On 01/10/2012 02:13 PM, Peter Rosin wrote:
> Stefano Lattarini skrev 2012-01-10 13:44:
>> On 01/10/2012 12:35 PM, Peter Rosin wrote:
>>>
>>> One further data point; changing that "( sleep 1 ) &" thing followed by a
>>> wait just before AC_OUTPUT into an inlined sleep also fixes the test case.
>>>
>> Thanks for tracking this down. So the question now becomes: why doesn't
>> the trick with background processes work on MSYS? Does maybe MSYS lack
>> proper emulation of POSIX-ish PIDs? If that is the case, can we easily
>> work around that in our situation?
>
> No no, that's not the problem. In this case "make distcheck" runs
> configure, but configure fails so it never reaches AC_OUTPUT and
> the wait call never happens.
>
Ah, good catch. So the problem is not limited to MinGW, but could potentially
hit also when we are building on (say) NFS mounts, right?
> So, the ( sleep 1 ) subshell lives on
> and "locks" the directory (but something else is also going on,
> because changing the subshell to do ( cd /; sleep 1 ) doesn't help).
>
> *pling* new mail, from Eric.
>
> He explains the issue with different words and suggests:
>
> "As for what somewhere/safe should be, $(abs_builddir) is probably
> reasonable."
>
> So, testing that too, but neither cd /, nor cd "$(abs_builddir)" make
> the test pass. Crap.
>
It would probably be worthwhile to try to understand why this is the case.
As a wild guess, would this work?
- ( sleep 1 ) &
+ sh -c "cd '$abs_builddir'; sleep 1" &
> We could fix it in the testsuite only, by adding a trap to configure
> that does the wait if it didn't happen before, but that would make
> use of internals that would perhaps spread. Yuck again.
>
Or we could enhance your original workaround like this:
am__remove_distdir = \
{ test ! -d "$(distdir)" \
|| { find "$(distdir)" -type d ! -perm -200 -exec chmod u+w {} ';' \
- && rm -fr "$(distdir)"; }; }
+ && if rm -fr "$(distdir)"; then :; else \
+## On MSYS (1.0.17) it is not possible to remove a directory that is
+## in use; so, if the first rm fails, we sleep some seconds and retry,
+## to give pending processes some time to exit and "release" the
+## directory before we removed. See automake bug#10470.
+ sleep 5 && rm -fr "$(distdir)"; fi; }; }
am__post_remove_distdir = $(am__remove_distdir)
endif %?TOPDIR_P%
Thanks,
Stefano
