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Re: newlib on powerpc-eabi with soft-float



>However, the target processor (MC8260) has no floating point unit and
>I'm not sure whether Newlib is aware of this. Specifically, in
>setjmp.S, there are a few lines of code to save the floating point
>registers (which the MC8260 does not have) wrapped in an #ifndef
>_SOFT_FLOAT.  I'm guessing that _SOFT_FLOAT should be being defined
>somewhere, but I'm not sure where. Is there any option that I can give
>to the configuration script such that this macro will be defined? I'm
>not too keen on hacking the code since I'm sue that there must be
>another way... 

If I remember gcc-3.95.3 correctly, the ppc compiler you're build is for
all of the ppc variants out there, both with and without floating point.

If you add '-msoft-float' to both your compilation lines and link
line(using gcc to driver the linker), the compiler won't generate any
FPU instructions, and the library you link with won't use any FPU
instructions.  You could generate a map file (add -Wl,-Map,mapfile to
the gcc line used to link the program) and see which object files from
which libraries were linked.

You should use gcc to driver the linker since it knows how to decipher
-msoft-float and pick the appropriate libraries to pass to the linker.

Good Luck!

-- 
Peter Barada                                   Peter.Barada@motorola.com
Wizard                                         781-852-2768 (direct)
WaveMark Solutions(wholly owned by Motorola)   781-270-0193 (fax)

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