A much longer than expected discussion, but informative none the less. Thanks to all for explaining.
And here one can see the difference. Static vs Dynamic executable. $ ldd bench1.cthreads linux-vdso.so.1 => (0x00007fff3f5ff000) libdl.so.2 => /lib/libdl.so.2 (0x00007f4b371b5000) libc.so.6 => /lib/libc.so.6 (0x00007f4b36e43000) /lib64/ld-linux-x86-64.so.2 (0x00007f4b373b9000) $ ldd bench1.no-cthreads not a dynamic executable $ ls -l -rwxr-xr-x 1 graemeg graemeg 693840 2009-08-27 14:11 bench1.cthreads -rwxr-xr-x 1 graemeg graemeg 607112 2009-08-27 14:11 bench1.no-cthreads Regards, - Graeme - -- fpGUI Toolkit - a cross-platform GUI toolkit using Free Pascal http://opensoft.homeip.net/fpgui/ _______________________________________________ fpc-pascal maillist - fpc-pascal@lists.freepascal.org http://lists.freepascal.org/mailman/listinfo/fpc-pascal