hello, Regarding my problem, I searched the list archives and did found some mpu emul related posts but they were not exactly like my case.
Basically, I have an RPX Lite-M board. The mpc850 does not have an fpu, but I have a need for non-intensive fpu operations. I don't want to compile applications and librairies with -msoft-float - for my needs the fpu emulator is really the way to go. The board successfully boots a slightly modified linux 2.4.9. I've compiled the kernel with and without math emulation. I also compiled a very simple application that does a floating point division and prints it. I explicitly specified -msoft-hard. (same with the kernel btw), checked out the resulting assembly and did in fact find an fdiv instruction. Without the emulation, executing the program results in a floating point exception. This is normal. With the math emu kernel, the exception is caught and seemingly handled as it should. However, a printf of a float results in "nan" (not a number). If I invoke the printf binary (printf "%f\n" 43.34343) it is able to print a float. I didn't compile my own toolchain. I switch between the binary distributions I got from www.qslinux.org and timesys. I'm not sure this is a good idea. Any ideas as to what could be wrong? Could it be that the libs in the root filesystem I'm using for the board were compiled with -msoft-float, and that as a result printf cannot properly output a float? (even though it's been properly handled by the fpu emulator?) Thank you, Alban ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
