From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnout Vandecappelle Date: Tue, 3 Nov 2015 22:45:15 +0100 Subject: [Buildroot] [PATCH] arch/arm: VFP and Thumb1 are not compatible In-Reply-To: <1446507277-26679-1-git-send-email-yann.morin.1998@free.fr> References: <1446507277-26679-1-git-send-email-yann.morin.1998@free.fr> Message-ID: <56392AEB.40503@mind.be> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 03-11-15 00:34, Yann E. MORIN wrote: > gcc will refuse to build with both --with-mode=thumb and --with-fpu=vfp, > with error messages during ./configure, like: > > checking for suffix of object files... configure: error: in `/home/ymor > in/dev/buildroot/O/build/host-gcc-initial-4.9.3/build/arm-buildroot-lin > ux-uclibcgnueabihf/libgcc': > configure: error: cannot compute suffix of object files: cannot compile > See `config.log' for more details. > > And config.log informatively contains: > > sorry, unimplemented: Thumb-1 hard-float VFP ABI > > This is an error message that comes deep from gcc source files. > > If gcc says it does not support VFP with Thumb1, then let's disable that > combination in our menuconfig. > > Prefer VFP over Thumb1, i.e. hide Thumb1 when we're not soft-float. > > Signed-off-by: "Yann E. MORIN" > Cc: Gustavo Zacarias > Cc: Thomas Petazzoni Acked-by: Arnout Vandecappelle (Essensium/Mind) Regards, Arnout > --- > arch/Config.in.arm | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/Config.in.arm b/arch/Config.in.arm > index db7b8f2..67ff384 100644 > --- a/arch/Config.in.arm > +++ b/arch/Config.in.arm > @@ -377,12 +377,18 @@ config BR2_ARM_INSTRUCTIONS_ARM > config BR2_ARM_INSTRUCTIONS_THUMB > bool "Thumb" > depends on BR2_ARM_CPU_HAS_THUMB > + # Thumb-1 and VFP are not compatible > + depends on BR2_ARM_SOFT_FLOAT > help > This option instructions the compiler to generate Thumb > instructions, which allows to mix 16 bits instructions and > 32 bits instructions. This generally provides a much smaller > compiled binary size. > > +comment "Thumb1 is not compatible with VFP" > + depends on BR2_ARM_CPU_HAS_THUMB > + depends on !BR2_ARM_SOFT_FLOAT > + > config BR2_ARM_INSTRUCTIONS_THUMB2 > bool "Thumb2" > depends on BR2_ARM_CPU_HAS_THUMB2 > -- Arnout Vandecappelle arnout at mind be Senior Embedded Software Architect +32-16-286500 Essensium/Mind http://www.mind.be G.Geenslaan 9, 3001 Leuven, Belgium BE 872 984 063 RPR Leuven LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle GPG fingerprint: 7493 020B C7E3 8618 8DEC 222C 82EB F404 F9AC 0DDF