Re: [PATCH 1/8] Add --with-system-zlib in bfd

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Tue, Mar 31, 2015 at 4:46 AM, Pedro Alves <palves@redhat.com> wrote:
> On 03/31/2015 12:33 PM, H.J. Lu wrote:
>> On Tue, Mar 31, 2015 at 3:53 AM, Pedro Alves <palves@redhat.com> wrote:
>>> On 03/31/2015 11:46 AM, H.J. Lu wrote:
>
>>>> It is better for Makefile.am to use what configure.ac defines
>>>
>>> That's orthogonal.  How configure.ac defines what Makefile.am
>>> consumes is the issue.  That can either be through a shared macro,
>>> which makes sure all tools have the exact same command line option
>>> (like AM_ZLIB), or you manually put the same configure.ac bits
>>> everywhere.
>>
>> They aren't the same.  Some tools like ld, which use zlib implicitly
>> via libfd and libtool, don't need to reference zlib.
>
> Sure, that one just drops AM_ZLIB.
>
>> Some only need
>> to reference zlib library.  Some only need to reference header.
>>
>
> And?  If you replace AM_ZLIB's body with:
>
> # Use the system's zlib library.
> zlibdir=-L../zlib
> zlibinc="-I\$(srcdir)/../zlib"
> AC_ARG_WITH(system-zlib,
> [AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> zlibdir=
> zlibinc=
> )
> AC_SUBST(zlibdir)
> AC_SUBST(zlibinc)
>
> then it'll work for those too.  They just won't use zlibinc
> or zlibinc if they don't need it.  Currently you have:
>
> bfd:
>
>> +# Use the system's zlib library.
>> +zlibdir=-L../zlib
>> +zlibinc="-I\$(srcdir)/../zlib"
>> +AC_ARG_WITH(system-zlib,
>> +[AS_HELP_STRING([--with-system-zlib], [use installed libz])],
>> +zlibdir=
>> +zlibinc=
>> +)
>> +AC_SUBST(zlibdir)
>> +AC_SUBST(zlibinc)
>
> gold:
>
> +# Use the system's zlib library.
> +zlibdir=-L../zlib
> +zlibinc="-I\$(srcdir)/../zlib"
> +AC_ARG_WITH(system-zlib,
> +[AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> +zlibdir=
> +zlibinc=
> +)
> +AC_SUBST(zlibdir)
> +AC_SUBST(zlibinc)
>
> gas:
>
> +# Use the system's zlib library.
> +zlibinc="-I\$(srcdir)/../zlib"
> +AC_ARG_WITH(system-zlib,
> +[AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> +zlibinc=
> +)
> +AC_SUBST(zlibinc)
>
> binutils:
>
> +# Use the system's zlib library.
> +zlibdir=-L../zlib
> +zlibinc="-I\$(srcdir)/../zlib"
> +AC_ARG_WITH(system-zlib,
> +[AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> +zlibdir=
> +zlibinc=
> +)
> +AC_SUBST(zlibdir)
> +AC_SUBST(zlibinc)
>
> gdb:
>
> +# Use the system's zlib library.
> +zlibdir=-L../zlib
> +AC_ARG_WITH(system-zlib,
> +[AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> +zlibdir=
> +)
> +AC_SUBST(zlibdir)
>
> and gcc has:
>
> # Use the system's zlib library.
> zlibdir=-L../zlib
> zlibinc="-I\$(srcdir)/../zlib"
> AC_ARG_WITH(system-zlib,
> [AS_HELP_STRING([--with-system-zlib], [use installed libz])],
> zlibdir=
> zlibinc=
> )
> AC_SUBST(zlibdir)
> AC_SUBST(zlibinc)
>
>
>
> They're all the same.  Just a couple doesn't define zlibdir or zlibinc.

If zlib.m4 is changed, I will use it and GCC can also use it. But I
don't know if other packages use zlib.m4.

-- 
H.J.