Re: 1.16.90 regression: configure now takes 7 seconds to start

Bruno Haible wrote:
> Jacob Bachmeyer wrote:
>   
>> under what conditions can "checking that 
>> generated files are newer than configure" actually fail?
>>     
>
> I mentioned two such conditions in [1]:
>   - Skewed clocks. (I see this regularly on VMs that have 1 or 2 hours
>     of skew.)
>   - If the configure file was created less than 1 second ago and the
>     file system time resolution is 1 second. (This happens frequently
>     in the Automake test suite.)

In the first of those scenarios, AM_SANITY_CHECK should bail out.  In 
the second case, AM_SANITY_CHECK should delay for 1 second, and then 
find the test file newer than configure.

One (or both?) of us is misunderstanding something here.  First, 
configure performs AM_SANITY_CHECK ("checking that build environment is 
sane") and bails out if that test fails.  For that test to pass, a 
generated file (conftest.file in the old version) must test to be newer 
than configure.  If that test fails, configure aborts and "checking that 
generated files are newer then configure" is never reached.

Given that "checking that generated files are newer than configure" is 
reached, which implies that a file produced before any actual tests were 
run was found to be newer than configure, how can config.status, which 
is produced /after/ tests are run, now fail to be newer than configure?


-- Jacob