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On 31 Jan 2004 at 17:34, David Wuertele wrote: > >> And now my build will finally progress past this point. > >> Doesn't anyone else have this problem? Where the heck do I get the > >> lib/nof/* files? Generally you will get them by compiling glibc once again with the '-msoft-float' option. > Dan> You don't need those files unless you have a CPU that doesn't > Dan> support floating point (and even then, they might be somewhere > Dan> else; that path is right for how the ppc405 is set up). The Linux kernel should take care of the FPU-emulation, but as its comments ('arch/mips/math-emu') are telling: ------------------------------- clip ---------------------------- /home2/src/linux-2.4.22/arch/mips/math-emu > less cp1emu.c /* * cp1emu.c: a MIPS coprocessor 1 (fpu) instruction emulator * * MIPS floating point support * Copyright (C) 1994-2000 Algorithmics Ltd. All rights reserved. * http://www.algor.co.uk * * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com * Copyright (C) 2000 MIPS Technologies, Inc. * <snip> * A complete emulator for MIPS coprocessor 1 instructions. This is * required for #float(switch) or #float(trap), where it catches all * COP1 instructions via the "CoProcessor Unusable" exception. * * More surprisingly it is also required for #float(ieee), to help out * the hardware fpu at the boundaries of the IEEE-754 representation * (denormalised values, infinities, underflow, etc). It is made * quite nasty because emulation of some non-COP1 instructions is * required, e.g. in branch delay slots. * * Note if you know that you won't have an fpu, then you'll get much * better performance by compiling with -msoft-float! */ ------------------------------- clip ---------------------------- the '-msoft-float' option which produces direct calls to the basic soft-float routines, can cause a better performance... > My CPU has no floating point unit. I looked around for nof/*, but > didn't find anything. Any suggestions? The point is that providing the '-msoft-float' specific glibc should not be obligatory... You can build it and try it and see whether it helps to better the float performance. Visiting the 'http://www.algor.co.uk' and seeing what they are telling about MIPS, could be useful... My stupid question related to this area is: "What is the difference between the 'mips(el)-linux-gnu' and the 'mipsisa32(el)-linux-gnu' targets?" The latter seems to default to the '-msoft-float', but what is the main difference and why the people who don't have a FPU, don't use this target name? Cheers, Kai ------ Want more information? See the CrossGCC FAQ, http://www.objsw.com/CrossGCC/ Want to unsubscribe? Send a note to crossgcc-unsubscribe@sources.redhat.com
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