configure - gcc >4.6 needed for JDK9 build

[Kim Barrett]

> On Jan 24, 2017, at 7:34 PM, David Holmes <david.holmes at oracle.com> wrote:
> 
> Hi Kim,
> 
> On 25/01/2017 7:25 AM, Kim Barrett wrote:
>>> On Jan 23, 2017, at 5:34 AM, Mike Burton <mikeb at mycosystems.co.uk> wrote:
>>> 
>>> Hello,
>>> 
>>> I ran an OpenJDK Hack Day session on Saturday, at which some people got stuck on lost a fair bit of time, failing to build JDK9. Then we found that updating gcc from 4.6 to 4.8 fixed it.
>>> Could the `configure` script be updated (by running get-source.sh) so as to check for minimum required gcc version?
>>> 
>>> Best Regards
>>> 
>>> Mike Burton
>> 
>> I don’t think there is supposed to be a requirement for gcc > 4.6 in JDK 9.  I’m pretty
>> sure there are folks still building with older versions.  It would be helpful to know the
>> details of the platform and the error messages that led to the conclusion that something
>> more recent was required.
> 
> We may have "accidentally" moved on to gcc 4.8+. Even the ppc builds, which are still listed as using 4.1.2 on the wiki:
> 
> https://wiki.openjdk.java.net/display/Build/Supported+Build+Platforms
> 
> are now using 4.8.5:
> 
> http://cr.openjdk.java.net/~simonis/ppc-aix-port/ (look at a build log)
> 
> So some breakage with earlier versions may have crept in. I thought I recalled a few issues but can't see any bug reports.

The PPC build from SAP was the one I was thinking of as still being around.
And it does seem they’ve moved on too, which is useful to know.
So yes, entirely possible something crept in if there isn’t frequent testing.