Re: What is it with the dependency on config.status

[Stefano Lattarini]

Hi Nick.  Thanks for chiming in, and for the detailed reply!

On 01/09/2012 05:35 PM, Nick Bowler wrote:
> Hello Jan,
>
> On 2012-01-09 17:23 +0100, Jan Engelhardt wrote:
>> On Sunday 2012-01-01 10:24, Stefano Lattarini wrote:
>>> On 12/31/2011 12:29 AM, Jan Engelhardt wrote:
>>>>
>>>> I have seen user-induced lines in Makefile.am like these in a handful 
>>>> of packages:
> [...]
>> For example libntlm [http://www.nongnu.org/libntlm/releases/] in 
>> gl/Makefile.am:
>>
>>      else
>>      byteswap.h: $(top_builddir)/config.status
>>              rm -f $@
>>      endif
> 
> This instance (presumably) comes from Gnulib's byteswap module.  This
> header is generated at make time based on stuff determined by configure:
> so it needs to be regenerated if the package configuration changes.  Or,
> as in the part you quoted, it may need to be deleted if the configuration
> changes such that the header is no longer necessary.  Since config.status
> is updated whenever configure is run, this dependency ensures that the
> headers will be updated if the configuration is changed.  This approach
> is used throughout Gnulib.
>
I believe I remember a discussion on the gnulib list about this "trick",
several months ago ...  Ah-ah, found it:

 <http://comments.gmane.org/gmane.comp.lib.gnulib.bugs/25820>

HTH,
  Stefano