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Re: [PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON files with clang

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On Thursday 18 February 2016 12:31:35 Nicolas Pitre wrote:
> On Thu, 18 Feb 2016, Arnd Bergmann wrote:
> 
> > clang ignores the -mfpu=neon flag when building with -march=armv6:
> > 
> > In file included from lib/raid6/neon1.c:27:
> > clang/3.8.0/include/arm_neon.h:28:2: error: "NEON support not enabled"
> > 
> > There is no real need to build the file with -march=armv6 in a
> > multi-CPU enabled kernel, as nothing in here will ever get called
> > on an ARMv6 CPU. Adding -march=armv7 doesn't hurt and can only
> > improve the code quality.
> 
> Is this enough to override a previous -mfpu for gcc?

I did not see any build failures on gcc with this, so I assume it
has no effect. I could move the -march=armv7-a in front of
-mfpu=neon if you think that would be safer though.

	Arnd

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[PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON files with clang Arnd Bergmann <arnd@arndb.de> - 2016-02-18 18:10 +0100
  Re: [PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON  files with clang Nicolas Pitre <nicolas.pitre@linaro.org> - 2016-02-18 18:40 +0100
    Re: [PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON files with clang Arnd Bergmann <arnd@arndb.de> - 2016-02-19 15:30 +0100
      Re: [PATCH 1/3] [RESEND] ARM: pass -march=armv7-a when building NEON  files with clang Nicolas Pitre <nicolas.pitre@linaro.org> - 2016-02-19 18:10 +0100

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