$ /usr/local/perl/5.14.2/bin/perl -we '$v=""; vec($v,4060380287,1)=1'
Negative offset to vec in lvalue context at -e line 1.
$ /usr/local/perl/5.15.8/bin/perl -we '$v=""; vec($v,4060380287,1)=1'
Negative offset to vec in lvalue context at -e line 1.

##</code><code>##

...
  Compiler:
    cc='gcc ', ccflags ='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64',
    optimize='-O2',
    cppflags='-D_REENTRANT -D_GNU_SOURCE -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include'
    ccversion='', gccversion='4.3.2 [gcc-4_3-branch revision 141291]', gccosandvers=''
    intsize=4, longsize=8, ptrsize=8, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=16
    ivtype='long', ivsize=8, nvtype='double', nvsize=8, Off_t='off_t', lseeksize=8
    alignbytes=8, prototype=define
...
Characteristics of this binary (from libperl): 
  Compile-time options: HAS_TIMES MULTIPLICITY PERLIO_LAYERS
                        PERL_DONT_CREATE_GVSV PERL_IMPLICIT_CONTEXT
                        PERL_MALLOC_WRAP PERL_PRESERVE_IVUV PERL_USE_DEVEL
                        USE_64_BIT_ALL USE_64_BIT_INT USE_ITHREADS
                        USE_LARGE_FILES USE_LOCALE USE_LOCALE_COLLATE
                        USE_LOCALE_CTYPE USE_LOCALE_NUMERIC USE_PERLIO
                        USE_PERL_ATOF USE_REENTRANT_API

##</code><code>##

$ perl -wE '$v=""; vec($v,2**32+42,1)=1; say "wrapped" if vec($v,42,1)'
wrapped