> 23 mars 2018 kl. 15:45 skrev Alan Bateman <alan.bate...@oracle.com>:
>
>> On 23/03/2018 13:56, Magnus Ihse Bursie wrote:
>> With modern compilers, we can use compiler directives (such as
>> _attribute__((visibility("default"))), or __declspec(dllexport)) to control
>> symbol visibility, directly in the source code. This has historically not
>> been present on all compilers, so we had to resort to using mapfiles (also
>> known as linker scripts).
>>
>> This is no longer the case. Now all compilers we use support symbol
>> visibility directives, in one form or another. We should start using this.
>> Since this has been the only way to control symbol visibility on Windows,
>> for most of the shared code, we already have proper JNIEXPORT decorations in
>> place.
>>
>> If we fix the remaining platform-specific files to have proper JNIEXPORT
>> tagging, then we can finally get rid of mapfiles.
> This seems like a great cleanup as the mapfile have always been a pain to
> maintain. Also shines a light on some technical debt too.
Very much so, yes. I've found a lot of dubious exports, everything from global
variables (yuck!) to functions that does not seem to be used anymore, to lots
of strange exports.
> handleSocketError in libnio is a surprise, this should not be exported and
> should not have been in the map file. I suspect the issue is that jdk.sctp
> is missing a function prototype from its header file (it has its own
> handleSocketError in SctpNet.c).
That might be so, yes.
> NET_Wait in libnet is another one, I can't tell why this was listed in the
> map file.
Neither can I. :-) Once again, my goal with this patch was to keep the produced
binaries as similar to before with the mapfiles. I'll be happy to file
follow-up bugs listing all suspicious symbol handling I've encountered, but I'd
rather not change anything about that in this patch.
> I'm also surprised with java.dll exporting handleRead, winHandleRead, and
> handleLSeek. I didn't see them mentioned in your mail so I'm curious what
> might be using those.
They were previously exported using -export: on the command line for the
Microsoft linker. This was the case for a couple other libraries as well. Yeah,
I forgot to write about that, sorry. :( Been a lot to keep track of, and it
went away when I cleaned up my notes.
Can I consider this a review?
/Magnus
>
> -Alan
