Re: [bug-gettext] [PATCH] gettext-runtime: use @SHELL@ for the SHELL variable definition

[Stefano Lattarini]

Hi Daiki.  One little clarification about Libtool ...

On 05/30/2013 12:31 AM, Daiki Ueno wrote:
> Hi,
> 
> Thomas Petazzoni <address@hidden> writes:
> 
>> you run on a system where sh is a POSIX shell that doesn't understand
>> the += bashim that libtool is using.
> 
> Perhaps it might be fixed with a portability check in the latest
> libtool.
>
No: configure-time code generated by the libtool-provided m4 macros checks
that '+=' is supported by the shell before going ahead and using it.
Otherwise, it reverts to using the inferior-but-more-portable idiom
"var=${var}APP" in lieu of the bashism "var+=APP".  I don't remember the
exact details, but that's the gist of it.

Of course, if you swap the shell under libtool's feet between the
configuration and built steps, the results of that check can become
inconsistent, and you can expect weird problems.

>  Regardless of that,
> 
>>> But due to the
>>> complexity of autotools I was worried it might break something else.
>>
>> All other Makefile.in are doing this, and the SHELL variable gets
>> properly expanded to the correct value, from my testing. So it should
>> be alright.
> 
> Using @SHELL@ here seems to be the right thing, as suggested in the
> Autoconf manual:
> <http://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/html_node/The-Make-Macro-SHELL.html#The-Make-Macro-SHELL>
> 
> So I've pushed the patch.  Thanks.
> 
> Regards,

Regards,
  Stefano