Arm toolchain with gcc / newlib / VFP / hard float - can it be done?

[Joe Button]

On 26/02/13 10:24, Freddie Chopin wrote:
> W dniu 2013-02-26 10:57, Joe Button pisze:
>>> That's why I suggested taking a look at the linaro toolchain, as in it
>>> newlib is built so that newlib takes multilib into account. What does
>>> your gcc say when you do:
>>> <prefix>-gcc -print-multi-lib
>> ./arm-none-eabi-gcc -print-multi-lib
>> .;
>> thumb;@mthumb
>> fpu;@mfloat-abi=hard
>
> So this look a bit short... In here I got sth like:
>
>> >arm-none-eabi-gcc -print-multi-lib
>> .;
>> thumb;@mthumb
>> fpu;@mfloat-abi=hard
>> armv6-m;@mthumb@march=armv6s-m
>> armv7-m;@mthumb@march=armv7-m
>> armv7e-m;@mthumb@march=armv7e-m
>> armv7-r/thumb;@mthumb@march=armv7-r
>> armv7e-m/softfp;@mthumb@march=armv7e-m@mfloat-abi=softfp@mfpu=fpv4-sp-d16 
>>
>> armv7e-m/fpu;@mthumb@march=armv7e-m@mfloat-abi=hard@mfpu=fpv4-sp-d16
>> armv7-r/thumb/softfp;@mthumb@march=armv7-r@mfloat-abi=softfp@mfpu=vfpv3-d16 
>>
>> armv7-r/thumb/fpu;@mthumb@march=armv7-r@mfloat-abi=hard@mfpu=vfpv3-d16
>
> The lines you have are for "default arch", which - as I said - (from 
> what I know) is ARMv4 (ARM7TDMI etc.), for your chip I guess you 
> should have sth like (just a guess):
> "armv5/fpu;@march=armv5@mfloat-abi=hard"
>
> And your GCC can generate code for ARMv5 (it would probably happily 
> generate code for Cortex-A15 too (; ), it just doesn't have libraries 
> for it, so you cannot use anything that comes from library (like 
> sqrt(), printf(), malloc(), ...).
>
> 4\/3!!

Hi. I feel like I should report back that I eventually got rid of the 
vfp abi errors, not by patching gcc or anything complicated but by 
setting my LIB path correctly. Vive l'incompetence.

Thanks,

Joe