RFR: 8217450: Add PackageEntry::locked_lookup_only

[Lois Foltan]

On 1/22/2019 10:21 AM, Claes Redestad wrote:
>
>
> On 2019-01-22 16:11, Aleksey Shipilev wrote:
>> Mmm. Compilers might complain we do not use the returned value? I 
>> think the previous way made a bit
>> more sense, and was a bit faster. Just move the local variable 
>> declaration?
>
> Ok - updated http://cr.openjdk.java.net/~redestad/8217450/open.01/ in
> place and running some sanity tests before push.
>
> Thanks!
>
> /Claes

Hi Claes,

The code change in modules.cpp lines #211-214 does not look correct.  
PackageEntry::locked_create_entry_or_null() will return NULL if the 
package exists and has already been created.  The code at lines #211-214 
need a PackageEntry to be successfully returned for java.base packages 
created during bootstrapping so we can decrement the refcount for it 
appropriately.

Thanks,
Lois