Re: [PATCH] powerpc: Automatically guess --with-cpu value

["Tulio Magno Quites Machado Filho" <tuliom at linux dot vnet dot ibm dot com>]

Carlos Eduardo Seo <cseo@linux.vnet.ibm.com> writes:

> Added a check to detect the CPU value in preconfigure, so that glibc is built
> with the correct --with-cpu value. This is only done for Power servers.
>
> 2015-11-15  Carlos Eduardo Seo  <cseo@linux.vnet.ibm.com>
>
> 	* sysdeps/powerpc/preconfigure: Added a check to identify the CPU value
> 	and set it for the --with-cpu configure parameter.
> ---
>  sysdeps/powerpc/preconfigure | 51 ++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 51 insertions(+)
>
> diff --git a/sysdeps/powerpc/preconfigure b/sysdeps/powerpc/preconfigure
> index 0c6fdde..ada7b0c 100644
> --- a/sysdeps/powerpc/preconfigure
> +++ b/sysdeps/powerpc/preconfigure
> @@ -15,3 +15,54 @@ powerpc*)
>    rm -f conftest.i
>    ;;
>  esac
> +
> +# Lets ask the compiler which Power processor we've got.

Trailing whitespace here ----------------------------------^

> +# Note if you add patterns here you must ensure that an appropriate directory
> +# exists in sysdeps/powerpc
> +archcpu=`$CC $CFLAGS $CPPFLAGS -E -dM -xc /dev/null |
> +	 sed -n 's/^#define \(_ARCH_PWR[0-9].*\) .*$/\1/p' |
> +	 sort -r | head -n 1`
> +
> +# Set --with-cpu as appropriate.
> +case "$archcpu" in
> +_ARCH_PWR8)
> +  submachine="power8"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR7)
> +  submachine="power7"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR6X)
> +  submachine="power6x"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR6)
> +  submachine="power6"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR5X)
> +  submachine="power5+"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR5)
> +  submachine="power5"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +_ARCH_PWR4)
> +  submachine="power4"
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU identified as $submachine" >&5
> +$as_echo "$as_me:  CPU identified as $submachine" >&6;}
> +  ;;
> +*)
> +  submachine=""
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: CPU not identified; using default" >&5
> +$as_echo "$as_me:  CPU not identified; using default" >&6;}
> +  ;;
> +esac

You have to check if the user passed --with-cpu before doing this.
If you don't do that you'll overwrite the value passed by the user.

-- 
Tulio Magno