Hi Kim,
On 30/09/2018 11:23 AM, Kim Barrett wrote:
Please review this change to HotSpot build options and code to
eliminate the suppression of deprecation warnings when building with
clang.
Just as a historical note the no-deprecation-warning was only applied to
os_bsd.cpp in the distant past. No idea when it became global.
There are two code changes:
(1) Replace calls to finite() with C99 isfinite(). This also affects
gcc-based builds, but isfinite has been supported there for a long
time too.
Ok.
(2) Remove call to _dyld_bind_fully_image_containing_address, which
seems to have been deprecated since MacOSX 10.5. Instead use the
recommended replacement "dlopen(RTLD_NOW)". However, it might be we
don't need to do anything here anymore. I ran tier1-5 test without
the dlopen without any problems. But I'm not familiar with the
original problem, so not sure that's convincing. Perhaps another RFE
to determine whether this code can be deleted?
The use of _dyld_bind_fully_image_containing_address, as per the comment
is a workaround to force full binding of symbols in the library. I don't
know where the "callbacks" referred to in the comment come from or why
they may be unaligned - this seems to be day 1 code for the OS X port
from 2008:
http://hg.openjdk.java.net/macosx-port/macosx-port/hotspot/rev/be94a5de4d32#l75.4001
I've cc'd the macosx-port-dev mailing list in case someone still
subscribed there might know the answer.
If you don't have unaligned symbols then the workaround is not needed.
In that case the replacement dlopen is also not needed (and it isn't
needed to actually dlopen anything as you are opening the current
library!). So it is not surprising that removing the dlopen causes no
problem.
With the dlopen in place however the code looks very strange and there's
no guarantee it actually engages the workaround of the original function.
So I'd say this either has to be removed completely or else left alone.
Thanks,
David
CR:
https://bugs.openjdk.java.net/browse/JDK-8211296
Webrev:
http://cr.openjdk.java.net/~kbarrett/8211296/open.00/
Testing:
Mach5 tier1, tier1-5 on MacOSX.
