On 2014-01-29 10:03, David Holmes wrote:
Hi Magnus,
I don't object to ccache being off by default but I would like the
--disable-ccache flag to remain otherwise I will have to edit a bunch
of build scripts and will need different versions for 9 vs 8. So
please maintain backward compatibility here.
Aside: it would make most sense to me for there to be both --enable-x
and --disable-x flags regardless of what the default might be.
That is actually the case already. AC_ARG_ENABLE adds both the
--enable-x and --disable-x as valid configure arguments so
--disable-ccache will still be accepted (and have no effect).
/Erik
Thanks,
David
On 29/01/2014 9:31 AM, Magnus Ihse Bursie wrote:
Bug: https://bugs.openjdk.java.net/browse/JDK-8027584
While ccache can be used to speed up recompilations, there are also
several issues with ccache. Old versions does not work correctly for the
jdk (we try to detect that). It does not work well on other platforms
than Linux; on Windows it does not work at all. Nevertheless is ccache
enabled on Windows if it is installed, which it apparently tends to be
with Cygwin nowadays, requiring the use of --disable-ccache to avoid
compilation failure.
In many circumstances ccache also does not provide any performance
benefit. For instance, new compilations gets a performance hit. Only
recompilations benefits.
It is better to turn this upside down. This patch makes ccache disabled
by default, on all platforms. If you want ccache and are sure you are in
a situation that benefits from it, then you can enable it. It also
removes the output in configure hinting that ccache should be used.
WebRev:
http://cr.openjdk.java.net/~ihse/JDK-8027584-disable-ccache-by-default/webrev.01
/Magnus
