Re: build error

From: Matteo Croce <mcroce@redhat.com>
To: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: build error
Date: Mon, 29 Jul 2019 13:12:45 +0200	[thread overview]
Message-ID: <CAGnkfhx6St+MYQuR_Duguk4Q9ieuL7sLCTL=G76-eqUcCAbpoA@mail.gmail.com> (raw)
In-Reply-To: <cc6f9c8f-a4a1-7c71-1f89-72e1e8dd0cc8@arm.com>

On Mon, Jul 29, 2019 at 1:08 PM Vincenzo Frascino
<vincenzo.frascino@arm.com> wrote:
>
> Hi Matteo,
>
> On 29/07/2019 11:25, Matteo Croce wrote:
> > On Mon, Jul 29, 2019 at 12:16 PM Vincenzo Frascino
> > <vincenzo.frascino@arm.com> wrote:
> >>
> >> Hi Matteo and Will,
> >>
> >>
> >> If I try to build a fresh kernel on my machine with the standard "make mrproper
> >> && make defconfig && make" I do not see the reported issue (Please see below
> >> scissors).
> >>
> >> At this point would be interesting to know more about how Matteo is building the
> >> kernel, and try to reproduce the issue here.
> >>
> >> @Matteo, could you please provide the full .config and the steps you used to
> >> generate it? Is it an 'oldconfig'?
> >>
> >
> > Hi,
> >
> > yes, this is an oldconfig from a vanilla 5.2, I attach it
> > (the non gzipped config was dropped by the ML filter)
> >
> >
>
> I tried your config file and seems working correctly:
>
> # cp ~/config ../linux-out/.config
> # make oldconfig
> # make
>
> arch/arm64/Makefile:56: CROSS_COMPILE_COMPAT not defined or empty, the compat
> vDSO will not be built
>
> ---
>
> Could you please send to me the config file that does not contain:
> CONFIG_CROSS_COMPILE_COMPAT_VDSO=""
>
> The original one I mean, on which you did not run make oldconfig.
> My suspect at this point is that the string passed to
> CONFIG_CROSS_COMPILE_COMPAT_VDSO is not completely empty.
>
> In fact if I do CONFIG_CROSS_COMPILE_COMPAT_VDSO=" " (single space),
> I do have a failure similar to the one you reported.
>

That's what I initially thought, but the string is effectively empty:

# make
arch/arm64/Makefile:58: *** gcc not found, check CROSS_COMPILE_COMPAT.  Stop.
# grep CROSS_COMPILE_COMPAT_VDSO .config |hexdump -C
00000000  43 4f 4e 46 49 47 5f 43  52 4f 53 53 5f 43 4f 4d  |CONFIG_CROSS_COM|
00000010  50 49 4c 45 5f 43 4f 4d  50 41 54 5f 56 44 53 4f  |PILE_COMPAT_VDSO|
00000020  3d 22 22 0a                                       |="".|
00000024

-- 
Matteo Croce
per aspera ad upstream