Summary of my perl5 (revision 5 version 18 subversion 4) configuration: Platform: osname=linux, osvers=3.14-2-amd64, archname=x86_64-linux uname='linux reini 3.14-2-amd64 #1 smp debian 3.14.15-2 (2014-08-09) x86_64 gnulinux ' config_args='-de -Dusedevel -Uversiononly -Dinstallman1dir=none -Dinstallman3dir=none -Dinstallsiteman1dir=none -Dinstallsiteman3dir=none -Uuseithreads -Accflags=''-msse4.2'' -Accflags=''-march=corei7'' -Dcf_email=''rurban@cpanel.net'' -Dperladmin=''rurban@cpanel.net''' hint=recommended, useposix=true, d_sigaction=define useithreads=undef, usemultiplicity=undef useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef use64bitint=define, use64bitall=define, uselongdouble=undef usemymalloc=n, bincompat5005=undef Compiler: cc='gcc-4.9', ccflags ='-msse4.2 -march=corei7 -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64', optimize='-O2', cppflags='-msse4.2 -march=corei7 -fno-strict-aliasing -pipe -fstack-protector -I/usr/local/include' ccversion='', gccversion='4.9.1', 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 Linker and Libraries: ld='cc', ldflags =' -fstack-protector -L/usr/local/lib' libpth=/usr/local/lib /lib/x86_64-linux-gnu /lib/../lib /usr/lib/x86_64-linux-gnu /usr/lib/../lib /lib /usr/lib /lib64 /usr/lib64 libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc -lgdbm_compat perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc libc=libc-2.19.so, so=so, useshrplib=false, libperl=libperl.a gnulibc_version='2.19' Dynamic Linking: dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E' cccdlflags='-fPIC', lddlflags='-shared -O2 -L/usr/local/lib -fstack-protector' Characteristics of this binary (from libperl): Compile-time options: HAS_TIMES PERLIO_LAYERS PERL_DONT_CREATE_GVSV PERL_HASH_FUNC_ONE_AT_A_TIME_HARD PERL_MALLOC_WRAP PERL_PRESERVE_IVUV PERL_SAWAMPERSAND PERL_USE_DEVEL USE_64_BIT_ALL USE_64_BIT_INT USE_LARGE_FILES USE_LOCALE USE_LOCALE_COLLATE USE_LOCALE_CTYPE USE_LOCALE_NUMERIC USE_PERLIO USE_PERL_ATOF Built under linux Compiled at Dec 11 2014 07:40:09 @INC: /usr/local/lib/perl5/site_perl/5.18.4/x86_64-linux /usr/local/lib/perl5/site_perl/5.18.4 /usr/local/lib/perl5/5.18.4/x86_64-linux /usr/local/lib/perl5/5.18.4 /usr/local/lib/perl5/site_perl/5.16.3 /usr/local/lib/perl5/site_perl/5.14.4 /usr/local/lib/perl5/site_perl/5.14.3 /usr/local/lib/perl5/site_perl/5.12.5 /usr/local/lib/perl5/site_perl/5.10.1 /usr/local/lib/perl5/site_perl/5.8.9 /usr/local/lib/perl5/site_perl/5.8.8 /usr/local/lib/perl5/site_perl/5.8.5 /usr/local/lib/perl5/site_perl/5.8.4 /usr/local/lib/perl5/site_perl/5.6.2 /usr/local/lib/perl5/site_perl .