[isabelle-dev] Broken component: jdk7u40

[Makarius]

On Tue, 17 Sep 2013, Lars Hupel wrote:

> I was trying to update to the repository version today, but:
>
> $ bin/isabelle components -a
> ### Missing Isabelle component: "/home/lars/.isabelle/contrib/jdk-7u40"
> Getting "http://isabelle.in.tum.de/components/jdk-7u40.tar.gz"
> Unpacking "/home/lars/.isabelle/contrib/jdk-7u40.tar.gz"
> tar: Skipping to next header
> tar: A lone zero block at 840553
> tar: Exiting with failure status due to previous errors

We've had such incidents before with these huge jdk components.  I had 
informed the local administrators about it, but they did not have any idea 
what could be wrong with the http server -- they made a reboot but it did 
not change substantially.  If anyone wants to investigate further -- 
welcome.  There is no particular need for me to figure out web server 
problems at TUM.

Just for the sake of scientific honesty, there is also some small chance 
that the perl-based download script of "isabelle components" is 
susceptible to bad versions of perl, wrong C libraries, fragile linux 
distributions, whatever.

Generally, one needs to recall that being hooked on the Isabelle involves 
extra work to sort things out manually -- this is not as smooth and 
polished as official releases.  Here that may mean a manual download of 
.tar.gz files, e.g. scp from TUM (although that is not available to 
general public).


 	Makarius