Re: [PATCH] PowerPC: define _CALL_ELF if compiler does not define it

[Adhemerval Zanella <azanella at linux dot vnet dot ibm dot com>]

Ping.

On 27-03-2014 15:47, Adhemerval Zanella wrote:
> On 21-03-2014 17:10, Roland McGrath wrote:
>> It seems questionable to modify CFLAGS for this.  It probably belongs in
>> CPPFLAGS, to begin with.  But I'm not sure I like it modifying the user's
>> CPPFLAGS either.  It might be best to add a new config.make variable for
>> configure-deduced (as opposed to user-specified) CPPFLAGS and accumulate
>> into that.  It would be an analogue to config-extra-cflags
>> (libc_extra_cflags in configure).  While you're at it, generalize
>> libc_extra_cflags so it accumulates and could be used by sysdeps configure
>> fragments, rather than just being single-purpose as it is today.
>>
> Something like this:
>
> This patch make the configure adds -D_CALL_ELF=1 when compiler does
> not define _CALL_ELF (versions before powerpc64le support).  It cleans
> up compiler warnings on old compiler where _CALL_ELF is not defined
> on powerpc64(be) builds.
>
> It does by add a new config.make variable for configure-deduced
> CPPFLAGS and accumulate into that (confix-extra-cppflags).  It also
> generalizes libc_extra_cflags so it accumulates in sysdeps configure
> fragmenets.
>
> --
>
> 	* Makeconfig (CPPFLAGS): Add config-extra-cppflags t list.
> 	* config.make.in (config-extra-cppflags): Set it from
> 	libc_extra_cppflags.
> 	* configure.ac (libc_extra_cflags): Make it accumulate over
> 	configure fragments.
> 	(libc_extra_cppflags): New flag.
> 	* configure. Regenerate.
> 	* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
> 	(libc_cv_ppc64_def_call_elf): Define it to yes if compiler does not set
> 	_CALL_ELF and add -D_CALL_ELF=1 to libc_extra_cppflags.
> 	* sysdeps/unix/sysv/linux/powerpc/powerpc64/configure: Regenerate.
>
> ---
>
> diff --git a/Makeconfig b/Makeconfig
> index 3338ab6..f965398 100644
> --- a/Makeconfig
> +++ b/Makeconfig
> @@ -792,7 +792,8 @@ libio-include = -I$(..)libio
>  # Note that we can't use -std=* in CPPFLAGS, because it overrides
>  # the implicit -lang-asm and breaks cpp behavior for .S files--notably
>  # it causes cpp to stop predefining __ASSEMBLER__.
> -CPPFLAGS = $(CPPUNDEFS) $(CPPFLAGS-config) $($(subdir)-CPPFLAGS) \
> +CPPFLAGS = $(config-extra-cppflags) $(CPPUNDEFS) $(CPPFLAGS-config) \
> +	   $($(subdir)-CPPFLAGS) \
>  	   $(+includes) $(defines) \
>  	   -include $(..)include/libc-symbols.h $(sysdep-CPPFLAGS) \
>  	   $(CPPFLAGS-$(suffix $@)) \
> diff --git a/config.make.in b/config.make.in
> index 416fb9e..132d179 100644
> --- a/config.make.in
> +++ b/config.make.in
> @@ -37,6 +37,7 @@ cflags-cpu = @libc_cv_cc_submachine@
>  asflags-cpu = @libc_cv_cc_submachine@
>
>  config-extra-cflags = @libc_extra_cflags@
> +config-extra-cppflags = @libc_extra_cppflags@
>  config-cflags-nofma = @libc_cv_cc_nofma@
>
>  defines = @DEFINES@
> diff --git a/configure b/configure
> index d4b5edb..ee139bb 100755
> --- a/configure
> +++ b/configure
> @@ -591,6 +591,7 @@ libc_cv_slibdir
>  old_glibc_headers
>  use_nscd
>  libc_cv_gcc_unwind_find_fde
> +libc_extra_cppflags
>  libc_extra_cflags
>  CPPUNDEFS
>  sizeof_long_double
> @@ -7199,9 +7200,9 @@ fi
>  $as_echo "$libc_cv_predef_stack_protector" >&6; }
>  libc_extra_cflags=
>  if test $libc_cv_predef_stack_protector = yes; then
> -  libc_extra_cflags=-fno-stack-protector
> +  libc_extra_cflags+=-fno-stack-protector
>  fi
> -
> +libc_extra_cppflags=
>
>  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the linker provides __ehdr_start" >&5
>  $as_echo_n "checking whether the linker provides __ehdr_start... " >&6; }
> @@ -7266,6 +7267,9 @@ $as_echo "running configure fragment for $dir" >&6; }
>    fi
>  done
>
> +
> +
> +
>  if test x$libc_cv_gcc_unwind_find_fde = xyes; then
>    $as_echo "#define EXPORT_UNWIND_FIND_FDE 1" >>confdefs.h
>
> diff --git a/configure.ac b/configure.ac
> index 43bd8a5..46b37b5 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -2042,9 +2042,9 @@ esac],
>  ])
>  libc_extra_cflags=
>  if test $libc_cv_predef_stack_protector = yes; then
> -  libc_extra_cflags=-fno-stack-protector
> +  libc_extra_cflags+=-fno-stack-protector
>  fi
> -AC_SUBST(libc_extra_cflags)
> +libc_extra_cppflags=
>
>  AC_CACHE_CHECK([whether the linker provides __ehdr_start],
>  	       libc_cv_ehdr_start, [
> @@ -2091,6 +2091,9 @@ for dir in $sysnames; do
>    fi
>  done
>
> +AC_SUBST(libc_extra_cflags)
> +AC_SUBST(libc_extra_cppflags)
> +
>  if test x$libc_cv_gcc_unwind_find_fde = xyes; then
>    AC_DEFINE(EXPORT_UNWIND_FIND_FDE)
>  fi
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure b/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure
> index fbb6334..7f4a7c4 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure
> @@ -163,4 +163,31 @@ default-abi = 64-v2"
>  else
>    config_vars="$config_vars
>  default-abi = 64-v1"
> +  # Compiler that do not support ELFv2 ABI does not define _CALL_ELF
> +  { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether the compiler defines _CALL_ELF" >&5
> +$as_echo_n "checking whether the compiler defines _CALL_ELF... " >&6; }
> +if ${libc_cv_ppc64_def_call_elf+:} false; then :
> +  $as_echo_n "(cached) " >&6
> +else
> +  cat confdefs.h - <<_ACEOF >conftest.$ac_ext
> +/* end confdefs.h.  */
> +#ifdef _CALL_ELF
> +                         yes
> +                       #endif
> +
> +_ACEOF
> +if (eval "$ac_cpp conftest.$ac_ext") 2>&5 |
> +  $EGREP "yes" >/dev/null 2>&1; then :
> +  libc_cv_ppc64_def_call_elf=yes
> +else
> +  libc_cv_ppc64_def_call_elf=no
> +fi
> +rm -f conftest*
> +
> +fi
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_ppc64_def_call_elf" >&5
> +$as_echo "$libc_cv_ppc64_def_call_elf" >&6; }
> +  if test $libc_cv_ppc64_def_call_elf = no; then
> +    libc_extra_cppflags+=" -D_CALL_ELF=1"
> +  fi
>  fi
> diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac b/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
> index c9cd4bc..5733f79 100644
> --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
> +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/configure.ac
> @@ -12,4 +12,14 @@ if test $libc_cv_ppc64_elfv2_abi = yes; then
>    LIBC_CONFIG_VAR([default-abi], [64-v2])
>  else
>    LIBC_CONFIG_VAR([default-abi], [64-v1])
> +  # Compiler that do not support ELFv2 ABI does not define _CALL_ELF
> +  AC_CACHE_CHECK([whether the compiler defines _CALL_ELF],
> +    [libc_cv_ppc64_def_call_elf],
> +    [AC_EGREP_CPP(yes,[#ifdef _CALL_ELF
> +                         yes
> +                       #endif
> +    ], libc_cv_ppc64_def_call_elf=yes, libc_cv_ppc64_def_call_elf=no)])
> +  if test $libc_cv_ppc64_def_call_elf = no; then
> +    libc_extra_cppflags+=" -D_CALL_ELF=1"
> +  fi
>  fi
>