Heads Up: JDK 7 Linux platforms moving to Fedora 9

[Andrew Haley]

Martin Buchholz wrote:
> On Fri, Dec 19, 2008 at 03:39, Andrew Haley <aph at redhat.com> wrote:
>> Does this failure to run on Ubuntu dapper have anything to do with
>> Fedora 9?
> 
> Since it appears to have been caused by building on Fedora 9,
> the answer is very likely "yes".
> 
> In particular, Fedora 9 very likely has a glibc version > 2.3,
> and apps built on such a system tend to have linker
> dependencies on symbols introduced in glibc 2.4,
> causing
> libc.so.6: version `GLIBC_2.4' not found
> load-time errors.
> 
> I also suspect compiler runtime incompatibilities.
> 
> (I've never used Fedora, and I'm not suggesting there's anything
> wrong with Fedora 9, aside from being too new.)

I guess it depends on what the builds are for.  OpenJDK is the future,
and builds of OpenJDK are forward-looking.  Yea, even OpenJDK 6.  At
some point you have to admit that you *need* to build on something
more recent.

As an example of the cost of building on old boxes, OpenJDK contains
prototypes for epoll(7) that are incorrect for some arches.  These
prototypes exist because epoll didn't come into existence before
Kernel 2.6(ish), and OpenJDK was being built on an old box, so the
prototypes were copied from the kernel headers on (I think) an x86
box.  This bug causes bizarre and hard to debug behaviour on non-x86
arches.

At some point you have to get rid of cruft like this.  If not now,
when?

Andrew.