Re: Problem with make

[David Kastrup]

"address@hidden" <address@hidden> writes:

> hello,
>
> On Wed, Sep 21, 2011 at 05:13:00PM +0100, Phil Holmes wrote:
>> On my fast build system, I can't currently get a successful make.
>> Abort changes, pull, clean build directory.  The build ends with:
> ...
>> As you see, the problem is a missing AUTHORS.texi.  The odd thing is
>> that on previous make runs, I get
>
> yep, happens about 10% of the time for me.  Running "make" again
> fixes it.  (almost always -- the chance of two failing runs is
> about 1%.  That's happened twice to me that I can recall)
> - - - 
>
> happens to me nearly every time i make. You get news.tely and
> authors.texi. Failing. Run make again and it's fine. Never had two on
> the trot like graham.
>
> I probably run make about 10 times a day at the moment, checking
> patches. I'm used to it and just assumed it was one of our build
> quirks. You'll see lots more on faster machines in my own personal
> experience.

That points to either a problem with parallel make processes, or more
likely a time stamp resolution problem.  When file modification dates
are only accessed with second resolution (because the info is not
available in the file system type, or the application does not use it)
and a process for updates is quite fast, an updated dependent file may
seem to have the same time stamp as its original.

-- 
David Kastrup