Re: [arm-gnu] unimplemented: -mfloat-abi=hard and VFP?

[Paul Brook <paul@xxxxxxxxxxxxxxxx>]

On Saturday 06 August 2005 09:59, Ioi Lam wrote:
> Hi,
>
> Is VFP support not implemented in GCC yet? I am using the 2005Q1B
> release (downloaded from ARM's web site)
>
> /gcc/2005Q1B/bin/arm-none-linux-gnueabi-gcc -march=armv5te -mfpu=vfp
> -mhard-float -O -o - -S vfp.c
> vfp.c:1: sorry, unimplemented: -mfloat-abi=hard and VFP
>         .file   "vfp.c"
>         .comm   k,4,4
>         .ident  "GCC: (GNU) 3.4.3 (release) (CodeSourcery ARM Q1B 2005)"
>
> FPA seems to work fine, but it doesn't generate the VFP instructions (as
> generated by ADS)
>
> /gcc/2005Q1B/bin/arm-none-linux-gnueabi-gcc -march=armv5te -mfpu=fpa
> -mhard-float -O -o - -S vfp.c

You need to use -mfpu=vfp -mfloat-abi=softfp.

This will generating hardware floating point instructions while still 
conforming to the base (soft-float) AAPCS. GCC does not support the 
hard-float abi variant for vfp.

This is mentioned in our toolchain FAQ.
http://www.codesourcery.com/gnu_toolchains/arm/faq.html#q_2_2

Paul