Re: automake 1.12 and AM_PROG_AR

[Simon Josefsson]

Nick Bowler <address@hidden> writes:

>> --- libidn-1.24.orig/configure.ac
>> +++ libidn-1.24/configure.ac
>> @@ -34,6 +34,10 @@ AC_SUBST(LT_CURRENT, 17)
>>  AC_SUBST(LT_REVISION, 7)
>>  AC_SUBST(LT_AGE, 6)
>>  
>> +# automake 1.12 seems to require this, but automake 1.11 doesn't recognize 
>> it
>> +m4_pattern_allow([AM_PROG_AR])
>> +AM_PROG_AR
>> +
>>  AC_PROG_CC
>>  gl_EARLY
>>  lgl_EARLY
>
> First off, this patch seems wrong at a first glance by its use of
> m4_pattern_allow: this is saying that "It's ok for AM_PROG_AR to appear
> verbatim in the configure script".  This suggests to me that the patch
> didn't actually get tested (well) on Automake 1.11, since there will
> almost certainly be an error about AM_PROG_AR at configure time.
>
> This one should actually work properly on both old and new Automake
> (untested):
>
>   m4_ifdef([AM_PROG_AR], [AM_PROG_AR])

Hi.  Thanks for analysis.  Just FYI, I have tested the initial patch on
1.11 and I don't get any errors that I didn't get before.  I assume the
person who reported it tested it with 1.12.

> That being said, the new warning is enabled by the -Wextra-portability
> option that was added to Automake-1.12.  I'm by no means an export on
> this issue, but I think it relates to new support for building with the
> Microsoft compiler: in other words, I think that ignoring this warning
> will not cause regressions in your package but, instead, your package
> will simply not be able to make use of the new feature.
>
> Regardless, I believe that for most packages the new warning is actually
> caused by Libtool, and therefore the correct place to add the call to
> AM_PROG_AR is in libtool itself, rather than ad-hoc patching of each
> package individually.  You can silence the warnings (but not fix them)
> by adding -Wno-extra-portability to AM_INIT_AUTOMAKE.

Is any libtool people reading this, or should I forward this as a
libtool request?

Thanks,
/Simon