Hello, > -----Original Message----- > From: Rob Herring [mailto:robh at kernel.org] > Sent: Friday, September 14, 2018 12:04 AM > To: Alexey.Brodkin at synopsys.com > Cc: linux-snps-arc at lists.infradead.org; Linux Kernel Mailing List <linux-kernel at vger.kernel.org>; Vineet.Gupta1 at synopsys.com > Subject: Re: [PATCH] ARC: Get rid of toolchain check > > On Thu, Sep 13, 2018 at 3:24 PM Alexey Brodkin > <Alexey.Brodkin at synopsys.com> wrote: > > > > This check is very naive: we simply test if GCC invoked without > > "-mcpu=XXX" has ARC700 define set. In that case we think that GCC > > was built with "--with-cpu=arc700" and has libgcc built for ARC700. > > > > Otherwise if ARC700 is not defined we think that everythng was built > > for ARCv2. > > > > But in reality our life is much more interesting. > > > > 1. Regardless of GCC configuration (i.e. what we pass in "--with-cpu" > > it may generate code for any ARC core). > > > > 2. libgcc might be built with explicitly specified "--mcpu=YYY" > > > > That's exactly what happens in case of multilibbed toolchains: > > - GCC is configured with default settings > > - All the libs built for many different CPU flavors > > > > I.e. that check gets in the way of usage of multilibbed > > toolchains. And even non-multilibbed toolchains are affected. > > OpenEmbedded also builds GCC without "--with-cpu" because > > each and every target component later is compiled with explicitly > > set "-mcpu=ZZZ". > > > > Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com> > > --- > > arch/arc/Makefile | 14 -------------- > > 1 file changed, 14 deletions(-) > > +1 for this. Removing it also helps with my work to be able to build > all the .dts files with only a host compiler. That also needs the hunk > setting CROSS_COMPILE removed and not having a built-in dtb by > default, but this is a step in the right direction. > > Acked-by: Rob Herring <robh at kernel.org> May we get this one back-ported to stable trees? Upstream commit in Linus' tree is 615f64458ad8 ("ARC: build: Get rid of toolchain check"). This fixes kernel configuration for ARC in case of missing ARC cross-tools in current PATH. -Alexey
