RFR(xs): 8171408: [aix] TOC overflow when linking the gtest libjvm.so
thomas.stuefe at gmail.com
Tue Dec 20 08:30:00 UTC 2016
Only change is that I removed the offending filter-out expression. This
means that gtest modules are compiled with both -qpic followed by
-qpic=large, but the latter should take precedence, so it is ok. Also keeps
the makefile simple.
Kind Regards, Thomas
On Tue, Dec 20, 2016 at 9:21 AM, Thomas Stüfe <thomas.stuefe at gmail.com>
> Hi Erik,
> On Tue, Dec 20, 2016 at 9:17 AM, Erik Joelsson <erik.joelsson at oracle.com>
>> I understand why you want to filter out the -qpic flag from the general
>> JVM_CFLAGS, but that kind of logic is brittle so we try to avoid it unless
>> absolutely necessary. I prefer to just rely on the tools treating command
>> line options as the last one takes precedence. I assume the AIX compiler
>> behaves that way too and that a -qpic=large will override a -qpic earlier
>> on the command line. We have consciously designed SetupNativeCompilation to
>> add all the *FLAGS in the order of most specific flags last for this reason.
> You are right, and Volker just complained about the same thing :) I'll
> post an updated ref where I just rely on qpic=large following qpic. I was
> not happy with that filter-out expression either.
>> So, could you try removing the filtering and see if it still works?
>> On 2016-12-18 13:50, Thomas Stüfe wrote:
>>> Hi all,
>>> please take a look at this small fix. In short, on AIX when linking the
>>> gtest version of libjvm.so, the TOC overflows.
>>> So the gtest libjvm.so must be linked with -bbigtoc, in contrast to the
>>> regular libjvm.so, which has no problems and can keep using a small TOC.
>>> Also, I compile all gtest objects with -qpic=large. Note that this only
>>> affects the gtest objects. The regular objects - which the gtest
>>> shares with the regular libjvm.so - I left at -qpic[=small]. This means
>>> pay a bit of a performance overhead in the gtest libjvm.so but leave the
>>> regular libjvm.so at its optimal linker settings.
>>> (Hope the webrev link works, the webserver is still down).
>>> Kind Regards, Thomas
More information about the build-dev