Re: [PATCH 4.19 66/81] MIPS: Disable Loongson MMI instructions for kernel build

[Greg Kroah-Hartman]

On Wed, Aug 26, 2020 at 02:06:28PM -0700, Guenter Roeck wrote:
> Hi,
> 
> On Wed, Oct 16, 2019 at 02:51:17PM -0700, Greg Kroah-Hartman wrote:
> > From: Paul Burton <paul.burton@xxxxxxxx>
> > 
> > commit 2f2b4fd674cadd8c6b40eb629e140a14db4068fd upstream.
> > 
> > GCC 9.x automatically enables support for Loongson MMI instructions when
> > using some -march= flags, and then errors out when -msoft-float is
> > specified with:
> > 
> >   cc1: error: ‘-mloongson-mmi’ must be used with ‘-mhard-float’
> > 
> > The kernel shouldn't be using these MMI instructions anyway, just as it
> > doesn't use floating point instructions. Explicitly disable them in
> > order to fix the build with GCC 9.x.
> > 
> 
> I still see this problem when trying to compile fuloong2e_defconfig with
> gcc 9.x or later. Reason seems to be that the patch was applied to
> arch/mips/loongson64/Platform, but fuloong2e_defconfig uses
> arch/mips/loongson2ef/Platform.
> 
> Am I missing something ?

I don't know, sorry, that would be something that Paul understands.

Paul?