Hello, I tracked down the source of information to this: https://wiki.ubuntu.com/SecurityTeam/PIE
I changed the flags from "-Wl,-Ur" to "-Wl,-U -r", so you wont get an explanation from me, why -U has to be passed for the linker. And by the way, gcc accepts -U aswell, so this might be preferable to be used directly too. I don`t know why those flags aren' t documented, bug in gcc documentation? As far as I understand is that gcc is smart enough to correctly deal with the flags gcc directly received, but the linker lacks that information. I don' t know what the issue is with the C++ Constructors, in the context of this change? (I heard about the issues if those reside in a shared library, use function from libcobald and don't depend on libcobald. Which is more of a broken build to me if you don't add the depended libs, and will bite you the same way if you use GCCs constructor attribute) Kind regards, Norbert. 2017-10-12 10:33 GMT+02:00 Henning Schild <[email protected]>: > Hey Norbert, > > thanks for looking into that again! Could you please explain how and > why that works, or point out what to look at in flint? Mailing list > thread, commit, something like that. > > As far as i can see gcc now gets a "-r" which i do not find in the > manpage. And ld gets a "-U" which i do not find in its manpage. And > there is something about c++ constructors which might change the > behaviour of xenomai. > > Henning > > Am Tue, 10 Oct 2017 16:38:50 +0200 > schrieb Norbert Lange <[email protected]>: > >> Some highly trivial fix attached! >> Its strange that this flag is not documented in the manual (I found >> out abaout this fix from https://launchpad.net/ubuntu/+source/flint) >> >> Norbert Lange >> >> 2017-08-10 11:49 GMT+02:00 Henning Schild >> <[email protected]>: >> > Hi Norbert, >> > >> > Thanks! In fact that issue has come up before and a similar >> > workaround was described. It should be fixed, patches welcome! >> > >> > Henning >> > >> > Am Wed, 9 Aug 2017 16:21:02 +0200 >> > schrieb Norbert Lange <[email protected]>: >> > >> >> Hello, >> >> >> >> Building the xenomai package won`t work because debian now >> >> defaults to using pie, and the linker will complain with "ld: -r >> >> and -pie may not be used together" >> >> >> >> A workaround for now is to add the flags manually: >> >> ../xenomai-3.0.5/configure LDFLAGS=-no-pie CFLAGS="-fno-PIE >> >> -fno-pie -no-pie" >> >> >> >> A real fix would be similar to >> >> http://lists.gnu.org/archive/html/bug-grub/2016-11/msg00011.html >> >> (no-pie is not supported on old and other compilers) >> >> >> >> Kind regards, >> >> Norbert >> >> >> >> _______________________________________________ >> >> Xenomai mailing list >> >> [email protected] >> >> https://xenomai.org/mailman/listinfo/xenomai >> > > _______________________________________________ Xenomai mailing list [email protected] https://xenomai.org/mailman/listinfo/xenomai
