Subject: Re: [v5 1/2] lib/raid6: Build proper files on corresponding arch

From: Michael Ellerman <[email-masked]>
Date: Wed, 02 Aug 2017 12:00:53 +1000

Daniel Axtens <[email-masked]> writes:

> Hi Matt,
>
>> --- a/lib/raid6/test/Makefile
>> +++ b/lib/raid6/test/Makefile
>> @@ -44,10 +44,12 @@ else ifeq ($(HAS_NEON),yes)
>>          CFLAGS += -DCONFIG_KERNEL_MODE_NEON=1
>>  else
>>          HAS_ALTIVEC := $(shell printf '\#include <altivec.h>\nvector int a;\n' |\
>> -                         gcc -c -x c - >&/dev/null && \
>> -                         rm ./-.o && echo yes)
>> +                         gcc -c -x c - >/dev/null && rm ./-.o && echo yes)
>
> From memory the change here (s/>&/>/) was necessary to get the build to
> succeed - did we ever figure out why that was? I'm not enough of a shell
> guru to grok the difference.

Using >& redirects stdout and stderr, whereas > only redirects stdout.

So possibly it doesn't fix anything, but rather lets you see any error
emitted by the compiler rather than swallowing it?

cheers