but is it by design?
> Why the inconsistency?
> 
> #!perl -l
> print eval "6+5\0+3";
> warn $@ if $@;
> 
> require PerlIO::scalar;
> unshift @INC, sub {
>     return unless $_[1] eq 'foo.pm';
>     open my $fh, '<', \"6+5\0+3"; $fh
> };
> print require foo;
> __END__
> 
> This prints:
> 
> syntax error at (eval 1) line 1, at EOF
> 14
> 
> ---
> Flags:
>     category=core
>     severity=low
> ---
> Site configuration information for perl 5.15.5:
> 
> Configured by sprout at Sat Nov 26 11:40:22 PST 2011.
> 
> Summary of my perl5 (revision 5 version 15 subversion 5)
> configuration:
>   Snapshot of: c071f8d7e26d951a082adc9cd79aae32680c01ae
>   Platform:
>     osname=darwin, osvers=10.5.0, archname=darwin-thread-multi-2level
>     uname='darwin pint.local 10.5.0 darwin kernel version 10.5.0: fri
> nov 5 23:20:39 pdt 2010; root:xnu-1504.9.17~1release_i386 i386 '
>     config_args='-de -Dusedevel -Duseithreads -Dmad'
>     hint=recommended, useposix=true, d_sigaction=define
>     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 ='-fno-common -DPERL_DARWIN -fno-strict-aliasing
> -pipe -fstack-protector -I/usr/local/include',
>     optimize='-O3',
>     cppflags='-fno-common -DPERL_DARWIN -fno-strict-aliasing -pipe
> -fstack-protector -I/usr/local/include'
>     ccversion='', gccversion='4.2.1 (Apple Inc. build 5664)',
> gccosandvers=''
>     intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=1234
>     d_longlong=define, longlongsize=8, d_longdbl=define,
> longdblsize=16
>     ivtype='long', ivsize=4, nvtype='double', nvsize=8, Off_t='off_t',
> lseeksize=8
>     alignbytes=8, prototype=define
>   Linker and Libraries:
>     ld='env MACOSX_DEPLOYMENT_TARGET=10.3 cc', ldflags ='
> -fstack-protector -L/usr/local/lib'
>     libpth=/usr/local/lib /usr/lib
>     libs=-ldbm -ldl -lm -lutil -lc
>     perllibs=-ldl -lm -lutil -lc
>     libc=, so=dylib, useshrplib=false, libperl=libperl.a
>     gnulibc_version=''
>   Dynamic Linking:
>     dlsrc=dl_dlopen.xs, dlext=bundle, d_dlsymun=undef, ccdlflags=' '
>     cccdlflags=' ', lddlflags=' -bundle -undefined dynamic_lookup
> -L/usr/local/lib -fstack-protector'
> 
> Locally applied patches:
> 
> 
> ---
> @INC for perl 5.15.5:
>     /usr/local/lib/perl5/site_perl/5.15.5/darwin-thread-multi-2level
>     /usr/local/lib/perl5/site_perl/5.15.5
>     /usr/local/lib/perl5/5.15.5/darwin-thread-multi-2level
>     /usr/local/lib/perl5/5.15.5
>     /usr/local/lib/perl5/site_perl
>     .
> 
> ---
> Environment for perl 5.15.5:
>     DYLD_LIBRARY_PATH (unset)
>     HOME=/Users/sprout
>     LANG=en_US.UTF-8
>     LANGUAGE (unset)
>     LD_LIBRARY_PATH (unset)
>     LOGDIR (unset)
>    
PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin:/usr/local/bin
>     PERL_BADLANG (unset)
>     SHELL=/bin/bash
> 

I would imagine this was not by design -- probably a leftover from back
when Perl used strlen() extensively.

--hugmeir


---
via perlbug:  queue: perl5 status: new
https://rt.perl.org:443/rt3/Ticket/Display.html?id=105920

• [perl #105920] Perl parser sometimes tolerates stray nulls, sometimes not by Brian Fraser via RT