On Sun, Jun 15, 2003 at 12:01:00AM -0400, Brian C Miles wrote: > > While building 2.4.21 on my SS20 SMP box, I noticed "-mno-fpu" being used > as a CFLAG. Does anyone know why? This isn't an indication that fp > emulation is being compiled into the kernel (i.e. though it may very well > be), but a directive to tell GCC to try and use software implementations > of fp math. Does anyone know why this is enabled by default? Does this > have any negative performance impact on machines that have hardware FPU? > Is it safe to compile the kernel without this flag? > > There are several dead-end threads about this topic on various newsgroup > archives. If any one could shed some light on this, it would be much > appreciated.
There is no floating point used in the kernel. So it has no real affect. I don't know for sure, but -mno-fpu may also allow the compiler to make some assumptions about the code it is compiling, for better scheduling and performance. -- Debian - http://www.debian.org/ Linux 1394 - http://www.linux1394.org/ Subversion - http://subversion.tigris.org/ Deqo - http://www.deqo.com/
