I've built a toolchain w/the multilib as in the attached t-arm-elf. http://www.zylin.com/gccbinary.html However, multilib and Cortex has some hickups w.r.t. floating point format, which requires floating point format to be specified on the command line. /* Test app to check that multilib works */ int main(int argc, char **argv) { } Invoke: arm-elf-gcc -mfpu=vfp -mcpu=cortex-m3 -mthumb test.c And you get: /tmp/cccL5n1B.o uses FPA instructions, whereas a.out does not The solution is to add -mfpu=vfp to the command line: arm-elf-gcc -mfpu=vfp -mcpu=cortex-m3 -mthumb test.c Here is what I believe is going on: There are two different types of floating point VFP and FPA. The key point is that they are not compatible. Does -march=armv7 imply VFP, whereas mcpu=cortex-m3 does not? Binutils produces an error message that is misleading. The real problem is that the types of floating point are being mixed. Is this behaviour intentional? Should I add VFP & FPA to t-arm-elf as multilib permutations? -- Øyvind Harboe http://www.zylin.com/zy1000.html ARM7 ARM9 XScale Cortex JTAG debugger and flash programmer Free eCos workshop in Oslo October 21! http://www.zylin.com/workshop.html
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