aix                  for AIX 4.x xlC
aix5                 for AIX 5.x xlC
aixgcc               for AIX 5.x gcc >= 3
alphacxx6            for DEC Unix cxx6
alphagcc             for DEC Unix gcc
alphakcc             for DEC Unix KCC
freebsd              for FreeBSD
freebsd4             for FreeBSD 4.x
freebsd5             for FreeBSD 5.x and 6.x
hpuxacc              for HP-UX 10.20 aCC
hpuxgcc              for HP-UX 10.20 gcc
hpuxia64acc          for HP-UX 11i v1.5 (IA-64) aCC
hurddeb              for Debian GNU/Hurd with gcc and glibc
linux                for Linux gcc 2.9x, gcc 3.x and glibc
linuxalphagcc        for Alpha Linux gcc and glibc
linuxarm             for ARM Linux gcc and glibc
linuxdeb             for Debian GNU/Linux v2.1+ gcc and glibc
linuxdeb2ppc         for PPC Linux based on Debian v2.0
linuxia64ecc         for Itanium Linux Intel ecc and glibc
linuxia64gcc         for Itanium Linux gcc 2.9x and glibc
linuxia64sgi         for Itanium Linux sgiCC and glibc
linuxicc             for Linux Intel's icc and glibc
linuxkcc             for Linux KAI's KCC and glibc
linuxpgcc            for Linux pgcc and glibc
linuxppcgcc          for PPC Linux gcc and glibc
linuxppc64gcc        for PPC 64 Linux gcc 3.x and glibc
linuxrh42            for Linux gcc 2.7.x.x and libc5
linuxrh51            for Linux gcc 2.7.x.x and glibc
linuxsuse6           for Linux (SuSE v6.0) gcc and glibc
linuxx8664gcc        for AMD Opteron and Intel EM64T Linux gcc 3.x and glibc
linuxx8664icc        for AMD Opteron and Intel EM64T Linux gcc 3.x and glibc
lynxos               for LynxOS with gcc
macosx               for MacOS X with gcc
macosxicc            for MacOS X with Intel icc compilers (MacTel only)
macosx64             for MacOS X with gcc 4.0 64 bit mode
macosxxlc            for MacOS X with IBM xl compilers
mklinux              for MkLinux gcc and glibc
openbsd              for OpenBSD >= 3.7
sgicc                for SGI IRIX 6.x CC
sgicc64              for SGI IRIX 6.x CC 64 bits
sgigcc               for SGI IRIX 6.x gcc
sgikcc               for SGI IRIX 6.x KCC
sgin32gcc            for SGI IRIX 6.4 gcc using n32 ABI
solaris              for Solaris CC
solarisCC5           for Solaris CC 5.0
solarisgcc           for Solaris gcc
solariskcc           for Solaris KCC
win32                for Win32 with VC++ and gdk based GUI
win32gcc             for Win32 with cygwin/gcc